Scroff

Fully rebuilt my 22re a couple weeks ago, has ran fine for 100-150 miles, now develloped a horrible noise coming from the valve cover... so I checked it and sure enough the oil is watered down and not lubricating as it should. Happened 20 miles after adjusting valve lash ( a little tighter than spec to attempt to quiet the velve chatter) Funny thing is though... no oil in the coolant, no steam out the tail pipe, and still was running perfectly. I assume its a head gasket, but is there a way I can check before I tear into this pile again?

Scroff

Also, I put a brand new head on it, so I dont think it is warped or cracked.

iamsuperbleeder

yeah, quite possibly a head gasket, in one of those area's that a compression test wont show thow... it would be leaking into a spot where the water's under pressure and the oil isn't...

I'm assuming your also losing a good bit of coolant?

Scroff

Actually no, no noticeable coolant loss, just frothy oil.

abecedarian

hit me in a tender spot...
my 91 did something similar... one day running fine, next... crankcase full of coolant.

the most likely culprit is the front timing cover, it's seals and gaskets. The timing chain runs dangerously close to the water pump, and if the guides are broke, the chain can wear into the water pump housing and cause the coolant to drain into the oil pan.

abecedarian

actually, the oil only passes through the head gasket in two places: to the front of the engine on the intake side, near the chain, the supply passage to the rockers/etc., and at the rear of the head on the intake side is a return to the pan.
So it's unlikely the head gasket will fail in either of those spots into a coolant passage- they are actually quite far removed from cooolant passages.

Scroff

I checked the cover on rebuild, and added steel guides, im almost positive the chain did not wear through. since the rebuild.

abecedarian

that does not mean the cover didn't leak "internally".

there are serveral places in the cover that have the potential to leak coolant into the crankcase.

Scroff

So you think the head gasket is alright and pulling the pan, cleaning everything out, and replacing all the gaskets on the timing cover, oil pump, etc would be my best course of action?

abecedarian

I am dealing with the same problem on one of my trucks, and have decided to replace the engine entirely instead of spending time tracking down something I may not find. my likely culprits are the timing cover, a crack in the head and a crack in the block.

abecedarian

I pulled the head and found no evidence of a faulted head gasket... found no evidence of an intake manifold leak....
and the fact the engine failed suddely, leads me to believe that even if the head gasket or intake were at fault, there's no way 100% of the coolant could have contaminated the oil within one minute. That is a "gross" failure... which would mean something around the water pump failed... in my opinion.

abecedarian

I don't think something as simple as that will fix the problem.
Rather, pressurizing the systems, leakdown in the cylinders, pressurizing the radiator, and looking for failures may be a better start.

Scroff

Wouldnt a gross failure A) completely drain my coolant or B) Mix oil in the coolant as well as vice versa. My oil does not look super saturated with coolant yet, just obvious that there is some in it. Also, I had the block pressure tested a week ago.

abecedarian

a) Depends on the gross failure... if it's a 'simple' gasket failure around the water pump area for instance, the coolant will likely only migrate into the crankcase in order to make the same fluid level in the cooling system and the crankcase.
b) if where the failure is, there's more pressure in the cooling system than there is in the oil system, the coolant will migrate into the oil, but not the other way around.

Scroff

UPDATE.. Alright, So I drained the oil entirely and added a fluorescant dye to the coolant.... on running the engine for half an hour with new oil, i still have somewhat murky oil, but there is absolutely no coolant in it. (ran the oil under a black light) So I guess I was wrong on the coolant part. Any other ideas what else could be causing this? Maybe just residual water that may have gotten in there on the rebuild? Think it is safe to drive it?

Scroff

Also did a compression and leakdown test and all tested good... so Im just confused, the oil is not as white or frothy as other coolant filled oil I have seen, but more like a dark chocolate look. I have heard this can be from straight water, but I am confused where this could be coming from/ came from.

annoyingrob

try changing the oil a few times. could have been something residual in the oil passages.