Rebuilding SS28 M-11 Engine

SS Engine Removal & Rebuild (12-02)

Removal and rebuilding of the 11hp Universal Model #5411 from a 28’ Sea Sprite.

During the summer I noticed a broken mount on the engine. The flange of the bell housing is where the aft motor mounts connect. The flange on the port side was broken on the outside of the hole. While it seemed to be ok and might run that way for another 20 years, I did not want to take a chance with next year’s sailing season.

Another concern was that the temperature of the engine was climbing up. The average operating temp was about 160-165 degrees. The normal temp should be about 135 – 155 degrees. I thought that I might have a problem with water circulating through the engine.

It was also a good opportunity to go through the whole engine and learn what makes it tick. My engine had a lot of rust and corrosion on it and that always bothered me. A small water leak in places you never see can do a lot of damage. You also have the opportunity to fix problems before they become major ones. It also gives you a much better working knowledge of your engine so if something ever happens, you will be in a better position to trouble shoot it.

Since the engine only weighs 245lbs, it is not a major undertaking to get it out and home to work on it. While it is a pain and some work to do, it will save you the cost of a new engine.

My goal was to:
* Repair the broken flange on the bell housing
* Replace rusted motor mount
* Clean out the cooling system, head, water jacket around the block, manifold
* Replace the thermostat
* Replace the temperature-sending unit
* Replace the oil sensor
* Replace all water hoses and clamps
* Clean and repaint engine
* Have alternator and starter checked and cleaned
* Modify oil drain

While we are at it, I might as well:

* Add fuel sender & fuel gauge
* Build new boards for the sides of the lockers
* Put a light above the engine
* Clean out the bilge of old tools and oil
* Redo the bilge pump
* Paint the lockers

What I also HAD to do:

* Repair the wiring harness
* Replace the water lock and exhaust Hose

How much mechanical knowledge is needed? I consider myself to be pretty good with my hands. I did a lot of grease work when I was younger (had no choice for the clunkers I drove). This cheap Irishman does not pay anybody to do something I can do, or think I can do. I figure that if they can do it, so can I. All’s you need is logic, some tools, sockets and wrenches, a dry place to work on it. It helps if you keep the job moving as you won’t forgot how it goes back together as quickly. Making notes as you go will also make it easier to remember, as will as putting the nuts and bolts into separate envelopes or bags as you go and mark them.

My wife said that the spray paint that I used did have a strong odor to it so it might be a good idea to make sure it is well ventilated as you paint the engine. It took about 3 –4 weeks for me to finish mine, but I was in the middle of many other projects at the time. One to two weeks should be more than enough time to do a good job on the rebuild.

Overall the rebuild was very easy. I left the block in the garage and took the parts into the basement as I took them off. I used envelopes to place all the nuts, bolts, valves, springs, etc. when I removed them from the engine and marked them. I cleaned the grease off the engine with acetone, paper towels, and a toothbrush before repainting. A clean engine doesn’t retain as much moisture.

I used an ice pick and screwdriver to chip away a lot of the corrosion in the head and ports. I took out an amazing amount of corrosion that reduced the flow of water around the engine.

I also replaced all gaskets that I removed. Some of them could be possibly reused, but I did not think it was worth it. With the exceptions noted in each segment, I used permatex or gasket sealer on both sides of the gaskets. Some people say it is not necessary, but I chose to.

With the reduction or complete blockage of some of the water ports in the engine, I now know why the temperature was rising on the engine. Had I not rebuilt her when I did, I would be replacing her next year.

Now, I make NO claims to be a mechanic. These were my observations as I rebuilt my engine. What worked for me might not work for you. Please use your own judgement when working on your engine. Do not hesitate to do it thinking it is beyond your experience. It’s not!!

The Engine

It is a Kobata Block built in 1981.It is a 2 cylinder 11hp diesel engine. It was called the Universal # 5411. Appanoug Harbor Marine of Warwick, RI was a dealer for the Universal Engines. They received the blocks from the factory and they installed everything on the blocks. They than sold them to the boat builders and the general public. All of the engines that were installed in the Sea Sprites 28’ were bought from Appanoug Harbor Marina. There were about _______ of them built.
What came from the factory is metric, but there are some SAE nuts and bolts used.

The transmission is a Hurth transmission. Built in Italy for the Carl Hurth Co, it is made out of cast aluminum. It is extremely lightweight. It has a 2:1 ratio. There are rebuilding kits available, as well as new and rebuilt. A new transmission goes in the range of $1,100.00 I am told. When re-filling your transmission, use type ______ transmission fluid.

In the beginning:

First: Get a copy of the service manual and the parts manual for the Universal 11hp motor model # 5411. It is a Kobota block. They are available, among other places, from Appanoug Harbor Marina (see vendor list). Without this it makes the rebuilt impossible (at least for me).

