Milky oil, knocking sound, and excessive water in exhaust

[Dallas J]

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Motor: 4g64 7 bolt bored 0.020". Eagle, wiseco, Mitsu bearings, 1g head....etc.

So this is with about 5-10 minutes of idling on this oil. I pulled the pan to check the rod bearings and everything is fine there. You can see the milky oil just starting to pool by the turbo drain line. Cant for the life of me see where it would have come from though.

Other symptoms are a knocking sound developed within 5 miles of parking it. When I start the motor cold it doesn't knock, the knock starts about 1 min after start-up. Lots of water coming out the exhaust. If I free rev it I can get nearly a vapor cloud.

The car does have a tendency to loose coolant and oil, but those are pre-existing conditions and I think separate. I think the coolant cap isn't holding pressure, and my valve seals are bad as can be seen by my piston conditions considering only 8k and E85

Anyone seen anything like this or have ideas?

The head gasket looks perfect, plus a head gasket wouldnt cause knocking a minute after startup.

Cracked cylinder wall to the coolant jacket? I dont know how this would cause the knocking though.

Could their be a crack in the coolant jacked on the oil filter housing that only gets coolant to the oil going to the turbo?

 

[Cassera]

A bad head gasket could cause Coolant and oil to mix causing the milky oil that you see.
Also check the head, because usually when you have a bad head gasket it can cause a Head to warp......Try doing a leak down test.

 

[Dallas J]

The engine is out of the car and head is on the bench (so no leak down testing). The gasket doesn't show any signs of failing its composite and all the composite failures I've seen were somewhat obvious.

 

[Cassera]

Hmmm, If you are sure that the head gasket is fine than I would check the intake gasket.
Also, Water + Oil results in bearing failure.

 

[Dallas J]

Hmm, not sure how an intake gasket would have anything to do with coolant getting to the oil pan...

Forgot to add I did both a cold and hot compression test, both were 175-185psi in all cylinders. I did cold and warm because it didnt knock when it was cold, but did after running a minute...No change in the numbers.

 

[Cassera]

Hmm, not sure how an intake gasket would have anything to do with coolant getting to the oil pan...

Forgot to add I did both a cold and hot compression test, both were 175-185psi in all cylinders. I did cold and warm because it didnt knock when it was cold, but did after running a minute...No change in the numbers.

Wow, thats really good compression......

Yeah, true...that wouldn't explain why coolant is mixing with your oil...

Im stumped....How could you have perfect compression in all cylinders but have coolant in your oil pan? How is that coolant getting inside your oil pan?

Maybe somebody else can chime in.... Im sorry but Im stumped

If I can think of anything, I'll be sure to post....

 

[Dallas J]

Compression should be in this range with a 2.4l and 9:1 compression. How the oil is getting in the pan is whats got me stumped too. I can see it coming from anywhere and its completely localized to this one spot.

The small bit you can see in the engine can be explained by it draining while the engine was upside down to remove the pan, which only took about 3 min.

Im really leaning towards it coming from the turbo drain, but would it be coming from before the turbo or a cracked jacket in the turbo.

 

[pj91gsx]

is your turbo center section cracked? make sure your balance shafts are eliminated properly. check to make sure bolt oil holes are blocked off, on the balance shaft that is oil feed by the block.

 

[Dallas J]

The balance shaft oil holes are all blocked off properly. Used the actual mitsu tool to install them clocked away from the oil hole.

Remember, the engine had no problems for about 8k miles, then went to lunch one day and it started knocking on the way back. I dont even remember if I got on it, probably not with traffic.

 

[dented_coffee]

turbo failure. coolant threw oil return tube and clearly visable by the oil pan, exessive water in the exaust. water is thinner that oil so if there is a crack in the center cartrige on the turbo the water will flow to where oil is used to lube the bearings and is getting pushed out the exhaust.

water getting into the oil cavern of the turbo getting pushed into the exhaust/and oile drain tube. maybe the turbo started to seize and got hot and cracked, maybe the coolant cavern of the turbo got clogged or a kinked water line causing it to crack and then water to flow back into the oil.

my money is on the turbo. do a tear down and inspection on it.

