It appears I have coolant mixing into my oil. When I've pulled the dipstick the last few times, it seems I have a chocolate milkshake in there. I'm borrowing a compression tester from a friend tomorrow to see how that looks. It has never heated as far as I have owned it (1 year) and only noticed it a month or two ago.

What else could it be other than a head gasket? Oil cooler leaking? (but that would apparently more likely present itself as oil in the coolant due to the pressure differential)

Could it be related to the thermostat or the housing? Any ideas or likely reasons here?

Thanks guys!

 

Does it look like this?



Could be the cold weather. Don't know where you are located.

 

Does the MINI run okay? Are you loosing antifreeze?

 

Let's see....
Cracked block....in the right place....
Cracked head...in the "RIGHT place"
But I would look at the oil cooler.....might be a simple fix!! Remember...when you turn off your motor, oil psi goes to zero, but the cooling system is pressured.... So coolant can seep in...
But STOP DRIVING IT....COOLANT IS A TERRIBLE LUBE......can DESTROY A MOTOR....

 

It could very well be like that image posted cerenkov. I'm located in NY and yeah, it's been a cold winter so far. Now I understand better what a catch can is supposed to do...

The MINI has been running fine. It just surprised me is all since I had only changed the oil 1500k ago. However, what prompted all of this was the coolant. It's never been full as long as I've owned the car but when I bought it, it had a leaking tank. The goal was to do a full flush on it along with a lot of other work (sc oil, hoses, etc) so I didn't want to go through it all and overlook what could be a more serious problem and have to do overlapping work if it was related to a head gasket.

I guess at this point I'll check the compression and report back. If it's healthy, I'll go ahead and do the work I wanted to do including flushing the cooling system and then monitoring the level once I know it's bled and steady. So there may be hope after all that it's just condensation?

 

Oh and good point about the PSI at the oil cooler ZippyNH. Anything I should know about checking/replacing seals and stuff on it besides letting the engine/cooling system cool down and maybe opening the reservoir cap to depressurize the system? I'm going to peel through the Bentley right now.

 

I thought the same thing when I saw the milkie stuff!



Drained the oil and all looks well!


Let us know how the compression goes of course, but the best test is to drain/change fluids like you're already planning to.

 

If compression comes out good, maybe I'll just send the oil off to Blackstone for testing. I had been planning on doing it at some point soon regardless. Then I'll know for certain whether it's condensation or coolant. Thanks for the pictures/affirmation Fir3Chi3f.

 

There have been random posts on cracked heat exchanger or cooler. Not too difficult. Just make sure to flush both oil & coolant out. Hope it's this & not the head gasket.

 

I was bleary eyed and looking at those sort of posts last night. What didn't seem clear is whether or not a set of gaskets for it might help the problem or if that only stops oil from leaking out of it.

 

If it's the heat exchanger, NO, a set of O-rings won't fix it. Ususally, it's the heat exchanger itself that's fractured or cracked. Those 2 O-rings will cure a heat exchanger oil leak only.

 

I was pretty certain that was the case as I brew my own beer and I'm familiar with heat exchangers in the homebrew world. So it's oil from the back, water from the front. I'll def consider it if I show coolant in the oil and compression is ok. Any other thoughts if it's not a HG, cracked head, cracked block or that? (I'm really hoping it's that)

 

I hope it's just the exchanger. I've seen how a cracked 1 made mayo really bad over at minitorque. The difficult part is the total mayo extraction.

 

I saw that one! Scary!! Should be early enough for me as I've only JUST started noticing it and my oil leaks like sieve so I'm always checking it.

 

Here's a milder case:
http://www.minitorque.com/forum/f24/...57/index2.html

 

Not sure if it might have contributed to it...but have you been doing coolant flushes every 36-48 months?
Failures, things from head-gaskets to radiators, to heating cores have become commonplace....the common thread....Failure to do BASIC maintenance!!
I sometimes find it amazing how much work folks will do to change a bushing, change oil EARLY, and do assorted other work...but never touch the cooling system...an item that when neglected can cost big $$$.
Hopefully ANYBODY reading these threads, that have an UNKNOWN time since their last coolant flush, will do one come spring....
It only cost you about $20 and an hour or so worth of time.....


a pic of a heatexchanger that has had an issue...from the above mentioned thread...
heater cores get plugged too.....with rust from the block as it corrodes.....

 

I actually have a ridiculously detailed history of the car. The guy I bought it from had all the work done at the dealer, kept all the papers, AND had the extended warranty which had expired about a year or less before I bought it from him. That said, coolant is probably one of the oldest fluids at 3.5 years I think so it's definitely next on the list.

I'll have to share the history with you guys at some point. It's in an excel spreadsheet and I think someone might appreciate looking at it. I can't imagine how much he paid (or would have paid without the extended warranty).

 

I believe that heat exchanger in the above pic is beyond just corrosion. It looks like it has let oil into the cooling system via an internal crack or fracture. Seen much worse where entire cooling system was clogged w/ mayo from a failed exchanger. As Zippy said, coolant flushes are easy & cheap best done every coupla years.

 

Most likely the oil cooler leaking attached to the oil filter housing if it is not the head gasket. Feel free to call with questions.
Ferney's Lube and Auto Repair - 303.762.9516

 

Thanks guys. Going to grab the comp tester now

 

Yes the oil cooler is the most common cause of the oil coolant mixing. We have to keep them in stock now.

 

Good compression! Guess who will be taking the oil cooler out :D Easiest to get to from the wheel arch, right?

Thanks for all the help guys. I'll keep you updated.

And attached is a picture of the dipstick.

 

Please do so! You've got me worried now that I've misdiagnosed the milky stuff.

My cap and dipstick still look pretty clean. If it is the heat exchange please take a picture!

 

BTW, my cap looked fine. Had a check engine light after comp test but that went away today. Possibly from too much fuel as I didn't pull any fuel pump fuses or press down the gas pedal all the way (not sure if this works to tell the ECU not to pump fuel in these cars).

Note: Although I wasn't looking very hard, I didn't notice any coolant in my oil on the last change which was about 1500 miles before I caught it. I'm sure I still have it around but the oil catch pan lives outside so I'm sure it was contaminated with water before the change :/ .

 

+1 on the oil cooler.



Here is a thread with the diagram and seals for the oil cooler. And I shot of it through the wheel well.

https://www.northamericanmotoring.co...this-part.html

Here is a another shot of it.

https://www.northamericanmotoring.co...il-cooler.html

Hope you can get that fixed and resolves the problem. Make sure to change that oil/ oil filter a couple times to try to get that residue coolant out.

Thanks