Second: Take a pad of paper and go over the whole engine and take notes of what goes to what. If you remove it in the fall and go to re-install it in the spring, you will have forgotten where something goes. It might help if you take some pictures.

Engine cradle
Make a cradle for the engine. I made a cradle for the engine as shown below. When you lift the engine off the mounts and slide it into the cabin, you have to have something to rest it on or it will not stand up. This made it SO much easier to deal with. I highly recommend this step. It is worth the time invested.

I made the cradle from a 2×10. I used 3/8” hanger bolts to secure the motor to the cradle. The cut out on the side is for the oil dipstick. Make sure that you make it only as big as necessary otherwise it will not make it out of the companion way.
Able Crew
It took 3 able people to remove the engine from its mounts and get it onto the cradle on the cabin sole. One person in the lockers holding the transmission, another person in the cabin holding the front of the engine and another person on a come-a-long taking the weight off the engine. We used a 4×4 across the companionway to connect the come-a-long to.

I made a derrick to lift the engine out of the cabin and lower it to the ground. This simple devise worked perfectly. If you do not have a travel lift or other method if lifting, I suggest this.
See appendix A

*Standard and Metric socket sets and wrenches. 10mm & 7/16” and up
*Torque wrench
*Gear puller or 2 flat bars
*Old wood chisel for scraping gaskets, chipped paint, spinning nut off pulley
*Wire brush- hand and round wire brush on arbor for drill
*Toothbrush (for cleaning)
* Ice pick- it helped in chipping out the sediment from the head, manifold, etc.
* WD-40
* Allen wrenchs

Disconnecting the Engine

Disconnecting the shaft
There are 4 bolts that connect the shaft flange to the back of the transmission. Unbolt these 4 bolts and slide the shaft aft.

Note: This also might be a good time to replace your cutlass bearing (Appendix B), check the shaft to flange connection, stuffing box packing and hose clamps. Often the hose clamps that hold the stuffing box to the shaft log get corroded and you can’t tell because they corrode on the bottom where you can’t see them. This is a cheap part to replace and might keep the boat from sinking. My hose clamps were so rusted that they broke when I tried to remove them.

Disconnect the exhaust
This was relativity easy because I went through the nightmare earlier this season when I had to replace the injection nipple. Remove the water hose that comes from the thermostat. Disconnect the short exhaust hose that leads from the exhaust manifold to the water trap. Make sure that the exhaust pipe from the manifold does not extend out past the engine width, for that might interfere with the removal of the engine from the compartment. If it does, you might have to disconnect it from the exhaust manifold.
Note: If you have a water heater, then you will have to disconnect the hose from the thermostat to the water heater and from the water heater to the injection nipple.

Disconnect the Water Intake Hose
This might be a good time to replace that old thru-hull and shut off.

Disconnect the fuel lines
Mark the fuel feed and return lines at the tank. Be careful about spilling. Have a container and a few rags with you when you go into the locker. It’s tough to get out and back in very fast…
Note: Remember to mark which is which, supply and return lines.
Electrical Connections (wiring harness)

These were the connections on my engine. Check yours before disconnecting, for they might be different than mine.

Orange wire (about 10 gauge) that goes to bolt on alternator (bolt on top)

Yellow wire off alternator with clip goes to purple wire from harness
(Note: bell wire clips into this and goes to hour meter) Change wire

Yellow w/ red strip to pin on starter

Red wire from harness and red wire from battery both go to bolt on starter
Temperature Sensor
Tan wire from harness goes to bolt on front of engine directly below water cross-over

Oil Pressure Sensor
Light Blue wire with female plug that fits onto the oil sensor located on port side of engine near exhaust flange. I had to remove the female spade plug and replace it with a loop electrical fitting that fastens to a bolt on the sensor

Glow Plugs
Thick Grey wire goes to the aft glow plug and that they have a jumper wire that connect the forward glow plug.

Other from harness

Ground wire goes to top bolt on exhaust flange (ground)

Boat Ground goes to bottom bolt on exhaust flange

Battery Ground
Goes from negative terminal from battery to the top bolt on bell housing.
Fuel system

Fuel return line goes from top of fuel tank to nipple behind aft injector (small 1/8” hose at engine that goes to ¼ “ line that ends at tank

Fuel line to engine goes to water separator on stbd side of engine compartment and than goes to round fuel pump on stbd side if engine.
Engine water lines

Hose out of thermostat goes to aft inlet on hot water heater

Hose out (forward) goes to injection nipple in exhaust line

Engine intake goes to strainer inlet and outlet goes to “T” that goes to water pump and water return from engine

Dismantling of Engine

Removal of Thermostat Housing

There are 2 studs coming out of the manifold that bolts the thermostat housing to the exhaust manifold. Both nuts were rusted so badly that I had to use visegrips to remove the nuts. Once the nuts came off, I removed the studs, and replaced them with new ones, as well as new stainless steel ¼ -20 nuts and lock washers.

