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water in cylinders and oil - MerCruiser 5.0 MPI -- Need help finding culprit

ptudozer said:
Yep, manifolds, risers and elbows will be replaced. Inspected butterflies, all looked good. Will be adding all new worm gear clamps as well.
Parts should be here Friday or Saturday.


Regarding the oil change after about 10 hrs or so... already have the oil and filter for it.
Lastly, does anyone have any insight why the water exiting the exhaust had one side cooler (by about 20 degrees) than the other side?
I'm just curious if this is an indication of any other issue, or maybe nothing.

Thank you all
Click to expand...

That is normal, there are hundreds of posts here asking the same thing.

Water flow takes the path of least resistance......

Also the hotter side manifold/elbow may have issues. Thus the suggestion to replace all on both engines
 
ptudozer said:
Yep, manifolds, risers and elbows will be replaced. Inspected butterflies, all looked good. Will be adding all new worm gear clamps as well.
Parts should be here Friday or Saturday.


Regarding the oil change after about 10 hrs or so... already have the oil and filter for it.
Lastly, does anyone have any insight why the water exiting the exhaust had one side cooler (by about 20 degrees) than the other side?
I'm just curious if this is an indication of any other issue, or maybe nothing.

Thank you all
Click to expand...
Temp difference between sides is fairly normal more indicative of trailer not being level and more cooling water going to one side or another, or if used salt water exhaust components flow restriction. Either way 20 degrees is nothing to sweat
 
Dieter said:
Temp difference between sides is fairly normal more indicative of trailer not being level and more cooling water going to one side or another, or if used salt water exhaust components flow restriction. Either way 20 degrees is nothing to sweat
Click to expand...
Got another puzzle piece.
It's been a few days since I ran engine on the hose and performed the 4 oil changes.
Oil is nice and clear.
I removed all the manifolds and Risers. Noticed that the exhaust port and valve on #2 were wet, #4, 6 &8 were nice and dry. Inspected #2 cylinder with camera, could see very tiny bubbles (looked like sweat beads) on top of piston. No water pooling, the rest of cylinder was dry.
Inspected the manifold that I just removed --this is the one from the starboard engine, I used to get port engine started before parts arrived -- exhaust port for #2 was dry, but #6 port was wet. WTF?
Anyone has an explanation for why #2 exhaust port (on the head) would be wet and the others dry?

Thank you
 
ptudozer said:
Got another puzzle piece.
It's been a few days since I ran engine on the hose and performed the 4 oil changes.
Oil is nice and clear.
I removed all the manifolds and Risers. Noticed that the exhaust port and valve on #2 were wet, #4, 6 &8 were nice and dry. Inspected #2 cylinder with camera, could see very tiny bubbles (looked like sweat beads) on top of piston. No water pooling, the rest of cylinder was dry.
Inspected the manifold that I just removed --this is the one from the starboard engine, I used to get port engine started before parts arrived -- exhaust port for #2 was dry, but #6 port was wet. WTF?
Anyone has an explanation for why #2 exhaust port (on the head) would be wet and the others dry?

Thank you
Click to expand...
Leak in exhaust port of head
 
ptudozer said:
Would you just buy new heads or have the current ones checked out at a machine shop?
If you were going to purchase new heads, where would be the best and most reasonable place to (website) to purchase from? Would you purchase from RockAuto? This is the head I'm looking at and the gasket set
Click to expand...
Pressure test the cooling system (block and Heads) on that engine before you rip it apart.

Is it possible the manifold and riser you moved from one engin to the other is bad also ? does it leak at riser joint?

almost 20 yr old salt water engine would not be the strangest to have a leak in the exhaust side was it ever over heated?
 
Dieter said:
1. Pressure test the cooling system (block and Heads) on that engine before you rip it apart.

2. Is it possible the manifold and riser you moved from one engin to the other is bad also ? does it leak at riser joint?

3. almost 20 yr old salt water engine would not be the strangest to have a leak in the exhaust side was it ever over heated?
Click to expand...
1. How do you perform a cooling system pressure test? I can plug some of the hoses that were connected to the manifolds, but how do I prevent pressure from escaping the raw water inlet hose to the raw water pump?

2. Anything is possible, but the starboard engine (good one) has no indication of moisture in any of the exhaust ports, so I don't think that is the culprit.

3. I had some overheating issues about 5 years ago, but the engine alarm went off at 185 degrees, so I don't think that was hot enough. That is when I learned about the Bravotis issues on these boats

If I have to get a new head, what do you think of the one listed on previous post from RockAuto along with the Gasket set?

Thank you
 
Took the head off, besides the rust in the #2 I don't see any obvious culprits ...although I'm a novice at messing with the internals of an engine.
I had the heads on these engines previously machined and I installed them and it worked for the past 6 years...maybe I did something wrong 6 years ago.
I'll take the head to the machine shop and have them check it out.

If anyone has any suggestions for what else to do or check, I welcome all advice.

Lastly, I can't remember where I got the bolt pattern and torque specs for the head bolts. Does anyone have that info?

I'm ordering the head bolts and gasket set, anything else I would need?

Thank you
 
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