Oil cooler seals question

Mericet · Mericet's Garage

How long should these last?

I have a receipt that shows that these were done in 2008 on my car (by a PO) at 92K. There is now 110K on the car and I am replacing the radiator. I noticed some black deposits in the overflow tank as I was draining the coolant. No milkshake, but it did turn milky when I added water to the tank and shook it up. Just did an oil change and there was no trace of water in the oil either.

Guess I will have to do a pressure test to make sure all is fine.

John_AZ · 05-21-2011, 05:04 AM

Can fail at any time if the PO or shop did not pre oil the 2 big green "O" rings on the oil cooler inside the cooler housing-the seals can "roll" or deform. Or severe engine overheating. Just a matter of time.

A pressure test may not show up oil cooler housing seal failure. It will pinpoint drips on the outside of the engine.

I would do a leak down test to see of the HG may be leaking. A leak down test will show bubbles in the expansion tank if the HG is bad.

Compression-leakdown test

GL
John

Mericet · Mericet's Garage

Thanks John. It seems the place that did the work is a reputable shop. There is no indications that the car ever ran hot and it certainly has not since I purchased it. I will do a leak down test to make sure there is no issues.

89-944NA · 89-944NA's Garage

The shop that did the reseal may not have cleaned out the tank (have seen that many times).

Mericet · Mericet's Garage

Quote:

Originally Posted by 89-944NA

The shop that did the reseal may not have cleaned out the tank (have seen that many times).

I had thought of that but can remember the tank being a lot cleaner. It actually became difficult to see the level of coolant in the tank. I know the car also got fresh coolant at about 93K when I purchased the car and did the belts and water pump. Could it be that the system was not cleaned properly and I am just starting to see that effects of that?

89-944NA · 89-944NA's Garage

Are you losing coolant? It is possible that it is crud left in the cooling system from before, slimey nasty stuff does accumulate in the cooling system if it is not flushed on a fairly regular basis. Like John said, do a leak down test before you start tearing into it.

Mericet · Mericet's Garage

I was loosing coolant which is why I am replacing the radiator. It was during the installation of the new radiator that I noticed the overflow tank was really nasty. I have re-installed the radiator, will flush the system and then do a leak down test.