Note: When I removed mine, the hole allowing water into the thermostat should be about ½” diameter. Mine was reduced to about 3/16”, allowing less that one half of the water through. There is no way to see this unless you take the thermostat housing off.

Removal of the Exhaust Flange
9/16” nuts on flange. Good Luck!! I had to get a 4 ½” offset grinder with and abrasive wheel to grind 7/8 of the way through the nuts and than use visegrips to get the nuts off. I did it when it was in the boat so it would be 10 times easier in your garage. Replace exhaust flange gasket # 299182-A.

NOTE: I strongly recommend that you remove the insulation around the injection nipple and check it. They have a tendency to weaken because of the design of the water inlet. Mine blew this summer and when I examined it, you could put your finger through the steel pipe. There is no way to check unless you remove the insulation. Take off the insulation on the injection nipple to check it. It may look good so put a pair of pliers on it to check. Now is the time to do it. Believe me!! Also, use Schedule 80 steel pipe. The wall thickness is greater than standard pipe.

Removal of Exhaust Manifold
First, I cut the hose that comes from the cross over from the front cover. There are 4 bolts that hold the exhaust manifold on to the block. Remove the bolts and the manifold came right off. I used an ice pick to chip out a lot of the built up rust and corrosion inside the manifold. (I took out about a hand full of “crap”). Remove the hose clamp and the rest of the hose. I washed it out and repainted it. I also replaced the 2 studs that hold on the Thermostat housing.

Note: The red fitting on top goes to the crossover from the alternator bracket that houses the temperature sensor. The thermostat bolts on to the 2 stud on the dark oval. The opening should be about ½” as shown, but was included down to about ¼”, letting half of the water out to the exhaust. I also had to replace the short studs that hold on the thermostat housing.

Intake Manifold
There are 4 – 6mm bolts that hold on the intake manifold. In order to get to one of the bolts you have to remove the fuel filter assembly. You loosen it with an Allen wrench. Check that the air bleeder bolt on the top if free when you need to bleed it when you re-install and go to start the engine. I cleaned it and put a new coat of paint on it. Replaced the 2 gaskets. I did not use sealer on the gasket.
Removal of the front cover:

The reason to remove the front cover is to check the water seal on the block. I was told that they often fail and if it still is original, it SHOULD be replaced. I was not sure if it had been replaced, so for the price of a couple of gaskets, you don’t want to take a chance. As it turned out, mine had been replaced before. The oil pump is also under this cover. Mine seemed to be working fine, so I let it alone. If you know that your water cover was replaced, there might be no reason to remove the cover.

Note: The oblong plate on the front of the engine is the water cover plate that should be checked if you take the front cover off. When I took mine off, it was fine. I used the opportunity to chip out some rust build up with an ice pick.
Water Pump.
Disconnect the hoses and remove the 2 bolts that connect the water pump to the mounting flange. The water pump slides straight out. There is a 1” shaft extension that will come off. I took it to the wire wheel to clean it up and I painted it. I also refilled the grease in the cap (If you have an Oberdorfer Water pump) It just fits back in the slot when re-installing it. Replace gasket when replacing water pump. I used sealer on gasket when re-installing it, but it probably is not necessary.

Front Pulley
You must remove the pulley from the front of the crankshaft. To do this, bend down the tab keeping the nut from spinning off. I soaked it in WD40 for a day or so to loosen it up. I did not have a metric deep socket that big so I used an old wood chisel and put it at the corner of the nut and tapped it with a hammer counterclockwise. It took just a few taps and the nut came spinning off. I tapped the pulley lightly with a hammer for a minute or so to break up any rust and than I took 2 small flat bars and placed one on each side of the pulley and pressed down. It moved easily and slid off. If you have a gear puller, that would be perfect.

Speed Control
Next, remove the 4 bolts that hold down the speed control lever on stbd side top of the cover. Once the bolts are removed, carefully lift the cover and you will see a spring attached to the bottom of the lever. Remove the spring from the lever. Then look inside and you will see a second, tiny spring connected to the cover. Again, make a note on how the spring is attached and unhook it from the lever in the block.
Important: Make a note of how the springs are attached and remove the spring from the lever. They must be re-attached in the same manner.

