My oil cooler is leaking where the fitting goes into the oil cooler. I got a crush washer from mazdatrix but it is to big and it is still liking. I tryed a Nape copper washer that was closer to the size but it is still leaking.

It is a 79 mazda Rx 7 but it seems to have fitting that is different than the pic at Mazdatrix. the fitting is flat on the hose side with a taper going in to the fitting.

Thank you Wayne'r

 

Wayne,

Might want to post a pic of the parts in question. It could be that someone changed something over the last 30 years.

 

if replacing the washer doesn't stop the leak, the threaded piece that's attached to the cooler is probably split. this is very common on these coolers. even with the washer, ppl still tend to crank down on the fitting when tightening them. with the engine running, if u wipe the area clean with a rag and watch it, u should be able to see the leak as it happens and if it is indeed on the cooler side of the washer. u may even get a helper to hold the rpm's up as to get the pressure up to what it would be as if u were driving it.

 

Hi Michael I did just as you said and when looking at from under the car (from the wheel) I could see the crack. When I put my finger on the cooler post the oil came spilling out away from my finger.

I have the oil cooler out and taking it to the radiator shop in the morning.

Thank you for the tip.

gracer7-rx7

While I have it out I will take a pic and post it. I have a fealing there have been some changes made.

Thank you for the help.

Wayne'r

 

i doubt a rad shop will be able to repair it being as it's aluminum. u'll need to find someone that can weld it.

 

Hi Michael

You were right! The Rad shop could not do it and called a Buddy and sons machine shop in Gastona NC . I took it there and they said they could do it I should know on Wed how it went. I will put up a pic when I get it back.

Wayne'r

 

I've repaired these in the past by cutting away the area that is cracked and welding on an AN male flare. The only thing about that is you then need to go to oil cooler lines with AN fittings, but then, why not do that anyway? The old ones are probably leaking.

Easier than welding, machining and rethreading...at least in my opinion.

 

Here is a pic of my cooler after it was at the shop. $30.00 to fix it. I though it was not bad at all.

 

Those welds should have been free. Wow. Now I realize that the material gets oil soaked and it can be difficult to get a good arc, but that weld shows WAY too much heat was used, not enough filler, and the tungsten hit the puddle at the end. It's clear that they didn't clean the material at all.

As long as it doesn't leak, I guess the repair works though.

 

So far so good. But we will keep an eye on it..

 

Without question, keep a CLOSE eye on that.

 

The welder should have gone all the way around that fitting .. that stuff always cracks from viberation ,, The dull surface on aluminium after exposed to the elements ( Alumimium oxide ) is the same as rust on metal it needs to be removed before welding or there are all kinds of shitty things under the weld making it very porous and weak ,It also needs to be preheated to boil the oil out of the crack if you dont it just comes oozing out as it is being welded .. No matter what it's on if you want to be confident in the repair it should be redone .. In my experience you will have it back off in 6 months or so for the same thing .. I'm not trying to pick at anyone's work so please don't take it wrong but like the man said I would keep a close eye on that.. Maybe I'm just a fussy old man I don't know....