 

[JacksonAuto]

Could be the turbo, head gasket, cracked block or cracked head. It's only knocking when it's warm because the temperature causes the clearances to open up. It wont knock when it's cold but once everything warms up and grows it starts knocking. It's hard to tell from the pic you posted but it looks like I see bearing material in the pan ( the copper looking stuff opposite the turbo drain ).

Did you pressure test the cooling system before you took the engine out? If not, once you get the engine apart you can have the block magnafluxed to see if it's cracked.

Is the engine still together? Even if it's out of the car you can do a leakdown test if the rods, pistons and head haven't been removed. A leakdown test will tell you where the coolant is coming from.

Was the head pressure tested before installation? You should remove it from the block if you haven't already and take it to a machine shop to have it pressure tested and also check to make sure the deck is flat.



As a side note, look closely at the block. We've had a lot of the 2.4 blocks come through the shop that have very thin cylinder walls. Unlike the 4G63T blocks, they weren't designed to handle boost. This is why we sonic test all of the blocks. If you had a thin spot to start with, then punched it to +.020" that could be your problem.

 

[Dallas J]

Theirs no visible bearing material in the pan or oil (just checking looking at a thin layer in the sun for anything reflective/shiny). Their is a bit of RTV from a hasty cleanup to put the pan back on, also used the wrong (non-high temp) RTV just cause I knew it was all coming apart again after running for a few more minutes.

I didnt pressure test the coolant system, although I should have. Today Ill pull of the crank to double check all the bearings, but the rod bearings looked great when I pulled them off last week.

Im gonna take the head somewhere to get checked out since that's sort of an unknown for me. I got it from a friend, but the valve seals leak pretty bad so Im not so sure about it.

I can say that this all happened after turning the boost back up for the summer. I run E85 during the summer and generally have it at 22-24psi. This year though it seemed the turbo didn't want to hold as much boost as usual, falling down to 21psi by redline.

How would I go about checking the turbo center? Somehow pressurizing the water section and checking for leaks? Not sure how I would go about doing that...

 

[1995gsx20g]

what about your oil cooler? factory sandwich plates mixing coolant and oil together?

how is your crankcase breather setup?

 

[Cassera]

Be sure to keep us updated!! I am very curious to see what that knocking sound was

 

[PieEyedPiper]

How would I go about checking the turbo center? Somehow pressurizing the water section and checking for leaks? Not sure how I would go about doing that...

I might just go for a visual inspection, pull it off, pull it apart and go from there. It likely needs a rebuild anyhow with water in the oil. Just something to think about. Ask Justin about water+turbo+bearings maybe.

 

[BoostFrenzy]

what about your oil cooler? factory sandwich plates mixing coolant and oil together?

My vote goes to the sandwich plate (if you are still running that style) and could explain the symptoms of turbo failure if the turbo is fed from the OFH.

If you really suspect the turbo, you can run the 16g without the coolant lines (loop the block side lines and cap the turbo side) for a bit and see if the problem still persists. If it does you know to look elsewhere. If it doesn't, then also check the capped turbo coolant lines for oil as that would indicate a crack somewhere inside the CHRA is letting it leak into the coolant system.

 

[Dallas J]

The only problem I have with the factory oil cooler (which I am running) is why would it only go to the turbo? As of right now I have only found the water/oil mixture in the pan at the location shown with no signs anywhere else.

Could the coolant jacket have cracked enough to get coolant to both the exhaust and the oil? And would this crack cause audible noise at idle without screaming at full boost? Well, caveat...I dont think I ever got into + pressure after the noise started, but I did drive it home and under load it would have spun up a bit.

Ill update tonight with proper pictures after I pull more stuff apart.

Latest checks...

Pulled the Girdle, all bearing look perfect.

Pulled front case, oil pump shows no signs of wear.

Catch can was kinda full... could have sucked up some sludge, not sure I buy it so much though.

Tomorrow Im gonna strip the head down to replace the valve seals and I guess start putting it back together. I cant find anything wrong with the bottom end. If it was a cracked cylinder, then I doubt I would get the compression I am both warm and cold.

 

[JacksonAuto]

I cant find anything wrong with the bottom end. If it was a cracked cylinder, then I doubt I would get the compression I am both warm and cold.

A cracked cylinder usually wont show low compression during a cranking compression test. It *may* show up on a leakdown test. The only way to know for sure is to magnaflux the block or pressure test the cooling system. Also, if the crack is below the piston's travel it will not leak compression. A compression test is an invaluable procedure but it cannot diagnose everything.