Dipstick Tube
In order to get the cover off you will need to remove the dipstick. First, drain oil from the engine. Once that is done, remove the 2- 6mm bolts that hold the dipstick tube to the pan. There is a bolt that holds on the front cover that also holds on the top of the dipstick. Remove the bolt and the tube should come right off. I cleaned and repainted the tube. Replaced the gasket from the tube flange to the oil pan. I used sealer on both sides of the gasket.

Front Cover
Now, loosen, not remove the 14 bolts that hold the cover on. With the bolts still in the holes, slide the cover off. It should come right off. There are 3 o-rings inside that might fall out. This is OK because you will be replacing them anyway.
3 oil seal
Stud for
speed control
Oil relief valve

Note: On the bottom left of the picture you will see the 3 round depressions where the 3 o-rings go. The oil filter screws on just above them on the left side. The hole in the center of the housing is where the crank comes through and you can see the oil seal that should be replaced. The hole on the upper right of the housing is where the shaft for the water pump goes through. Just above and to the right of the water pump you will see a stud the one of the springs for the speed control hook to. You get access through the top speed control cover. Make sure you dis-connect this spring before you take off the cover.
1) Important: When you re-install the cover, you have to put the gasket on the block first and than place the cover onto it. If you place the gasket on the cover and try to place the cover on the block, it will not make it past the gears. I used sealer on both sides of the gasket.
2) Important: There are also different length bolts that are uses to attach the front cover to the block. I suggest that you dry fit the cover with ALL the bolts before you go for the final fit.
3) I used a little sealer on the O-rings to hold them in during re-assembly so they would not fall off.

Oil relief valve:
With the front cover off, Below the oil filter is an oil relief valve. The manual mentioned cleaning this if your engine runs in dirty conditions. I don’t know what they mean by that, but my oil gets dirty so I guess it should be cleaned.

Water Cover Plate:
Once the cover was off, I removed the water cover plate to check it as well as any corrosion inside. There are 2 6mm bolts that hold it down. You need a 10mm wrench to get at them because of the gears. Replace gasket. Again, I used sealer when re-installing the gasket.

Oil seal:
There is an oil seal that should be replaced if you take the front cover off. It is where the crank goes through the cover. Just pull it out with a pair of pliers and insert the new one. Evenly tap down the oil seal till flush with cover.
NOTE: make a note on how you remove the old one and replace the new one in the same direction.

Re-installing the Cover
* The front cover gasket can only go on one way. I used a little sealer on the O-rings to hold them in place while replacing the cover. I also used a little on the complete edge of the gasket. Make sure that you have the right bolts in the right holes.
* Connect the 2 springs on the speed control and re-bolt the cover down.
* Re-Install the water pump
* Re-install the pulley, locking washer and nut
Gaskets needed:
1 _______ Water pump to flange
1 _______ Front cover to block
3 #300160 O-rings
1 _______ Speed control cover gasket
1 ________ Oil seal
1 #299364 Water seal on front of block
1 #301755 Water cover if needed
First, drain oil (should be drained if you removed the front cover first). Remove the bolt on the top of the dipstick and than remove the 2 bolts that hold the dip stick to the pan. Remove gasket and clean surfaces. Than, remove the 14 bolts that holds the oil pan to block. A 10mm socket is used. (I had a couple that were rusted and the socket just spinned. I used needle nose visegrips and they came right out. I had to replace 4 bolts. (They are special bolts with longer heads.) I replaced the gasket and used permatex on both sides of the gasket.

Dipstick Gasket # 299226 Oil Pan gasket #299367

Note: The oil pick-up is here. Everything looked ok so I did not touch it. Also, I did not have to touch the crank, pistons, connecting rods, seals, etc. If you suspect any problem, now is the time to pull that apart.
Oil drain plug
Changing oil was always a pain so I decided to make my life easier. I had the 12mm drain hole tapped to ¼ “ NPT. It was very close to that size so no drilling was needed. The wall thickness of the drain plug opening did not change so I did not weaken it by doing this. Out of the drain hole I threaded in a ¼” brass street 90 and a ¼” ball valve. Out of the ball valve I threaded in a ¼” barbed hose fitting. I fit an 18” piece of 3/8” diameter hose over the fitting and secured it with a hose clamp. All I will need to do to change the oil is to place the hose in a container and open the ball valve. I will place a bolt in the end of the hose to keep it from dripping in between oil changes.
Transmission and Bell Housing
The transmission was built in Italy for Carl Hurth of Germany. My transmission seemed to work fine so all I did was drain and replace the fluid, clean and repaint it. The repair and parts manuals do not cover it so I decided not to be adventurous. My father told me if it isn’t broke, don’t fix it. There are 100’s of web sites on it if you look in at ‘Hurch transmissions’. One site I looked at,, recommends replacing the spring loaded damper plate that mounts between the gear and the flywheel every time the engine is removed. ( I was told that is B.S.)
Note: MER Equipment at has repair/parts manuals for the HBW5 for $32.00 and complete overhaul kits for $191.67


Valve Cover
There are 2 nuts that hold on the valve cover. Remove the 2 nuts and lift the cover straight up. There is a re-usable rubber gasket that forms a seal at the block. Unless it was leaking, I do not think that it needs replacing. There is a screen in the top of the valve cover that you should check once you have it off. Remove the 2 Philips head screws and remove the plate. Inside is a screwing material that prevents anything from getting into the valves. Unless it is clogged, it’s OK. This is straightforward. I cleaned the cover and re-painted it.

