[Vic1947]

Since getting home from the Truck Nats, I've been busy assembling a 357 Magnum engine for Scott. The chassis has just been patiently waiting its turn and I knew it needed some TLC. I'd observed that the rear bags held air just fine, but the fronts would deflate in just a few hours. So before disassembling everything to prep my homemade mounts for powder coating, I did some investigating with dishwashing soap and water. The leaks were coming from the 90 degree bulkhead fittings. They're made by Parker and have no support tube in them like the KV2 series fittings from SMC. I looked high and low for a 90 bulkhead with the support tube, but had no luck.

An alternative solution is to use a bulkhead union with a 90 elbow fitting that has one end PTC (push to connect) and the other a straight leg that fits into the female end of the bulkhead. But further research revealed that the only KV2 series elbow was for 1/4" line ...and of course I have 3/8". What the vendors are selling are the 3/8" Parker elbows without the support tube. Why all the fretting over the support tube, you ask? Well, it appears that the tight bend radius is torqueing the tubing just enough to create a leak.

So, the obvious solution is to make yer own! I had some leftover 90's with brass male 1/4 NPT on one end and KV2 PTC on the other. First step was to tap the id of the brass end to 1/8 NPT. Then I turned a brass 1/8 NPT close nipple to the dimensions I needed and assembled it using a R8 collet to keep from damaging the polished exterior. So I now have the KV2 style PTC's at every joint in the system. Hopefully it will solve the leak issues. When I get my parts back from the powder coater, I'll reassemble everything and report back.