Oil in my coolant system. 1HDT needs help. Why is this happening?

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Hey all. I've been getting a bit of oil in my coolant system for a few months now. Had it flushed. Now there's more. Anyone seen this or had any experience with it? Kinda freaking me out...
 
Oil cooler perhaps. You need to get it sorted out ASAP though, I wouldn't continue driving it.
 
Yeah, first two things to look at are head gasket failure, or the oil cooler on the side of the block may be leaking.
 
Head/Head gasket failure doesn't seem common on the 1HD-## but it would pay to get one of those tester kits IMHO and see what result you get. If that's negative, X2 on Oil cooler.
 
There are some places in the timing gear cover that have oil on one side and coolant on the other.
 
If ther is oil in the coolant, check to see if there is coolant in the oil with a Blackstone test. My FZJ had a cracked head which took quite a bit of sleuthing by Robbie to find, but the first step was that test.

If water is in the oil, you need to get it sorted pretty quickly, as it is not good for the bearing surfaces.

As others said, I would first look at the oil cooler as the suspect. The turbo has both oil and water, and that could be another source of cross-contamination.
 
Are you sure it's engine oil and not trans fluid? I've never heard of it on an 80, but 3rd gen 4runner's have the rad/trans cooler fail and mix fluids, so that's another thing you might want to explore.
 
I've had oil in my cooling system.
Happened after i installed my Bad Boy (25 psi) thought i had some serious trouble with my low km 80.
Had remembered on another thread about external oil leaks around the head gasket and that some had had success with
re-torqueing the head bolts.
Figured i had nothing to loose so i gave it a try, flushed my system and then kept on driving.
Cleaned up a minor bit of residual oil that collected in the filler neck during the first few days but it has been at least 20000 kms and not a drop, speck or anything else to indicate that there is a problem.
I imagine that i just got lucky (rather be lucky than good any day!!!) but knock on wood....she seems good.
Maybe you'll get lucky too....
 
Chances are, this is bad. We saw this on two 1HDTs and one had internal cracks in the block that were not fixable, the other an crack in the head. Another occurrence on a 1HZ, where only the head gasket was bad.
The oil cooler is a possibility, but not likely. The turbo is definitely a possibility.
I no case it will be cheap and quick to fix.
The do-it-yourself tests designed to find exhaust gas in the coolant work really poorly on a diesel, as the fluorocarbons that are put in are fewer than in a gasser.
As Steve said, have a professional test of both, oil and coolant done (like Blackstone), that will tell you both ways (oil--->coolant and coolant--->oil).
 

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