I did a quick search and did not find exactly what I was looking for so I got a question. On the oil cool it has the thermal by pass on the bottom. I have a slight leak from there. It drips not much but its annoying. I took it out cleaned it, the threaded bolt and the oil cooler. In my Haynes Manual it does not say anything about using sealant or plumbing tape, or a crush washer or anything so I just reassembled everything and tightened it down. It was dripping still so I tightened it more. Well its still leaking and I cant tightened it any more. Has anyone experienced this. I inspected the cooler for cracks but did not see anything.

 

I don't have a 1st gen FMOC handy but the 2nd gen one I have does have an aluminum washer.

 

Thanks, I figured it should have something. It did not say anything in the Haynes Manual and it did not have one when I took it out but I thought it should have a aluminum or copper crush washer. I think I might see if I can find one and give it a try, unless anyone else has any info. Thanks Trochoid

 

yep there is a washer

 

washer and make sure u buy new rubber o rings for it when u take it off. and your gonna need a set of micro wrenches.. or break a good one in half those bolts on the bottom r a pain.

 

make sure the threaded section that bolt/fitting screws into isn't split/cracked.

 

as stated, there is an aluminum washer on the bolt. i would inspect the lower bung for a tiny hairline crack. remove the oil cooler and clean it down with brake cleaner and inspect each bung. i would not attempt to tighten the fittings into the bungs on the oil cooler. you will crack them and you'll be replacing or repairing the oil cooler. at this point you may be able to tig weld the split. i have a local engine shop that repairs all of my RX-7 oil coolers. when in doubt, post a few pics of the oil cooler for us to inspect.

 

Good advice there. Rob you probably have a small crack
developing on that lower bung. Its a pretty common failure.
My SA had that problem when I first bought it in 84. I went
and replaced it with one from a junkyard back then.

My theory is if the car has ever been hit on one of the front
sides hard enough it causes these kinds of failures. I know
mine was smacked on the right front sometime before I bought
it based on how the paint has aged.