How do you test the oil cooler?

[chevyaddict]

How do I test an oil cooler to see if there is some kind of breach inside it potentially causing water to get in my oil? Can these actually be tested? Do they fail and cause this to happen often? I highly doubt it but want to rule simple things out before going to gaskets and/or a potential cracked block or head. Yes, I have massive amounts of water in my oil but I replaced head and intake gaskets with top-of-the-line (proper) gaskets about 30,000 miles ago so doubt that is the problem.

 

[DonB]

There are a couple ways. One...It is a round about way, but using a Stant cooling system pressure tester pressurize the cooling system and notice the pressure bleed off. Remove the oil cooler from the system by by-passing it. Pressure test the cooling system and see if it still bleeds down.
Or you could rig up the pressure checker to connect to the cooling tubes and hoses for the cooler where they connect to the cooling system.
Another way would to put the cooler in a bucket of water and put air to it. If it is leaking you will see bubbles from the coils.

 

[chevyaddict]

Thanks... that is good to know. Someone messaged me and said its unlikely to be the oil cooler because there is more pressure in the oil system than the water system... which makes sense. I have a feeling this isn't my issue but it might be worth testing like you said so thanks!

 

[gmjunkie]

Thanks... that is good to know. Someone messaged me and said its unlikely to be the oil cooler because there is more pressure in the oil system than the water system... which makes sense. I have a feeling this isn't my issue but it might be worth testing like you said so thanks!

That would be correct!

 

[DonB]

Yes I agree that there is more pressure in the lube system than the cooling system. One thing to keep in mind though is...The lube system does NOT characteristically corrode from the inside out as does the cooling system. Just something to keep in mind.

The cooler itself is easy to remove. Remove 2 local hoses and the oil filter base and the cooler comes off. One word of CAUTION. The oil cooler hoses are difficult to find to replace. I had to get them from 2 different vendors last year, because like so many C4 parts they are discontinued. If you need them, let me know and I will dig up my old receipts. Good Luck.