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Oil in Antifreeze?

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AUSMHLY

AUSMHLY

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BJ8. I may have a leaking head gasket?

Today, engine cold, I removed the radiator cap, I see green antifreeze. I don't see the top of the radiator fins. I did when I changed the antifreeze 150 miles ago. Should I be able to see them? If not, does that mean I have oil in the antifreeze?

After a half-hour drive I see a lot of condensation under the radiator cap and valve cover. Not sure if it's water or antifreeze. Hard to tell by taste test. I've been told the engine isn't getting hot enough to burn off the condensation, but now I'm wondering if it is antifreeze being I can't see the fins in the radiator. Related?

Leaking head gasket allowing oil in antifreeze, antifreeze in oil?
Oil dip stick shows clean oil. Oil seems OK under rocker shaft. Not milky or thick.

What can I do to confirm if I have a leaking head gasket?
 

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When the engine is hot, is there a color to the exhaust?

Blue/Blackish- oil leaking past rings, or mixture too rich
Whitish- coolant (leaking head gasket - or worse)

Do all cylinders have approximately equal compression psi?

Tom M.
 
I agree with Tom, do a compression test. I also don't think a ½ hour drive would get everything hot enough to evaporate all condensation. When I was trying to confirm my head gasket was leaking, it was, I was driving for an hour at highway speed. Both my oil and water confirmed it was leaking.
 
When the engine is hot, is there a color to the exhaust?
Hard to tell, I'd say no.

Compression test cold 1)165, 2)165, 3)170, 4)170, 5)170, 6)180

Cold engine, when looking down the radiator neck, should I be able to see the fins? New Prestone coolant about 150 miles ago.
If not, good news. If I should, what could cause that?
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Seeing the fins is a shaky test for coolant/oil contamination.

Carefully loosen the drain plug on the crankcase. Coolant settles on the bottom, so if the first drips that come from loosening the plug are watery green ... there's your proof.

Let us know what you find. Your good compression readings are good news, but contamination could be due to a gasket tear.
Tom M.
 
If you have a coolant recovery tank, the radiator will always be near full, hot or cold, so you can't see the fins - if you don't have a coolant recovery tank, it will probably be at least 1 to 1.5 inches below the cap when cold, but will expand up to the cap when hot.
 
I don't have a recovery tank. Antifreeze is 1" below bottom of lip.

People who do not have any issues...Cold engine, when looking down the radiator neck, coolant level 1" below bottom of lip, do you see the fins?
 
What's that floating in your coolant; part of a test strip maybe? Coolant looks a little dark to me, and normal fill level is about an inch below bottom of the filler neck (more will just go out the overflow pipe). Oil in the coolant would be an iridescent film floating on top; I don't see any.

Condensation is one thing, but there appears to be a puddle of coolant under your rockers. It appears you have a coolant leak on the top end somewhere, but it doesn't appear to be a blown head gasket.
 
What's that floating in your coolant; part of a test strip maybe?
Bob, that's a reflection of overhead garage lights. Good eye!

Not sure why the coolant would be that dark. Engine was rebuilt about 300 miles ago. New Prestone/distilled water 50/50. 150 miles ago I drained Coolant out of radiator only and replaced 50/50. So some coolant was still in engine.

Bob, if not a head gasket issue, how would coolant leak on the top end? Would you elaborate how it gets there or what I can test or look for to find that issue?
 
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AUSMHLY said:
...
Bob, if not a head gasket issue, how would coolant leak on the top end? Would you elaborate how it gets there or what I can test or look for to find that issue?
Click to expand...

I have no idea. I've seen some oils that have a greenish tint, but that looks like coolant in the shot under your pushrods. Maybe a crack somewhere in a coolant passage; if so, your coolant level will go down over time. Prestone is almost fluorescent green; the stuff under your rocker looks about right, the stuff in the rad doesn't (but that could be gunk from the engine). I don't think it's 'condensation,' which would only be water. I think you have to take the car out and drive a hundred miles or so and see what happens (bring a cell phone and your credit card; maybe stay close to home).
 
Bugeyze said:
Hello, is this the same head as in previous post, CYLINDER HEAD RE-TORQUE?
Click to expand...
Yes

BJ8 Cylinder Head Re-Torque

Hello, I had the engine rebuilt about 10 months ago. I've put about 200 miles on it as I'm in the process of removing/installing the transmission trying to rebuild it. There is a copper-colored sealant oozing between the head and the block (photo attached). I keep wiping it off, but it keeps...
www.britishcarforum.com www.britishcarforum.com
 
Get a coolant system pressure tester. Pump it up to the pressure stamped on Your radiator cap and see if the system holds pressure.
 
Here’s what my BJ7 looks like. Has about 105,000 miles on it. Haven’t touched the coolant in about 5 years. Filled with 50/50 mix. Could your mix ratio be stronger than you think.
C570FC53-09F4-4F00-BB96-92707EB1BBBA.jpeg
 
bdcvg said:
Get a coolant system pressure tester. Pump it up to the pressure stamped on Your radiator cap and see if the system holds pressure.
Click to expand...
7psi for 50 minutes till it dropped to 6psi. Is that acceptable or it shouldn't lose any pressure.
 
Thanks Vette, 50/50 Prestone/distilled water.
According to your photo, I should see the fins. Being I can't could it be some residual rust in the engine block from when it was rebuilt 400 miles ago?
 
I have no expertise in this area. Your question about how long the system should hold the pressure seems a valid one . Hope someone has the answer.
 
If this is your only problem, then I don’t think you have oil communicating with your coolant.

One critical fact you have not mentioned: Could you see the fins before you removed the old antifreeze?

Antifreeze/coolant can be very dirty due to contaminants and rust in the water galleys. Your picture is not unusual.
 
QUIT GUESSING! Get yourself a combustion gas in coolant test kit, or stop by a local garage that has one.

www.mastercool.com

43707 COMBUSTION GAS LEAK TESTER KIT - My Website

Fast, economical and accurate method to test for combustion gas leaks from head gasket, cylinder head & engine block. Dual chamber for improved accuracy and to reduce the risk of coolant contaminating the test Works on gasoline & diesel engines Indicates that a leak is present when the tester...
www.mastercool.com www.mastercool.com

If you have a head gasket breach, this will be a clear indicator (tests for products of combustion in coolant).
 
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