Water Intrusion Puzzle

[simpleur2]

I'll try to make this as non-confusing as possible . I'm trying to find the source of the water that is affecting the engine. The engine is a 5.7-liter Volvo Penta V8, inboard/outboard.

Issue:

Boat randomly, inconsistently sputtering and hesitating under power. White milky smut on oil filler caps and in blow by tubes (if you clean the tubes and run it you can see water droplets in the tubes. It's obvious water is getting into the intake causing the boat to run like described).​

what I found:

Milky snot on oil filler caps, underside of valve covers and in blow by tubes to carburetor.​

The two center exhaust ports and valves on the starboard side are rusted (oh ****) port side is nice.​

Water sitting in the same two cylinders (small amount, Double oh ****).​

There is not a drop of water in the engine oil.​

What I've done so far:

Pumped 2 liters of fuel from the supply line on the fuel tank to see if water is present. No water present.​

Pressure tested exhaust manifolds and risers separately and assembled. (Newer Chinese made exhaust manifolds and elbows. Castings suck but they held 50 lbs. of air). Only ran these a few times since new.​

What I'm thinking of doing:
The next step I can see is to replace the head and intake gaskets. I sure don't want to go there just to find out there is something fishy with those new manifolds even though they held pressure (issue occurred after I installed them, can't remember if immediately or not).

Looking for experienced opinions:
Can the exhaust ports rust from water entering the intake? My brain says no after its burned or steamed with the fuel and sent out the exhaust.

Do the rusted exhaust ports indicate the water is coming from the exhaust manifold side?
If so, how can the water get into the intake and effect the way the boat runs from the exhaust port side, how's it going to get to the intake from there?

Although I highly doubt it does anyone think a crack in the cast iron manifolds or risers could hold 50 lbs. of air and open when the engine gets hot?

This is an older engine, but always ran great. I wanted to bounce this off some of you guys who may be long time Volvo Penta mechanics. You guys might just say "bite the bullet, inspect the water jackets and change the gaskets, if it still does it throw those Chinese manifolds in the garbage and get new ones". It's just so much work if it's the stupid manifold or riser on that side.

Thanks

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[Dillusion808]

Yes check manifolds. Prolly one of the cheaper fixes if thats it. How did you test it to 50psi without removing them.

If not could be head gasket or cracked block. Do you live somewhere were it needs to be winterized?

 

[flashback]

Head gasket has been compromised maybe. Pressure test the cooling system and you may find a breach .

 

[Lou C]

You need to get to the bottom of this right away, you aren't getting water from the intake, you're getting water in the oil even if its not showing on the dipstick yet, that's what the mayo like coating is under your valve covers and that's what's showing up in the breather hoses.
Pull the manifolds, evaluate the condition, clean up the mating surfaces, and see what you have.
I bet if you removed the intake manifold, you'll see the same thing in the cam valley as what's under the valve covers.
You might have blown head gaskets, I'd deal with the exhaust issue, then run the engine, get it good and hot, pull the plugs, crank it over to see if you have water in a cylinder(s) if not great, if so then if the manifolds are good, likely blown HG. I had this on mine, thought it was the manifolds but it wasn't they tested out fine. Overheat damage, HGs blew a few years later.
When you get water in the oil it usually shows up on the dipstick last. It shows first under the valve covers.

 

[cyclops222]

Cold engines make Cream Cheese in valve covers. See if a idiot removed the thermostat system parts.............. Typical idiot ideas.

 

[Scott Danforth]

Most probable sources of water intrusion:
Failed exhaust elbow gasket
Cracked block/heads from improper winterizing
Cracked block/heads from overheating

 

[simpleur2]

Yes check manifolds. Prolly one of the cheaper fixes if thats it. How did you test it to 50psi without removing them.

If not could be head gasket or cracked block. Do you live somewhere were it needs to be winterized?

 

[simpleur2]

I tried to upload a picture of how I tested the manifold and riser but its telling me the file couldn't be written to the server .

