1988 omc 5.7 how do I run it outside of the boat

[ab59]

I put this on the end of another thread but guess I should have opened a new one so here goes. I am finishing up putting all the jewelry on this new engine that i will install soon. I had some corrosion in the manifolds that I cleaned out but it as a little flaking going on so I would like to run the engine outside the boat while still sitting on a pallet . I have a closed cooling system so how would i go about rigging this engine to run as far as water goes ?? any one already done this before ??

 

[tpenfield]

Everyone does this. Lots of youtube videos of engine running on pallets, etc.

Depends on how fancy you want to get . . . you need power to the ignition and main engine wiring. . . momentary power to the starter solenoid . . . and water to the open side of the closed cooling system.

Here is my engine running on a dolly that I made for it.

 

[ab59]

so let me bounce this off of you- I connect a water hose onto the lower front of the manifold and put water to in until i see water come out both sides then start the engine , rite ? So I do not see your closed system tank hooked up , do you have one or are you test running without it to simplify running the engine. i need to set my timing at this point as well .

 

[ab59]

one more thing the shutters are gone in the Y exhaust pipe, do I really need them ??

 

[tpenfield]

so let me bounce this off of you- I connect a water hose onto the lower front of the manifold and put water to in until i see water come out both sides then start the engine , right ? So I do not see your closed system tank hooked up , do you have one or are you test running without it to simplify running the engine. i need to set my timing at this point as well .

No . . . you would hook the water to the inlet hose of the engine that water normally would come from the outdrive. The water should go up through the heat exchanger of the closed cooling system and out the exhaust. It is like making the engine 'think' it is in the boat.

The engine I have in the video is an open cooling system, but there is no significant difference in the water hook-up aspect. If your engine has a sea water pump, it should provide plenty of flow. If not, you will want to make sure you have enough water pressure from the garden hose to get water flowing through the cooling system. Usually domestic water supplies have enough pressure.

 

[Scott Danforth]

one more thing the shutters are gone in the Y exhaust pipe, do I really need them ??

YES

 

[ab59]

I am clearly in the dark on this. I thought that since I have antifreeze in the tank that NO water was exchanged between fresh water and the normal self contained system that is provided by the water pump. I do not know what a sea water pump is and do not think one is on this engine. Looking at the schematics of the different types of closed systems makes me even more confused because it looks like I may have some missing components although if did not seem so upon disassembly. I also thought that no water was drawn into the system from the water that the boat sat in and only pushed out exhaust from the engine through the bottom of the Y tube.
I may have to brake down and buy a manual for this year model. I have one but it is for models up to 1986 so I don't know if they would be the same.

 

[tpenfield]

Maybe you can post a couple pictures of the engine, etc.

1) The antifreeze (coolant) runs through the engine and the heat exchanger (tank) . . . so the coolant gets hot from running through the engine. . . something must cool it down or it will continue to get hotter.

2) Water is drawn from the lake/ocean (raw water) through the outdrive and up to the heat exchanger (tank). Within the heat exchanger there are many small tubes that run through where the coolant resides, The raw water runs through these small tubes, keeping it separate from the coolant. The coolant and the raw water never meet, but they exchanger heat. So, the hot coolant cools down and the raw water heats up.

3) the raw water, now hot, needs a place to go . . . so it continues along its journey to the exhaust and goes out the Y-tube back into the lake/ocean.

4) the coolant (now cooled) goes back into the engine to grab more heat, making it hot again. . . and the process continues.

As to your specific questions/comments . . .

"I thought that since I have antifreeze in the tank that NO water was exchanged between fresh water and the normal self contained system that is provided by the water pump." No water is exchanged only the heat from the coolant and water are exchanged. The heat from the coolant goes into the water.

"I do not know what a sea water pump is and do not think one is on this engine. " There is a pump either in the outdrive or on the engine. This is in addition to the 're-circulating pump' that is on the front of the engine, similar to what is in a car engine. The sea water pump's job is to bring the lake/sea water up to the engine . . . in this case it brings it to the heat exchanger, as that is where the exchange of heat is taking place.

"I also thought that no water was drawn into the system from the water that the boat sat in and only pushed out exhaust from the engine through the bottom of the Y tube." Where would that water originate from, if it did not come from the lake/ocean?

I hope this further explanation helps. A closed cooling system on a boat engine is essentially 2 cooling systems and sets of plumbing. 1 for the coolant and 1 for the sea water. The heat exchanger is where the coolant transfers its heat to the sea water.

 

[ab59]

you know , it is strange how good ones mind feels when they finally begin to understand the solution to a problem. I will go to my other thread about cooling system to pursue this further .

 

[ab59]

More stupid questions about hooking up the water for testing. I get the supply line but I left the oil cooler and hoses in the boat so stupid question is , do I need to run water through the oil cooler or can I bypass that and hook up to where the cooler line enters the heat exchanger ? Looks like I will need to take the belt off the power steering pump for this as well.

 

[tpenfield]

Ideally, you would want the oil cooler, but for running on a pallet with no load, I'm thinking it is not necessary. It is just better to have the engine all together when doing a test run.

​Correct, P/S belt won't be needed for testing.

 

[ab59]

ok i will look and see what it takes to get the oil cooler out of the boat and hook it back into the system.

 

[ab59]

everything is hooked up including the oil cooler I got out of the boat and waiting for the plugs I ordered to get here.Almost wish that I had just bought whatever the local auto parts store had on hand for a Chevy 350, almost.

 

[ab59]

OOps , I just realized that I need to feed the distributor some juice . How did you rig the battery feed to the distributor and I have electronic dist. .

 

[ab59]

More stupid questions--below you will find pictures of a coil and something that I am not familiar with so I am asking anyone what this is and what it does . It almost looks like some kind of a second coil but does not connect to the distributor .

 

[ab59]

thats ok I found one one eBay, it is a shift assist not sure of exactly what it's function is and or how it helps shifting but at least I know I can test run the engine without it connected.