Oil Cooler Line Question
 

I am at my end with this whole oil cooler line nonsense.
First after winter, I had a leak from the flared fittings at the sandwich plate.

Perrin sent me new lines.

I re-installed, and had no issues but then I had a leak from the mocal rubber sandwich plate gasket.

So I ordered a brand new mocal plate and Perrin sent me new O rings for their spacer. Installed and now the fuking flared fittings are seeping underneath again from the lines. I am using a paper tower rubbing underneath fittings and their is fresh oil, very little.

I tried installing where fittings screwed on easily then hand tight then snugged them. Leaked. Then really tightened them, same crap.

They are flared fittings, not rocket science but can't understand what the hell I am doing wrong here. Any advice?

Terry at @Maximal can probably hook you up with a different style fitting/line.

Starting to feel your pain with your oil cooler problems man. Hope you sort it out soon!

Thread sealer?

why not try a different brand of AN fitting? can you see the impression of the cone sealing face on the end of the AN adapter from the plate?


Speedflow sells AN caps that fit on the cone face to seal damaged fittings

Not recommended for flared AN fittings.

Ordered conical washers as you mentioned. If its good for aviation should be good enough here.

AN fittings are designed to be snug but not as tight as you'd expect for threading as large as they are. I believe the Perrin cooler comes with -10 AN which you'd want to tighten to around 33±3 lb*ft. You can use a crow foot on a torque wrench or hand tighten to snug then tighten an additional quarter inch. The flared fittings are anodized aluminum right? Check the surface of the flare and cone and see if they are marred up or scratched as JP mentioned. It should be obvious since they start black. If they are good, try tightening using those specs/method and see if it leaks, otherwise try the washers.

The washers for sealing are called "del seals"

http://www.delaerospace.com/files/23000507.pdf

Noted - it makes me want to take a better look at the Cusco water cooling system as opposed to this.

with quality fittings you wont have any leaks. The QC isn't always perfect on the China/TW sourced fittings.

I run the OEM Forester XT oil-water cooler from the 2.0DIT which I believe is very similar to the Cusco system (and a heck of a lot cheaper) and it works pretty well. One thing to note is that since they inherently operate off temperature deltas the temps will be a little higher than those of thermostatic air-oil coolers. Upside is that no worry of damaging the cooler and springing a leak since there's no front mount air-oil unit and it doubles as an oil warmer on cold startup :D. It should be adequate for most DD and light autoxers like I plan to be. I will be installing a Vortech SC soon too.

Perrin uses Aeroquip fittings which from what I understand are quality.
http://aeroquipperformance.com/p-24061-fittings.html

I used an aluminum wrench for tightening to avoid damaging them as well.
Was very careful installing lines, just must have a run of bad luck.

Going to install the conical washers and report back.

Dezoris, it could be that the oil is coming from the inside the fitting, and when tightened up, and the car heats up for the first time, a few drips out, but then it should stop.

It also could be there is a burr on the inside of the fitting where it seals to the male fitting. If that happens, the fitting will never seal right, since it's a mechanical seal, and it'll continuously leak.