Water in oil, milkshake.

[holorinhal]

Ok so, back in march we were at the river. Boat ran great all day long. Got back to beach and hung out for a few hours and when we went to start up to pit on the trailer, engine wouldn't bump over. Just clunk, clunk, like starter went bad. So i have asumed that bad starter. Ordered new starter.
yesterday, finally got time to take a look and tried to turn it over. At first, it did the same clunk, but then it started to turn over rough and kept trying and it started turning and sputtering like it wanted to start. Finally it started turning and fired up. After it fired up it was running fine.
tan for about 5-10 minutes. Great oil pressure temp good for hose.
decided to check oil and uhoh, milky oil.
The oil is milky but oil level is not over full, so not enough to raise oil level.
i pulled all the plugs, no water in any cylinders.
i did a compression test on all cylinders and compression was 135-150 on all cylinders except #5.
cylinder #5 was 65 psi.
In addition, i found yesterday that one of my internal exhaust tip flappers was stuck shut. Dont know how long it was stuck.
I have EMI Thunder, through hull exhaust manifolds and SS risers.
Could the stuck flapper have backed up water and got sucked in through the exhaust valve and got past rings in low cylinder.
My next step is to leak down that cylinder #5

 

[alldodge]

Got back to beach and hung out for a few hours and when we went to start up to pit on the trailer, engine wouldn't bump over. Just clunk, clunk, like starter went bad. So i have asumed that bad starter.

Your at the beach, is the bow on the beach, and was anyone sitting on the stern?

 

[Lou C]

Are you sure there was no water in the cyls? Because your symptoms seem to correlate with that....

 

[racerone]

Sounds like a cylinder filled with water.-----Blown head gasket.----Or cracked metal bits.

 

[Lou C]

I’d want to pull the manifold on the side with the stuck valve and see if you have corrosion on the valve stem; this points to water intrusion as a problem. Then I would test the manifold/elbow combo for water leaks.

 

[Scott Danforth]

You were hydro locked

 

[nola mike]

You were hydro locked

Or had a rusted/stuck valve, and bent a pushrod.

 

[nola mike]

Although your time frame sounds like hydro lock, could you bend a valve stem from that? Bent/stuck open --> poor compression

 

[holorinhal]

Your at the beach, is the bow on the beach, and was anyone sitting on the stern?

Yes the bow was on the beach cant say sir certain if any one was on the stern or not.

 

[holorinhal]

Are you sure there was no water in the cyls? Because your symptoms seem to correlate with that....

I did not see any water or fluid in the cylinders.
the plugs were dry. I turned the engine over with the plugs out on one side at a time to see if any thing pushed out and saw nothing.
i know the locked up symptom or stuck starter could be the same as hydra lock.
when i was working on it the other day, at first it was the same as at the river either locked up or stuck starter, but i kept bumping it and it finally started rolling over and then fired up.
once it fired up and running, it was running normal.
could it have just pushed any water past the rings and started turning over and when running milked the oil.

The thing that is odd to me is that when we parked at the beach, it was running fine and i simply turned off the key

 

[holorinhal]

I’d want to pull the manifold on the side with the stuck valve and see if you have corrosion on the valve stem; this points to water intrusion as a problem. Then I would test the manifold/elbow combo for water leaks.[/QUOTE
well that will be the first thing i do tomorrow.
ill take the riser off the manifold too to see if there is a gasket failure. I have a solid block of gasket at the riser jt. If that failed and let water into the exhaust cavity, could it suck water back into a cylinder?
wouldnt it suck water into all cylinders?

 

[holorinhal]

You were hydro locked

Well i certainly don't disagree! Its just odd that there was no sign of it till went to start back up a few hrs later. And that i was able to get the engine to turn over and fire up the other day. Could trying to rotate the engine have pushed the water past the rings int the crank case and then while running, milked the oil? Could that be why no sign ow water in cylinder?
any ideas on how it would hydro lock? Different ways other than reversion.

 

[holorinhal]

Although your time frame sounds like hydro lock, could you bend a valve stem from that? Bent/stuck open --> poor compression

Well i know hydro locked engines have been known to bend pushrods. I am sure that it could bend a valve and bend a rod also and yes i agree a stuck/ bent valve could very well be the reason for low compression.
but can a hydro lock possibly break piston rings?