I did pull the manifold and riser off and tested them assembled. I pressurized he exhaust chambers, if they were compromised air should have escaped from the water discharge at the end of the elbow or the water inlet on the end of the manifold. no air escaped, they held at 50 lbs.

 

[simpleur2]

Head gasket has been compromised maybe. Pressure test the cooling system and you may find a breach .

Good idea, never thought to pressure test the cooling system. If that holds pressure the head gaskets and intake should be okay (I'm assuming).

 

[simpleur2]

You need to get to the bottom of this right away, you aren't getting water from the intake, you're getting water in the oil even if its not showing on the dipstick yet, that's what the mayo like coating is under your valve covers and that's what's showing up in the breather hoses.
Pull the manifolds, evaluate the condition, clean up the mating surfaces, and see what you have.
I bet if you removed the intake manifold, you'll see the same thing in the cam valley as what's under the valve covers.
You might have blown head gaskets, I'd deal with the exhaust issue, then run the engine, get it good and hot, pull the plugs, crank it over to see if you have water in a cylinder(s) if not great, if so then if the manifolds are good, likely blown HG. I had this on mine, thought it was the manifolds but it wasn't they tested out fine. Overheat damage, HGs blew a few years later.
When you get water in the oil it usually shows up on the dipstick last. It shows first under the valve covers.

 

[simpleur2]

The manifolds are new, only 5 or so fishing trips on them. I pressure tested them and they hold air. I don't think it's possible to have a crack that can hold 50 lbs. of pressure cold and start to leak when hot. Pretty sure I have the manifolds eliminated as the problem. It just bugs me because it happened a little while after the manifolds were replaced. The riser has a spot that looked like they took a grinder to it. Like there was a hole in the casting and they welded it up. But it's flowing water and holding pressure. No air breaching into the water side. Still bugs me though.

 

[simpleur2]

Cold engines make Cream Cheese in valve covers. See if a idiot removed the thermostat system parts.............. Typical idiot ideas.

Thermostat is there, the boat runs around 180 degrees

 

[simpleur2]

Yes check manifolds. Prolly one of the cheaper fixes if thats it. How did you test it to 50psi without removing them.

If not could be head gasket or cracked block. Do you live somewhere were it needs to be winterized?

Oh yeah, the boat doesn't have to be winterized where I live.

 

[Lou C]

The manifolds & elbows can be new but the manifold to elbow gasket can still leak water. I’m not sure why yours hold air pressure but may be leaking water. Did you check for flatness with a mechanics straight edge & feeler gauges before installing? Some need to be dressed with a mill bastard file. If that elbow doesn’t look right to you replace it! If the engine is running at 180* and you have Mayo under the valve covers you have got water in the oil!
When my HGs blew I changed the oil 4x to get it all out.
If your manifolds truly don’t leak water but you have rusty exhaust ports the other possibilities are a blown HG on that side & a cracked or corroded cyl head…it’s water in the oil that’s coming from SOMEWHERE you just have to find out. One thing I did with my manifolds to test them was to assemble them & then test off the engine by propping them up level & hooking up a water hose. Turn on the water and watch the ports that line up with the exhaust ports in the cyl head. You could even heat the manifold carefully with a heat gun to simulate a warm engine. That way you can tell for sure!

 

[simpleur2]

The manifolds & elbows can be new but the manifold to elbow gasket can still leak water. I’m not sure why yours hold air pressure but may be leaking water. Did you check for flatness with a mechanics straight edge & feeler gauges before installing? Some need to be dressed with a mill bastard file. If that elbow doesn’t look right to you replace it! If the engine is running at 180* and you have Mayo under the valve covers you have got water in the oil!
When my HGs blew I changed the oil 4x to get it all out.
If your manifolds truly don’t leak water but you have rusty exhaust ports the other possibilities are a blown HG on that side & a cracked or corroded cyl head…it’s water in the oil that’s coming from SOMEWHERE you just have to find out. One thing I did with my manifolds to test them was to assemble them & then test off the engine by propping them up level & hooking up a water hose. Turn on the water and watch the ports that line up with the exhaust ports in the cyl head. You could even heat the manifold carefully with a heat gun to simulate a warm engine. That way you can tell for sure!

