engine and drivetrain I Think I Really Pooped The Bed This Time

[devotion]

Long story short, the electric fan I have on my 76 is not hooked up. It has been 25* here since I got the car running after sitting for 5+ years...so no problems overheating...until today. I started the car to warm it up, and totally forgot about it for 10-15 minutes.  When I remembered it was running, there was coolant all over the ground, and the temp gauge was pegged in the red zone. Let it cool down for a half hour, checked the coolant, added water.  Checked the oil, and the oil still looks good, as well as the coolant in the radiator.  Got the car started and ran like a champ all the way home. No overheating, no loss of power (didnt drive it hard, but pulled as strong as ever, no new sounds etc). Let it sit for a few hours and went and checked coolant again. Sure enough, oil in the coolant. Not a milkshake, but cloudy with tiny specks of oil floating on top of the fluid in radiator. What all have I done would you guess? Oil still looks good on the dip stick. Thanks for all the advice in advance!

 

 

[colorobo2002]

Doesn't look good. And your car can run somewhat ok with a leaking head gasket. Do a compression test, two adjacent cylinders with low compression are a likely indicator. Search on the FAQ for compression test and blown head gasket and you'll get a bunch of good info.

[Chamonix72]

I see...in your future...a compression and/or leak down test....a trip to a machine shop to make sure your head isn't warped...

[devotion]

I dont suppose there is a way to test for head warpage without taking it off first? Because that would be really really cool

Oh, and if the head IS warped...what is a guy to do about that?

[Chamonix72]

Nope. Head's got to come off. If it's warped, your machine shop can may be able to sort that out for you. Perhaps it can be straightened and/or planed smooth. 

[devotion]

If the head is warped, and can not be planed smooth, is there a source for a "new" head?

[Chamonix72]

I don't think so. Time to get a core head and have it made as-new.

[Harv]

I think BMW still sells new heads, no? I know they sell new S14 blocks and stuff.

I'm sure it's your head gasket. Take off head. Bring to machine shop with the upper timing cover and ask them to check and skim if required. Put back together using your original head bolts.

John

[Hans]

Best to get the head checked while its off. But I'd be concerned about other damage to block.

[Mike Self]

A final Hail Mary trick before you pull the head.  

 

If the low compression is in your two center cylinders (2 & 3), it may (emphasize "may") be a warped head vs blown head gasket.  A head will bow in the center when it warps, so if your low cylinders are 1 & 2 or 3 & 4, this probably won't work as it's most likely a blown gasket vs warped head. 

 

Try this:  retorque the head using the normal torquing pattern by slightly loosening each head bolt in turn and then re-torquing in sequence.  Then do a compression test to see if the two center cylinders' compression has come up.  Finally road test and see if you still have coolant and oil mixing.  If the compression in the two middle cylinders is now comparable to 1 & 4, and there's no more coolant/oil mixing, you may have re-seated the head.  But keep an eye on things to make sure you actually cured the problem.

 

Good luck

mike

Edited January 31, 2014 by mike

[devotion]

ok, did a compression check. Here are the numbers.

 

cylinder 1

60-90-100-100

cylinder 2

30-70-80-90

cylinder 3

60-80-90-90

cylinder 4

40-60-60-65

 

Does this mean anything to anyone? Seems like they are all over the place.  The tester I used was tricky to get in the plug holes, and when they did go in, impossible to tighten down past finger tight...I know youre not suposed to torque them down, but I was worried pressure may have been sneaking past the fitting

[roadhog0]

Looks like your bottom end is about as worn out as mine was... I had about 100psi on all cylinders. Looks like you probably popped the gasket somewhere around cylinder 4...