Once you have everything off the head, i.e. Manifolds, and the alternator bracket, it’s time to remove the head. First, you must remove the rocker arm assembly so you can get to the center bolt with a socket. Remove the 2 nuts on the studs and the rocker arm assembly will slide right up. Next, remove the push rods from the block. They slide right up. As I took them out I marked them as to which valve they went to. Than, remove the bolts that hold on the head. Tap it lightly with a rubber hammer. The head should come right off. The valves come off with the head. I chose to take apart the rocker arm and remove the valves because I thought they were ok and I was going to just clean it and put them back in. To remove the valves and springs, I placed a 10mm boxed end wrench
over the stud that held the rocker arm and then I placed a socket over the stud. I than replaced the nut on the stud so it would hold down the wrench. I adjusted the nut so the wrench was even with the spring and put the wrench on the edge of the spring and pushed down. (you have to put a block of wood under the valve so that when you push down with the wrench, the whole valve does not move) See Photo _____. Once that the spring is compressed a little, I used an ice pick and a pocket knife to pry out the 2 retaining clips that hold the valve in. The valve slips out the bottom. I placed all the parts in a bag and labeled each one as I took them out. I did this for all 4 valves.
Head STBD side:

The 2 round holes is where the exhaust manifold bolts up to the block. Note the freeze out plugs on the side and top of the head

Head STBD side:

The 2 square holes are where the intake manifolds bolts on. The 2 round holes, one in between the square holes and one to the right of the second square holes are for the 2 glow plugs.
Intake ports
Glow plugs
Once the head was off I used an ice pick to chip out the crud that was built up from the cooling water. I took out handfuls of salt and rust. I than decided to bring the head down to Simplex Machine Shop in Providence, RI (see vendor list). I asked then to check it and check to make sure that the valves were seating properly. WELL, I needed 4 new valves, new valve seats, new valve seals (there were none on it from and earlier repair???). I also had the head surfaced. They also removed the freeze out plugs and cleaned out the stuff I couldn’t get and replaced the freeze out plugs. They told me that the valve guides were OK so they were not replaced. I supplied the valves and seals, they had the seats.

I taped off the head and painted it. Re-assembled the manifolds and replaced the head and torque the head down. Than insert the push rods and re-assemble the rocker arm.
Note: First, let me say, “do as I say and not as I do”. Once you get the head off don’t bother taking the valves out. Just take it down to the machine shop and let them clean it and check it out. They will tell you if you need parts and once you get them, they will put it back together. You do not save or any money by playing with it yourself unless you are a real motor head.
Head resurfaced:

I had the head re-surfaced at a machine shop where they installed new valves, seats and seals. They pressure tested it and cleaned it up.
Re-Installing Head Components
Once the head is done, valve guides, valves seats and valves checked, it’s time to re-assemble the head. I decided to put the head together and than bolt it to the block as one piece, but you can install them after the head is bolted on to the block.

Thermostat Housing
First, I attached the thermostat housing to the exhaust manifold. I used sealer on both sides of the gasket. I put the top of the thermostat housing together without the thermostat in because when I flush it out I did not want any sediment to get fouled in the thermostat. Once the engine is flushed, install the thermostat.

Exhaust Manifold
There are 4 nuts and/or bolts holding on the exhaust manifold. Replace the gaskets and torque the bolts. Specs in the manual.

Intake Manifold
Next I re-attached the intake manifold. I replaced the gaskets but did not use any sealer on them. Torque them as spec’d. Than I re-attached the fuel filter bracket.

Alternator Bracket
Hold up the bracket in place and get a length of the ½” diameter hose you need to connect the exhaust manifold to the Alternator Cover Bracket. I used new hose and hose clamps. You have to fit the hose into the fittings as you re-install the cover. I used sealer on both sides of the gasket.
Note: You can install the hose afterwards but it is much harder.

