Coolant in my engine oil

[PJ Grady Inc.]

OK, I'm a little late to the party, but here is some advice I found elsewhere, and perhaps it will be useful to the next person who has this kind of engine trouble.

If you get the cylinder at TDC compression stroke and put air in it, there are a couple of things you can do, assuming your valves are properly adjusted. If you have a compression tester, remove the Schrader valve in the bottom of the tube that screws into the spark plug socket. Now you can put shop air into the cylinder. Once you have air flowing into the cylinder, there are three tests that you can do.


1. take the radiator cap off and look for bubbles. Bubbles could indicate a blown head gasket or warped/cracked head.

2. listen for air escaping out the oil dipstick. Air escaping here could indicate leakage past the rings.

3. listen for air escaping out the tail pipe. Air escaping here could indicate a leaky exhaust valve.


Kind of old school diagnostics, but might give you an idea of what to look for. I'm sure there's probably more to it, but that's all I can remember right now.

Remember, I am not a mechanic.

These procedures you describe are for the use of a "Leakdown tester" which is much better than a compression tester. We use it in the shop to measure the amount of air excaping from the cylinder. More than 15% leakdown indicates a problem. Occasionally the leakdown is bad enough (over 20%) that your three listed steps can help pinpoint the cause of the leakage. A new broken in PVR engine usually has about a 3 or 4% leakdown rate.
rob

[SS Spoiler]

Thanks for the ideas. I will dive into it this fall after I win a few more trophies....ha

[Farrar]

These procedures you describe are for the use of a "Leakdown tester" which is much better than a compression tester.

I don't have a leak-down tester, but I have perfect hearing (at least according to the U.S. Air Force).

[David T]

I was just guessing on the pressure reading off the dash gauge.
The blow-by is bad enough to pop the oil fill cap off. My milage has dropped
about a third and power is weak. It's crazy but it starts and runs well. Oil
is clean, smokes a little. Looks like an engine build this winter. Now the question
is keep the turbo and add forged pistons, or toss the turbo and go for cams and
headers. What's the best way to go? Meanwhile got a car show coming up.
Took another first place last week. Sometimes it's nice being the only DeLorean
in town.

Paul/Kate Cerny
# 2691 Kalispell, MT

If you have a turbo and you keep popping the oil filler off and blowing out oil, you overboosted and damaged pistons. Yes, you can do all kinds of testing but why? You already know you have damaged pistons and have to take the motor all apart. It is either that or get another motor.

[121GWATT]

Ok, so lets get this thread back on the original topic.
I pressurized the coolant system, but was unable to find any exterior leaks. But I removed the intake manifold I most definitely found out where all my coolant has been going (see photo)! F***! Not sure how long this has been happening. I cleaned up most of the coolant pooling. Still haven't found the source of the leak. Further investigation will have to wait for a couple days due to my schedule.

IMG_2909.jpg

[Riley88]

I don't have a leak-down tester, but I have perfect hearing (at least according to the U.S. Air Force).

I died laughing. Navy here, couldn't it be more true? YOUR HEARING IS FINE DAMMIT!

[DMCMW Dave]

Ok, so lets get this thread back on the original topic.
I pressurized the coolant system, but was unable to find any exterior leaks. But I removed the intake manifold I most definitely found out where all my coolant has been going (see photo)! F***! Not sure how long this has been happening. I cleaned up most of the coolant pooling. Still haven't found the source of the leak. Further investigation will have to wait for a couple days due to my schedule.

Drain the oil, and then pressurize the cooling system again with the drain plug out. That will show any internal leaks, i.e. cylinder jugs or certain forms of head gasket failure.

The valley leak is probably the hoses. There are quite a few connections that will dump into that area.

[DMC5180]

Judging from the green residue at each end of Y-pipe connection, it would be a strong indicator of leakage.

[David T]

Once you find leakage under the intake manifold it really doesn't matter what is leaking, you are going to redo ALL of the hoses, gaskets, and seals under there.

[DMC-81]

Once you find leakage under the intake manifold it really doesn't matter what is leaking, you are going to redo ALL of the hoses, gaskets, and seals under there.

+1.

It's also a great opportunity to clean the carbon out of your intake ports and manifold. I used cotton shop rags, and spray cans of carburetor cleaner. A one-foot piece of small wooden dowel helps reach the inaccessible areas with the rag. When cleaning the ports, to avoid having the cleaner wash down the cylinders, I sprayed the cleaner on the rag, not into the ports, (unless of course you can turn the crank to close the valves).