Port side engine water cooling circulation

[lemor]

1
Engine year: 1987
make: Mercruiser
type: V8 5.7L
model: 350
serial number if poss: Not available

2 type of outdrive, Merc,Volvo,etc. - Not applicable

3 EXACTLY what it`s doing wrong, worded correctly so we can figure out the question.
The circulation of water is not occurring on the the engine's port side, meaning that there is insufficient amount of water coming out of the exhaust in comparison to the starboard side. The water that is coming out of the exhaust is extremely hot and is producing steam. The water pump and impeller was removed and reviewed and is in good working condition. It has been reinstalled, but the problem still exists. The engine is equiped and cooled by closed circuit fresh water. The strainer is clean and the sea-**** is open. What other things could be causing the problem?

 

[Bt Doctur]

Re: Port side engine water cooling circulation

the engine is fwd but are the manifolds?
Yes ,suspect clogged riser
No, suspect manifold and riser
clogged oil cooler
clogged heat exchanger.

 

[Don S]

Re: Port side engine water cooling circulation

An air leak anywhere in the water pickup to the pump will cause low water flow.
Make sure the cap on the sea strainer isn't leaking.
A piece of clear hose between the sea water pump intake and the strainer will show you if you have an air leak. LOTS of bubbles.
If that is clear, then BT may have your answer.

 

[lemor]

Re: Port side engine water cooling circulation

1) I made sure that there is no air leakage through the suggested test.
2) I took apart the heat exchanger and removed all debris (pieces of rubber accumulated over time from broken impellers and calcium deposit). This has improved the raw water flow through the engine and through the exhaust.

Originally, the water coming out of the exhaust was extremely hot and could not be touched. However, the water is not as hot now and can be touched for over a minute. There is still steam being produced and the amount coming out of the exhaust on the port side is not as much as the one on the starboard side. There is still room for improvement.

I was thinking to check the tube that runs from the seacock to the strainer to verify if there is any debris causing additional strain on the water flow.

PLEASE, are there any other suggested next steps to consider in order to eliminate the problem with the steam and to increase the amount of water coming out of the exhaust on the port side?

 

[Don S]

Re: Port side engine water cooling circulation

Pull the risers and see if the water passages are plugged up.

 

[lemor]

Re: Port side engine water cooling circulation

Team -
We are still having problems with the port side engine overheating and producing excess amounts of steam coming out of the exhaust. This is what we did based on your recommendations:

1) Changed the water impeller with a new one.
2) Replaced both risers with new ones (including new gaskets). After changing the risers and the engine is still over heating after taking her out.
3) We replaced the thermostat with a new, but we have not taken her out yet.

In addition, it is important to mention that there is no water in the oil.

What else could we possibly do? We have already run our parts replacement bill over $500. Any additional recommendations would be greatly appreciated!!!

 

[lemor]

Re: Port side engine water cooling circulation

We resolved the issue by diagnosing the passage way through the oil cooler. It was clogged up with broken pieces of impeller rubber!!! We are all set to go!!