Carefully examine the cylinder walls and pistons when you pull the head. There are 8 large (1/2” diameter approx.) water ports going from the block to the head. Many of them were reduced in size from the build-up of the salt and corrosion. I used an ice pick and long thin screwdriver to scrap out as much as I could. I than used a compressor to blow out as much of the loose debris as possible. Again, I pulled out quite a bit of crap. I’m sure that there is some loose that did not come out so I am taking some pre-cautions. (See note 1)
Top of Block

Views looking at top of block. If you can see the 6 small holes, 2 on top, 2 in between and 2 below the pistons were completely blocked and had to be drilled out. The 6 – ½” dia. water ports were also reduced in size and had to be opened up.
There are also 6 smaller holes that are in pairs, 2 in front of the piston, 2 in between the cylinders and 2 aft of the cylinder. These bring cooling water down to the metal that holds the bearings for the crankshaft. All 6 of mine were blocked so completely that I used a drill bit ( #29 or 5/32”) to drill out the crap. To get the drill in to 2 of the holes, I had to remove the 2 studs that hold the head and the rocker arm assembly. I took these out with the help of visegrips and a pipe wrench.

Once I had the ports cleaned and the studs out, I used some 600 wet/dry paper to clean up the top of the block. I used WD-40 instead of water. I re-installed the studs and am ready to re-install the head.

Notes: 1) I plan to flush the engine out in the back yard before re-installing it. I will connect the garden hose to the water inlet on the stbd side of the engine and run water through it gently before placing a thermostat in it. I will connect short hoses to the thermostat to keep the water away from the engine. This is in an attempt top flush out any particles of rust and corrosion that I could not get out of the block. Without doing this they could clog the thermostat or get into the return and damage the water pump.

2) I did this during the winter and I kept the block in the garage. I kept the block sprayed down with WD-40 to keep the moisture off the piston and cylinder walls
Fuel Filter
Replace screw on fuel filter with Universal Fuel Filter #298854. Fram P7514

Fuel Injectors
When I removed my fuel injectors, the nozzles were very dirty. Since I did not know anything about them, I decided to bring them to the pro’s. I brought them to Boston Fuel Injector in Smithfield, RI. They cleaned them, replaced the nozzles, and painted them. It took them 2-3 days. They take the numbers off the nozzle that you give them so them know what nozzle to use to replace it with. If you are into it, the parts are available to do it yourself.

Alternator Bracket Cover
There is a cover on the front of the head that holds the Alternator. It also is a bypass for cooling water to flow to the other side (stbd) of the head. There is a thin groove in the cover that allows water to flows across to the small hole in the block where the water enters on one side and to a bypass that carries the water to the exhaust manifold. The temperature sensor screws into the front cover. Remove the 4 bolts that hold on the cover and clean this. I also replaced the sensor while I was at it. I was told they last forever, but I decided to change it anyway.
The alternator bracket is also the holds the water temperature sensor as shown above. There is an 1”x1”x1” recessed area where the sensor is but there is a little groove about 1” wide going to the right that is only about 1/8” deep. Mine was so incrusted that no water passed thru to the other side of the engine. I chipped out quite a bit of rust out of this. The top red fitting is the water bi-pass to the exhaust manifold.

NOTE: When I removed mine, the groove in the cover was completely blocked as well as the hole where water enters the head. I used an ice pick and a screwdriver to clean this out. Cooling water was not reaching that side of the engine. I strongly recommend that this is checked every years or so, for the groove in the cover is only about 1/8” thick.

Temperature sensor
On the alternator bracket is also the temperature sensor for the engine. While I was told that it rarely goes bad, I chose to replace it. One of my concerns was the temp of the engine, so I figured if I go this far, why not replace it. Put Teflon tape or thread sealer on it and screw it back in. The temperature sender sensor is part # 299066

Oil Pressure Sensor
The oil sender is on the port side behind the exhaust manifold. It just screws into the block. I replaced mine just as a pre-caution. Put some Teflon tape or sealer on the threads and screw it back in.
Note: The old sensor had a male electrical fitting to connect to the wiring harness. The new sensor has a screw connector so I cut the old fitting off the wiring harness and soldered on a new connector.

Water inlet to Block & Water Drain
There is a fitting on the stbd side of the engine where the water enters the block from the water pump. At the top of the fitting was a bleeder valve used to drain water in cold weather. It was the kind that has the ‘wings’ that you turn. The wings were rusted so they bent when you turned them. For the last 5 season since I had the boat I did not use it, for that fact, know it was there. I decided not to replace it so I put a 1/8” brass plug in its place.
While you’re at it…
Fuel Tank Gauge Sending Unit
By boat came with a 15 gallon fiberglass fuel tank that did not have a fuel gauge. I decided to install one since I had the engine out and I could get at it easier.

