Water in Oil (Again) Head Scratcher

[Lou C]

15 psi should be enough that’s what most automotive systems use

 

[Lou C]

i also found when tightening the intake manifold with the marine gaskets that just snugging them down tight to a guestamate was better result than a torque wrench to 11 foot pound which seemed to be a bit loose for my liking. .

edit to answer your last post. ,split the risers from the manifolds and blank off there.

That 11 ft lbs always seemed too loose to me yet I know that’s what GM specified. The pre Vortec was 30-35 ft lbs. Just seemed odd for it to be 1/3 what the pre Vortec was. Was there that much a difference deference in the gaskets?
I never had one problem with the gaskets on the pre Vortec

 

[Scott06]

other possible thoght is head bolts that go into water jacket if they were sealed…

 

[Lou C]

True you have the use sealer on them

 

[stresspoint]

That 11 ft lbs always seemed too loose to me yet I know that’s what GM specified. The pre Vortec was 30-35 ft lbs. Just seemed odd for it to be 1/3 what the pre Vortec was. Was there that much a difference deference in the gaskets?
I never had one problem with the gaskets on the pre Vortec

hey Lou , yes , those alloy 4.3 gaskets i used the final time were quite solid as compered to the plastic felpro ones i originally used.
i found the same that tightening them gown more than spec when i used the thicker felpro marine gaskets on my 5.7.

it makes me wonder if that 11 foot pound is referring to automotive not marine and it was just followed on from there when the marine manufactured printed their service manuals.

OP , Scott06 has a good point there mentioning the head bolt sealing , no sealant would cause lots of water in the oil, however , ? you mention that you found water in the exhaust , is there any chance that water could have come in when you separated the exhaust risers.

 

[tpenfield]

I might have missed it, but when the engine was rebuilt, did the shop put a new camshaft in the engine? Just wondering if there is too much valve overlap.

 

[AMMO DAWG]

Update - Weather has been crap and work keeps getting in the way but I'm back on the investigation. Thought I would start with the manifolds and risers and hopefully eliminate them as the issue since they are virtually brand new. I rigged up a manifold and a blocker plate and pressurized both of them. After chasing links in my rig and a couple of the factory installed end plugs both manifolds held around 20 psi for an hour. I did a quick check of the surfaces of the manifold and rise and they seem to be square. I have a straight edge, what should I be shooting for as far as a max clearance? Tomorrow was going to focus on the risers, since I can't pressure test them I was thinking of installing a blocking plate and gasket and filling the cooling passage with acetone as I have read in other posts. Also, if the weather cooperates I hope to pressurize the cooling system tomorrow now that I have scabbed together a pressure manifold.

Tpenfield, the same cam was used for the rebuild, it was still in spec and good shape. Thanks for all the great advice and tips. More to follow, posted some pics of the pressure test.

 

[Scott06]

Update - Weather has been crap and work keeps getting in the way but I'm back on the investigation. Thought I would start with the manifolds and risers and hopefully eliminate them as the issue since they are virtually brand new. I rigged up a manifold and a blocker plate and pressurized both of them. After chasing links in my rig and a couple of the factory installed end plugs both manifolds held around 20 psi for an hour. I did a quick check of the surfaces of the manifold and rise and they seem to be square. I have a straight edge, what should I be shooting for as far as a max clearance? Tomorrow was going to focus on the risers, since I can't pressure test them I was thinking of installing a blocking plate and gasket and filling the cooling passage with acetone as I have read in other posts. Also, if the weather cooperates I hope to pressurize the cooling system tomorrow now that I have scabbed together a pressure manifold.

Tpenfield, the same cam was used for the rebuild, it was still in spec and good shape. Thanks for all the great advice and tips. More to follow, posted some pics of the pressure test.

There really shouldn’t be any warpage on the manifold to elbow sealing surface. If you see daylight under a it I would file them or have a machine shops mill them flat.

