Hi all,

This is a cross-post with another forum but since after doing an extensive search on this forum in which I did not find any other posts quite like it, I thought it would be ok to post it here too in case someone in the future might find it useful.

Issue: Leaks at adapter between engine block and the oil cooler lines. Loss of oil was getting gradually worse and making a mess. Having had the gaskets at the adapter fail catastrophically on a 1992 Blazer, and knowing that the oil lines tend to go out at 150,000 miles (I'm at 135,000) I thought it best to replace the parts now.

Parts Used: Gaskets and lines from the local GM dealer. I did not want to ever have to do this repair again! I had read many bad stories about the Dorman oil lines and that some brands of the gaskets for the adapter do not work very well. I'm hoping that I'll get at least another 135k miles out of these new OEM ones.

Issues: Access, access, access! Getting to the bolt that holds the oil lines to the adapter on the block is a challenge. I've seen suggestions of detaching the front axle assembly to lower it, removing the bolts for the engine mounts and raising the engine, and raising the engine without removing the mounting bolts. After examining the access for the bolts that would allow me to lower the axle or raise the motor, I decided that getting to them would be a major hassle too. So I went with what many have done, raise the motor without undoing the motor mounts.

Now, there is a potential problem in that the insulators could become damaged. So I raised the motor (with a block of 2x6 under the oil pan) only enough to get access to the bolt on the end of the oil lines. I did not want to raise it more than I had to in order to prevent any damage to the engine mounts. I found the amount to raise it by trial and error.

To get to the bolt I had to use a long extension from the front of the motor along with a toggle joint at the 13mm socket.

In order to get the bolt back on, I inserted the new oil line in then started the bolt in by hand by reaching up from directly below. What I found useful was to have the adapter block installed but the two bolts not tightened down so that I could have more freedom to reach the oil line bolt.

The oil line to engine block adapter: Whooee, was that annoying. I found it extremely hard to get out once the bolts were out. I tried with the motor raised and lowered in its original position. I was finally able to get it out by orienting the oil line holes downward and at the correct rotation I could slip it past the u-joint and front differential. I think I got it out with the engine down. It is a tight squeeze.

To get the adapter back in was very hard but it can be done from directly beneath the point where it mounts. In addition there were the o-ring and gasket to install.

To get the o-ring and gasket installed I borrowed a trick from engine builders who use Vaseline to prime their oil pumps in newly built motors. Not wanting to press my luck, I used just enough to keep the o-ring in the groove of the adapter and to hold the gasket in place on the machined surface of the block into which the adapter mounts. This worked really well. I don't know how I would have gotten the gasket installed otherwise.

Once the adapter was in loosely with its mounting bolts I then attached the oil lines (as described above). I torqued the oil line bolt after screwing in the adapter bolts all the way in and then backing them out just a bit to allow some "wiggle room" for the final tightening of the oil line bolt. Once the oil line bolt was done, the adapter bolts were easy.

I saved the front oil line bolt for after the other end in case I needed to be able to move the oil line during the rest of the installation.

Finally a real bear was to reattach the mounting bracket for the oil lines to the oil pan. It is a 10mm bolt and it was very hard to see to align it. A 1/4" drive socket set, 3" extension, and ratchet wrench help there.

Total time to do replace the parts was about 4 hours.

Christine

 

Sounds like a job well done.
Thanks for the extensive post.
May need to use this myself one day.

 

Well as far as using GM lines , they are only marginally better than the Dorman...at least Dorman has a lifetime warranty. They will have to be done again. If you still own it when that time comes , cut the old hoses off , use oil resistant rubber line and double hose clamps......then you will have a permanent fix.

 

Yes, Ideally I probably should have made my own with the double hose clamps. I drive my Blazer less than 7,000 per year so assuming the new lines work at least as well as the originals, I think (hope?) I'll be good for a long time. Then again, we all know what happens when we assume too much! ;-)

Christine

 

Well if you have a place to store the old ones you can fix those ones up and have them ready for install....if needed. But your right they are going to last years anyways.

 

You may want to have a look at these threads as well.
The advantage is that now the oil lines are three pieces which can be bolted on so much easier.

Had to change them about 8 years ago. Still no drop of oil ever leaked past the fix.

Had changed them with GM because of leaking and two years later I'm at the same situation. Leaking.

Used a set of old ones from a scrap yard and my friendly hydraulic hose team.

https://blazerforum.com/forum/engine...-repair-88354/

 

Thanks for the extra links. For the time-being, the new ones are staying it. If I do find new leaks (which I really hope I don't), I'll have two advantages over this first reinstall:
1) I will be able to get them out faster having had practice. (LOL)
2) I will have the old set I can have made up in a proper way with better attachment of the flexible/rubber hose part.

Thanks!

Chrisitne