Appanoug Harbor Marina… John Dickerson 401-739-5005
John is the man. They sold the Universal model 5411 to C. E. Ryder for the Sea Sprite 28’. John has all the parts, gaskets, engine paint, sensors, valves, etc. He has it all. He also has used blocks, heads, covers, pans, etc for the 5411. Located in Warwick, RI.

Boston Fuel Injectors
356 George Washington Highway Smithfield, RI 02917 401-231-0210
Pedro Monteiro, Manager
About the only place in Rhode Island that specializes in injectors. Since this is the heart of the engine, I figure bring it to the pro’s. They charge $25.00 per injector for labor and the new nozzles were about $13.00 each, totaling $78.90 completely rebuilt.

General Armature Broad Street Providence, RI
I dropped off by starter and my alternator for them to check & clean. I picked it up a couple of days later and they looked brand new. They went through them but I don’t know what they did. The person who did the work was not there when I picked them up. I highly recommend them. The cost was $45.00 each.

Simplex Machine 1011 Westminster Street Providence, RI 401-331-3500
They are a machine shop that does a fair amount of marine work. They were easy to work with. I dropped off the head in pieces to have them check it as well as clean the rust and salt out. I went back and dropped off the valves and the rocker arms so they could put it together and check the valve seats as well as the clearances. I also dropped off new freeze out plugs for then to install and new valve guides in case they needed them.
Appendix A Removal Derrick

I took 4 – 2x4x16’s and nailed 2 together for the uprights for each side. I took 2 2x6x10’’s for the top and bolted them and the 4×4’s together to form a derrick. I had some plywood so I made some gusset on each side and I also used a piece of ferring to cross brace it so it would not wrack. I dug a hole on each side of the boat about 10” deep for the 4×4 feet to sit in so that they would not kick out when we took a strain picking up the engine. The holes were approx. 3 feet aft of the winches. Then, I drilled a hole in each side at the ends of the 2×6 and ran my jib sheets to them from the blocks. We could now control the angle of the derrick easily. We moved the engine to the transom and I used my boomvang tackle to raise the engine (we picked up the engine and used the vang to take up the load once we lifted it above the stern rail. (a come-a-long or chain fall would also work). We eased out the jib sheets and the engine eased out over the stern and we lowered it down with the vang. It worked like a charm. It took about an hour to build and set up. Three of us lowered the engine down in 10 minutes. The whole process too work so well and was so easy I can’t wait till the spring when she has to go back in. We will get a come-a-long to do the lifting when we re-install.


Appendix B

Replacing the Cutlass Bearing (spring 2000)

Removal of the cutlass bearing can be a project, unless you get right into it and go for it. It requires about a day to do the job.
First, I tried to get the prop off. I unscrewed the first nut easily, but a pipe wrench with a 4-foot bar attached could not budge the second nut. So, on to the starboard locker and attack the hub and shaft from inside to see if I could separate them. It is not necessary to get the prop off. The 2 bolts holding the shaft in seemed to be one with the hub, so out came the turbo touch with mapp gas. After 15 minutes of heat, (each side) I backed off the 2 bolts, a major victory, or so I thought. The next step was to get the shaft out of the hub. Since there is not much room to work and I am not as small as I once was, this turned out to be a chore. After a day or so of heating it and tapping it to break the corrosion, nothing!! So, not to be beaten, I made a steel plate that bolted to the back of the hub. In the center I drilled a ¾” hole and welded a ½” nut to it so I could push the shaft out with a ½” bolt. Fool proof, or so I thought. After an another afternoon of heating and banging the hub and turning the ½ bolt, I was the beaten. I showed it when I pulled out my sawzall and CUT the bronze shaft at the hub. It came out then!!
Note: There is a key way in the shaft and hub so you can not try to twist the shaft out of the hub. It must come straight out.

Now that the shaft was out, I brought it all to Bayview Marine in Warwick, RI and had them made a new shaft for me as well as get the cutlass bearing. They had to order the bearing because it is not a common size. It took about 2 weeks to get the shaft but they were busy at the time, mid April.

Removal Method 1
To remove the cutlass from the shaft log, first sand around the fiberglass to find the 2 or 3 set screws that are threaded into the glass and keep the bearing in place. They might be visible. If you can find them, remove them with an Allen wrench. You can now get a puller in to the bearing to pull it out. You can use a threaded rod with some washers and a nut on the inside of the bearing. Obviously you need to make sure that the washers hit the brass collar of the bearing. Than, either you get a weight to act as a slide hammer and bang it out or you need to pull it out with the threaded rod. To do this, you must fashion a brace of some sort that is approx. 5” away from the end on the bearing. (see below). Than all you need to do is tighten the nut on the outside and it should pull the bearing right out.