When u pressure test the cooling system be interested to see if u have an intake gasket leak or pinhole under the thermostat

 

[Lou C]

I think I've seen less than .003" listed in Volvo's instructions, not sure what Merc says. My Barr set were less than that, barely .001"

 

[AMMO DAWG]

Update 2 - Rigged up a plate to go over the thermostat housing and plugged the water pump hose with a piece of PVC with an end cap and hose clamp. In the first picture I was being lazy and used some scrap aluminum plate I had as is. Had a slow leak and realized it was my plate leaking. Went back and contoured the plate to better match the thermostat housing opening and bolted it down and it held pressure for hours. All the water you see is all the soapy water I was spraying around looking for leakers. So, I have to assume I have no leaks in the intake or cooling passages.
Next, I sealed the risers and filled the water portion with acetone for a few hours with no noticeable change in the level of the acetone and the exhaust section looked dry.
I did stumble on something while working on the intake, I brushed the oil fill and it fell off, looks like the locking porting that clamps it firmly in the valve cover is all cracked keeping it from sealing.
Well, last couple checks I have is flatness of the exhaust manifolds and risers and possibly a leak down test. Like to hear your thoughts, thanks.

 

[AMMO DAWG]

Update 3 - I did a check of the Manifold and Riser mating surface with a .002 feeler gauge and couldn't slip it under my straight edge. Can't find a smoking gun, starting to think somehow rain got in from the top which doesn't make sense either unless if got through the breather somehow? Stumped. Leaning toward putting it back together and running it and flush the oil a few times and see if I get any water in the oil.

 

[Scott06]

Update 3 - I did a check of the Manifold and Riser mating surface with a .002 feeler gauge and couldn't slip it under my straight edge. Can't find a smoking gun, starting to think somehow rain got in from the top which doesn't make sense either unless if got through the breather somehow? Stumped. Leaning toward putting it back together and running it and flush the oil a few times and see if I get any water in the oil.

It would seem you have eliminated all engine issues so must have come in through the carb. Not sure if your sunpad has a seam over carb or not. Do you have a flame arrestor cover on it ? These are intended to keep water out of the carb and distributor.they get on the way so people toss them

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[AMMO DAWG]

No. I do not have a cover, I bought the coat used and it didn't have one. I'll be on the lookout for one to add, thanks.

 

[tank1949]

I have a 2006 Sea Ray 185 Sport that I have been repowering from a 3.0 to a 4.3 and have an issue I just can't seem to resolve. Awhile back I found a donor 4.3 and outdrive and had the engine rebuilt at a machine shop I have used in the past. I purchased a set of aftermarket exhaust manifolds (not dry type) and risers and ran it on the hose to try and dial everything in. I went to check the oil one day and it was milky white. I also noticed it was dripping oil at the timing chain cover so I pulled the engine and returned it to the machine shop thinking I had an issue with a head gasket or worse. I watched the old boy who owns the machine shop tear it down reassemble the engine, do a blow down check on every cylinder and pressure check the cooling system, all was good. I also pressure checked the manifold, and they held pressure.

Fast forward after putting the engine back in the boat, ran it a bit and came out the other day and milky oil. I drained the oil and was surprised at the amount of water that came out prior to the any oil. Pulled the port riser and there was water as I looked down in the exhaust portion. Pulled the starboard side and no water, however when I pulled the exhaust manifolds and plugs water came out of all cylinders on both sides.

So, I don't know where to go from here. Is it possible that the manifold/risers are letting the water in the cylinders? I was going to pressure check the system one more time and leaning toward pulling the heads to make sure I get all the water out of the cylinders. We had some crazy rain storms, however the breather was on and the sundeck closed so I can't imagine rain water getting in. Not sure where to go from here, think the engine is salvable if I can get the water out? Thanks in advance.

do acetone test on riser and manifold. You may have an internal leak.

 

[AMMO DAWG]

I did a pressure test on the manifold and acetone on the riser, not leaks found ( check previous photos)

 

[nola mike]

This is the most thorough investigation that I've seen in a while. If it leaks again, that's your sign to scuttle the boat.

 

[AMMO DAWG]

The thought has crossed my mind, I'll let all know how it turns out!