 

[alldodge]

With your starting issues when trying to restart, water in the oil, I think water got in and drained down the walls. Once the motor fired up all the rest of the water went out the exhaust.

The exhaust flapper being stuck it would allow water out but it would be slower. Would also causing pooling on that side. No telling if it just gets stuck when the motor shoutd down from heat and opens back up when restarted

 

[vetting]

I had something similar happen a few years ago on a carbed 5.7 mercruiser. After a day of fishing, let the hose run on the deck of the boat to flush out the bilge. Bilge pump stopped working and lowered the back of the boat just enough for water to come up through the exhaust. Really hot head, put random cold water where its not supposed to be...equaled a small crack in the head. This allowed water in one cylinder only and was easily pushed passed the rings due to the other 7 cylinders being fine. When I was trying to diagnose the issue, it milked the oil for 3 straight oil changes in an hour but ran fine the entire time. Ended up removing the head from side that had the cylinder that was low on pressure and found the crack by the valve.

 

[Scott Danforth]

Well i certainly don't disagree! Its just odd that there was no sign of it till went to start back up a few hrs later. And that i was able to get the engine to turn over and fire up the other day. Could trying to rotate the engine have pushed the water past the rings int the crank case and then while running, milked the oil? Could that be why no sign ow water in cylinder?
any ideas on how it would hydro lock? Different ways other than reversion.

yes, trying to start it forces the water past the rings to the crank case

multiple ways to introduce water into a cylinder, here are a few off the top of my head

• run on - that little rattle and gasp at the end of an engine running on is it running backwards and sucking in water
• leaking exhaust elbow gasket - very common on salt water boats. this is why you must pull the elbows ever few years for inspection on a salt water boat.
• leaking intake from a rust thru, or a leaking intake gasket
• beaching a boat. many times forcing the bow on the beach, then having many people on the swim platform is enough to have the elbows/risers at the water line vs 13" above......then all you need is a slight wave.

not only can trying to start a hydro-locked motor break rings, it usually bends connecting rods

 

[holorinhal]

With your starting issues when trying to restart, water in the oil, I think water got in and drained down the walls. Once the motor fired up all the rest of the water went out the exhaust.

The exhaust flapper being stuck it would allow water out but it would be slower. Would also causing pooling on that side. No telling if it just gets stuck when the motor shoutd down from heat and opens back up when restarted

Yes i agree! I man thinking this is one likely senario.

 

[holorinhal]

yes, trying to start it forces the water past the rings to the crank case

multiple ways to introduce water into a cylinder, here are a few off the top of my head

• run on - that little rattle and gasp at the end of an engine running on is it running backwards and sucking in water
• leaking exhaust elbow gasket - very common on salt water boats. this is why you must pull the elbows ever few years for inspection on a salt water boat.
• leaking intake from a rust thru, or a leaking intake gasket
• beaching a boat. many times forcing the bow on the beach, then having many people on the swim platform is enough to have the elbows/risers at the water line vs 13" above......then all you need is a slight wave.

not only can trying to start a hydro-locked motor break rings, it usually bends connecting rods

I do agree with all those scenarios.

I haven't had any noticeable run on.

however i do see evidence of leaking riser gasket as i noticed today that there is streaking down the side of the manifold on the outside face, from the riser/ manifold joint, running down.
when i took the riser off the gasket was still in tact though.

the boat is a fresh water boat and has never seen salt and i have recently had the manifolds off and visually inspected them, not pressure tested though.

Doubt the water back up over the riser while beached, though.

 

[vetting]

So whats your next plan of action with the low cylinder?

Do you store in the water or trailer?

 

[holorinhal]

So whats your next plan of action with the low cylinder?

Do you store in the water or trailer?

I am pulling the manifold and riser on the Starboard side, and the valve cover, to see what i can see.
i will get cyl# 6 to TDC and run some air in tho see if any thing is coming out. At this point doing a leak down seems pointless as i know the percentage isnt really going to matter. I need to pinpoint where the compression is going.

oh and sorry but i initiall miss spoke on which cyl is low. It is actually #6 not #5. I cant figure out how to edit the post.
be back in a few!