Removal Method II
You can not find the set screws soon to plan B. I took out the sawzall again and put in a metal cutting blade. Insert the blade into the bearing and hold it flat to the bearing. I cut through on one side than cut through in 3-4 other places. The bearing fell right out, with the help of some vicegrips. It is important that you hold the blade parallel with the bearing so you do not cut into the shaft log. It took about an hour with you taking your time.
Once you have the pieces of the bearing out, just look inside and you will see where the set screws are. Remove them from the inside the shaft log if you wish. I used a pair needle nose visegrips to turn the out. Clean up the inside of the shaft log with a piece of sandpaper.

Re-installing the Cutlass Bearing

First, unless you removed the set screws from the outside, and the threads were in good shape and you can re-install the setscrews, you will have to install new ones. To do that, I drilled 2-3 new holes and tap them to receive the set screws. I used a 3/16” drill bit and a ¼”- 20 tap to rethread the holes. Make sure you get Stainless Steel set screws when you replace them. The bearing can go in either way. You tap the bearing in until it is flush with the end of the shaft log. I put a band of 3M 5200 adhesive caulking around the last inch as I tapped it in. They say you do not have to do that, but I did anyway. Once the bearing is in, you replace the set screws. Be careful not to over tighten them or they will strip the threads in the glass.

NOTE: It was recommended to me that I grind a small flat spot on the outside of the bearing where the set screws will seat once installed. So, I measured how far in the set screws were from the end of the shaft log and drew a ring around the bearing with a black magic marker that same distance. I than tapped it in to within a ¼” of the ring around the bearing. I than marked with the magic marker the 3 locations of the set screws. I than took a small hand held grinder and lightly flattened a small area where the set screws would seat when tapped all the way in. This would keep the bearing from turning with the friction of the shaft. Finish tapping the bearing in and tighten the set screws. Re-insert the shaft through the bearing and re-attach the hub. Re-connect the hub to the flange on the transmission. Re-install the prop and add a new zinc and your good to go another 10 years.
NOTE: If you are thinking about replacing yours: (at least for the 28’SS) cut the shaft from the get go. The shaft costs about $100.00, but you will save twice that in aggravation. Order the cutlass bearing ahead of time and have it in your hand before starting. My cutlass bearing was made by Apex : 7/8” shaft x 1 3/8” OD x 3 ½ long. The shaft was about 7/8” x 24”(approx., I forget)

Installing fuel sending unit into fiberglass tank

The fiberglass tank in my 28’ SS was fiber glassed in so there was no easy way to get at it. You can fit an offset drill in between the tank and the sole of the cockpit. Caution: There is a fiberglass divider in the center of the tank running fore & aft that you have to be careful of. You obviously will not be able to install the unit there and than you will have to repair the glass work and start over. I was lucky and missed it.

I knew that I was going to be doing it in the spring as I did not top off the fuel tank when I winterized it as usual. I drilled a 1 ½” hole (check the sending unit to see what size hole for yours) on the stbd side about 2” aft of the fuel pick-ups. . Once I drilled out the center hole for the float to fit through, I placed the unit in and made sure that when the float raises it will not be obstructed.

Then I drilled the 5 pilot holes for the mounting screws. I suggest that you dry fit the sender with the screws before you install it. My tank was about 5/16” thick and it takes a lot of torque on a #6 screw. I had one snap because I did not try the screws first.

The fiberglass on the tank was laid up by hand and was uneven. When I tried to sit the flange on the top on the tank, it would not sit flat. I took a 5” offset grinder and flattened a small area where the sending unit would fit. This assured a good seal when installing it.

The sending unit comes with a gasket that sits between the flange and the tank. I thought that it could be a problem, so I did away with it. There is also an O ring around the center bolt that holds the float to the flange. I unbolted it and put a small amount of 3-M 5200 around the bold and tightened it up again.

Next, I took a small hand pump and pumped out all the fuel in the tank. It had been 22 years since the tank was cleaned or drained (since new), so on top of all the fiberglass dust I got in the tank, there must be other crap that made it in over time.

I used 3-M 5200 to seal the flange to the tank an used 5 – ¾” #6 Philip head screws to fasten the flange down. The electrical connections are easy and are spelled out on the instructions.

Next came time to fill the tank. There are a few things I wanted to know: first, how much fuel is needed to reach the pick up tube, and second, how many gallons does it tank to fill ¼, ½, or ¾ of a tank. So, I placed a hand pump on the pick up and started to fill the tank, gallon by gallon. It first started to suck fuel at about ½ gallon.

I than filled the tank 1 gallon at a time and took notes where the needle on the gauge was after each gallon. That will allow how many gallons I have at 3/8 of a tank and know that she will run dry.

Universal Atomic Diesel
Model 5411
Owners Manuel
Service Manuel
Parts Manuel
Rebuilding Notes