Im putting metal stems in a set of tubes, How tight do you tighten the nut? Do you put the bridge washer parallel with the tube? Do you use any sealer? Any hints appreciated. Thanks.
I installed metal valve stems in five tires over a year ago and had the same question you do. I tightened the nuts moderately tight, but not over tight (squeezed the rubber too much). I used no sealer. The five tires are still at 35# of air, so I guess I tightened them OK. I put talcum powder in the tires before I installed the tubes to reduce chaffing.
Rusty Nelson
You got good answers. Washer parallel and no sealer. I tried sealer once and it acts as a lubricant making it easier for the tube to slip out of the clamping action. They need to be quite tight but I never checked the torque. If the stems are not tight enough they act as pressure regulators. If one always leaks down to the same pressure it is not tight enough.
A trick that I got from RockHill Will (Will Cronkrite) is to install the stems in the tubes and then air them up ....for a month or two before installing them in the tire. If after a month they are still holding air, then your in business. If one has deflated, then you can easily fix it w/o having to break-down a tire and chance scratching a rim.
I learned the hard way back in the 70's that rubber gaskets (and inner tube stems) are instally DRY. I had to redo the intake rear rubber 3 times in two days on a Chevy V8. It didn't leak running in the shop, but leaked bad on the road test. Finally an older experienced mechanic asked me if I was using any sealer on the rear runner gasket. I told him I was and he told me they must be dry. He was right!
Tom, you probably do/did this too, but on those I use a centering punch and go down the rail and hammering a dimple in the rail about ¼" apart where that rubber can squeeze into when it is compressed. They don't move then!!
Wow what a timely thread! I had my coupe on jack stands to do some brake work but I had to move the car. I need to air up the tires at which time two of my rubber stems broke off. I decided to replace them with metal one. So this information was good timing. Thanks Richard/Ca.