Good idea, never thought to pressure test the cooling system. If that holds pressure the head gaskets and intake should be okay (I'm assuming).

The cooling system held 15 lbs. Now I'm really stumped.

 

[simpleur2]

The manifolds & elbows can be new but the manifold to elbow gasket can still leak water. I’m not sure why yours hold air pressure but may be leaking water. Did you check for flatness with a mechanics straight edge & feeler gauges before installing? Some need to be dressed with a mill bastard file. If that elbow doesn’t look right to you replace it! If the engine is running at 180* and you have Mayo under the valve covers you have got water in the oil!
When my HGs blew I changed the oil 4x to get it all out.
If your manifolds truly don’t leak water but you have rusty exhaust ports the other possibilities are a blown HG on that side & a cracked or corroded cyl head…it’s water in the oil that’s coming from SOMEWHERE you just have to find out. One thing I did with my manifolds to test them was to assemble them & then test off the engine by propping them up level & hooking up a water hose. Turn on the water and watch the ports that line up with the exhaust ports in the cyl head. You could even heat the manifold carefully with a heat gun to simulate a warm engine. That way you can tell for sure!

Tried the water hose test, no water leaking into the ports. Nothing is ever strait forward . Not sure what direction to go in now, guess the shotgun approach and do all the gaskets and replace that funky looking exhaust manifold.

 

[simpleur2]

The cooling system held 15 lbs. Now I'm really stumped.

I was mistaken, after a while some air was lost in the cooling system. I stuck my ear to the rusty exhaust port and I could hear air leaking into the cylinder. Looks like a head gasket. I'm pretty sure this engine is the original engine in this 1984 boat. Who knows what the water jackets are going to look like. I should take bets on how many bolts are going to break and round off. pray for me

 

[Lou C]

well
I took my 1988 apart in 2017 due to bad head gaskets, it had been run raw water cooled in salt water about 15 years at that time, I used my De Walt 1/2" impact to get them out, and not one broke, so there's hope! I actually had more trouble with the intake manifold, it was stuck on there like Kryptonite. Not the bolts but the old gaskets. Original engine never been apart before then. The thing that took the longest time was cleaning out the cyl head bolt holes in the block and cleaning the block deck well enough for the new gaskets to seal.
The heads needed to be replaced, cracked from a previous overheat and the cooling passages were eroded from salt water use.
Put it back together with Fel Pro gaskets and a set of reman heads, and a new Barr Marine exhaust and it's still running fine 7 years later.

 

[simpleur2]

well
I took my 1988 apart in 2017 due to bad head gaskets, it had been run raw water cooled in salt water about 15 years at that time, I used my De Walt 1/2" impact to get them out, and not one broke, so there's hope! I actually had more trouble with the intake manifold, it was stuck on there like Kryptonite. Not the bolts but the old gaskets. Original engine never been apart before then. The thing that took the longest time was cleaning out the cyl head bolt holes in the block and cleaning the block deck well enough for the new gaskets to seal.
The heads needed to be replaced, cracked from a previous overheat and the cooling passages were eroded from salt water use.
Put it back together with Fel Pro gaskets and a set of reman heads, and a new Barr Marine exhaust and it's still running fine 7 years later.

I'll let you know how it turns out.

 

[simpleur2]

well
I took my 1988 apart in 2017 due to bad head gaskets, it had been run raw water cooled in salt water about 15 years at that time, I used my De Walt 1/2" impact to get them out, and not one broke, so there's hope! I actually had more trouble with the intake manifold, it was stuck on there like Kryptonite. Not the bolts but the old gaskets. Original engine never been apart before then. The thing that took the longest time was cleaning out the cyl head bolt holes in the block and cleaning the block deck well enough for the new gaskets to seal.
The heads needed to be replaced, cracked from a previous overheat and the cooling passages were eroded from salt water use.
Put it back together with Fel Pro gaskets and a set of reman heads, and a new Barr Marine exhaust and it's still running fine 7 years later.