Where was the knocking noise coming from?

 

[1995gsx20g]

what bothers me about all of this is that water is not totally mixed in with the oil like a classic head gasket. why so little water only coming from the area of the turbo drain WTF i keep thinking of conditions that could create this but come up with nothing so far..

 

[Dallas J]

It was really hard to confirm where the knocking sound was coming from. You can hear it best under the car around the 4th cyl/turbo/transmission area. Using a screw driver as a stethoscope I listened to the oil pan and bell housing but couldnt hear anything matching the knocking noise.

The knocking didnt change with the clutch in and in gear or not.

what bothers me about all of this is that water is not totally mixed in with the oil like a classic head gasket. why so little water only coming from the area of the turbo drain WTF i keep thinking of conditions that could create this but come up with nothing so far..

Thats exactly whats confusing me...Its just so localized.

 

[1995gsx20g]

in your oil pan in the pic above is that speedy dry that looks like chocolate crunchies found in carvel icecream cakes?

you never did mention what your oil pressure is while warm and while cold, what was it?

keep in mind that pressure goes from high to low(during normal operating conditions oil pressure should always be higher than coolant pressure.)

about your catchcan setup, do you have a working pcv that is plumbed to the intake mani?

im not trying to call you out because situations do arise where things cant always get done the properly but i am curious on how this can happen so.. why did the motor have only 8k on it and have pre-existing coolant and oil leaking problems?


are you sure it was a metal to metal knocking noise?

on my own car i have a water leak that drips right from the upper most left stud for my exhaust manifold. only drips about 15 drops while cold then stops once it warms up a little. i haven't had time to investigate yet but they may be related.

 

[Dallas J]

you never did mention what your oil pressure is while warm and while cold, what was it? keep in mind that pressure goes from high to low(during normal operating conditions oil pressure should always be higher than coolant pressure.)

Oil pressure gauge sits in the middle of sweep at idle and moves up to about 3/4 through the rev range. Since I dont have the balance shafts I have the oil bleed valve ported. Pressure has been the same since the oil pump was new (when I built the 2.4).

about your catchcan setup, do you have a working pcv that is plumbed to the intake mani?

I had one line running from the valve cover to a vented catch can since about 50k miles (now at 103k), and about 2k miles ago welded a fitting to my intake manifold to run that line from the valve cover through the catch can then to the intake pipe. Although, the catch can is hollow and should have at least something like steel wool to prevent oil from getting straight through. Its on my to-do list . and I do see some oil blowing through to the turbo inlet.

The PVC valve has always been hooked up to the valve cover. Recently I replaced the PVC valve cause it was leaking when pressure testing. Also the line going from the manifold to PVC valve was old and spongy so that got replaced too.

im not trying to call you out because situations do arise where things cant always get done the properly but i am curious on how this can happen so.. why did the motor have only 8k on it and have pre-existing coolant and oil leaking problems?

The car had no external leaks other than the slip yoke at the T-case (which I replaced last week). I do seem to have a bit of problem loosing coolant and oil with no signs. I think the coolant lost is because my cap is going bad, but Im going to put the car back together and pressure test the coolant to double check. Oil loss im pretty sure is from the valve seals. They are pretty bad, bad enough that I have significant carbon on my pistons and valves even with E85 which keeps my buddies pistons very clean.

are you sure it was a metal to metal knocking noise?

At this point im not sure of anything. Hell, it could be a collapsed lifter that was just easier to hear under the car where the rest of the clatter is blocked. Their are no signs of mechanical wear anywhere.

Monday the head is going in to get pressure tested, hot tanked, decked, and new valve seals installed. If all looks good with that Im going to start re-assembling everything with new gaskets and new lifters to the point where I can pressure test the coolant and the cylinders. If that looks good then its going back in the car hopefully in time for my next points autocross.

 

[donniekak]

With The thin walls of a 4g64 punched out, combined with the crappy rod angle of the 100mm stroke, i wouldn't be surpriseed if your block was cracked. Have it magnafluxed. What was your ptw clearance?

 

[1995gsx20g]

what was your gut feeling of the noise? as stated b4 don't rule out the block being cracked. im just concentrating on other areas because it either is or isn't cracked and there is nothing i can do to help about that.