97 Blazer oil cooler lines leaking
 

My daughters 97 Blazer started to leak oil at an alarming rate so I needed to fix it. The leak was at the rear of the engine so I started looking for possible points of a leak, then the transmission failed.

While the trans was out the rear main seal was changed and a 4 inch long crack was found in the oil pan just below the rear seal. With all of those fixed I was able to start cleaning up the oil mess on the rear of the engine. That is when I realized that the oil cooler adapter was leaking too. After looking up all the oil cooler leak threads on this forum I was only partialy convinced on how to fix it. Here is what I found......

The oil cooler lines are prone to leak at both ends. There are a few ways to fix the lines and I chose to replace them with the Dorman replacement. Getting the lines out was difficult but doable. The 97 has the lines attached at both ends with a 13 mm head bolt and the hanger clamp has a 10 mm nut on it. I was able to reach the bolt holding the cooler lines to the adapter with a long extention, wobble joint and 13 mm socket. I used a 2x4 block against the front section of the oil pan and was able to jack the engine up, without removing the motor mount bolt, to get the lines out. It only took about 1/2 to 3/4 of an inch to get the lines out.

The adapter was another chore...two bolts with 13mm heads on them hold the adapter on which are easy to get to and you'll have to pry the adapter loose. Getting it out will take a fumbling puzzel job and I found that I needed to turn the front drive shaft in order to get it to pass by the shaft.

The adapter and the mounting point of the adapter on the engine need to be carefully cleaned. If not, the gasket on the center of the adapter will not allow the adapter to pull down tight enough to properly compress the large O-ring around the outside rim of the adapter. I needed to use a single edged razor blade to clean out the engine side of the mounting point. There was part of the old gasket stuck inside the boss. This area is difficult to see and reach but it MUST be done.

The only RTV needed is to glue the new gasket and O-ring to the adapter to hold it in place in order to position it back on the engine. A fine flat file was used to clean up the burrs on the gasket mounting surfaces.

To reinstall the lines is to reverse the dissassembly order. The mounting flange of the lines must be carefully inspected. I found a nick on the mounting surface of the NEW lines and removed it with the flat file.

We'll see if it totally fixes the leak.......

I have not had a problem with O ring ends at all so far. All my issues were with the thin weak rubber hoses and the pressure connect aluminum ends that hold them on. If you live in a part of the country that gets winter and very cold weather they don't last. After replacing them 3 times I took my 4th set to a local hose shop and had the weak hoses replaced with high pressure hose and fittings. I haven't touched them in 4 years now. I wish I would have done it sooner and saved myself a lot of swearing.

Hey thanks for the thread! How did it work out for you? Any more leaks? I changed the lines out on my 2000 Blazer, but its leaking at the adapter... just got back from the dealership with the new gasket and oring (I've read on the forums tyat the aftermarket ones leak almost immediately after install).

never a issue with aftermarket repair kits. The lines aint worth a darn,but the orings etc is fine. people just over torque em.


if all else fails,and you dont care about the oil cooler. pull the adapter off,take out the nipple the oil filter screws onto (has allen head,or torx head screw in the center) and screw it directly into the block. be done with all the line/adapter leaks. Unless you are heavy towing,or extremely hard on your engine,you wont miss it.

Well I'm not too worn out on the problem just yet... im in the middle of it and ive ran into a problem im not quite sure how to handle... i cant get onto the block with a razor blade to get the old gasket off. I have an angle grinder that would do the trick but there is just no room to get it up on there.

I see the op said to use a "single blade razor"... im thinking of like a disposable face shaving razor??

I would just eliminate the whole oil cooler crap. That's what i dis on my 3 vehicles, a blazer, jimmy, & sonoma. I had nothing but problems, used all new parts, & would not stop leaking, no matter what i did. Tired of wasting my money to see it leaking all over the driveway. Just go to your local dealership & order gm# 14081300 around $12, $8 something at wholesale cost. Remove oil cooler adapter, thread into block, use allen bit & tighten up. For filter i am using a dodge neon purolator gold PL10241, might have to put a jack under oil pan & slightly raise up a little. It works great, no more leaks, & way better oil pressure to. Goodluck

If i end up having to deal with it again i probably will change it over. For now it's not leaking so im happy 8-)

the nipple is already on your blazer. just remove what the filter threaded onto. its the same part. done it on 2 of mine.

Not going to start an argument Chris 15. They are not the same, they might look it. You might be able to use it, but they are not the same. The one on the oil filter adapter does not have a hex in the inside of fitting used to tighten it. I could not get mine to come loose or i would have tried to used them. I just double checked before i posted, they are not the same! Best thing i have ever done eliminating all tat bs.