Farmall H engine to aircleaner vent tube

JosephK · Oct 18, 2018

New Farmall H owner. Trying to identify and find new tube fittings on the crankcase vent tube connecting the rear of the cylinder head to the air cleaner housing. Cyl head fitting with the orifice is fine as well as the fitting on the air cleaner housing. The tube side fittings look like inverted flare nuts in brass. Thread pitch is 20. Diameter is 9/16. I am having a hard time finding such brass fittings. I thought initially they were British threads, but the fitting/hose suppliers say different. So far, I can find a steel brake line fitting they may work if I drill it out the center for the 3/8" tube. Any suggestions? Sources? I would say its original tubing. I need to make a new tube as I found a hole in the tube end near the cyl. head end.
The tube assembly consists of a 3/8" tube, compression sleeves on both ends with the inverted flare type nuts screwing into each end fitting (Cyl. head and air-cleaner housing). Tough to replicate so far.

D Slater · Oct 18, 2018

Think they were like the original gas lines, the sealing part of the one piece nut brakes off when tight. Don't think the case IH nut is the same as original, plus they want 25 bucks for one if still available. Unless you want original, use the good end of steel pipe in the cylinder head fitting and a 1/4 inch pipe thread 3/8 hose slide on barb in the air cleaner (unless your air cleaner type doesn't have the threads) and a 3/8 PVC hose between. Shouldn't be to hard to find a good used one if wanting original. Probably have one around someplace if you can't find one.

mattofvinings · Oct 18, 2018

So a standard tube nut for 3/8" tube is 5/8-18 thread.

when quoting 9/16-20 is that the major diameter of the male thread?

A 1/2-20 tube nut is standard for 5/16" dia tube.

It seems like being off a 1/16" could cause a lot of confusion. Are you measuring with a dial caliper or the like and a thread pitch gage ?

Summit racing has all of the above, just search "tube nut 5/8" for example to get many hits. Usually stainless or plated steel.

I really like using "corrosion resistant steel tubing" from mcmaster carr. It has a gold chromate coating which is flexible and doesn't flake off as its bent, helps a lot with not rusting. Of course you can step up to stainless steel...a regular hard-line tube bender is par for the course. I use the Ridgid 36097. There is a nicer bender, its a Ridgid 38043. Standard 45 degree single flare should be enough for a breather tube.

used red MN · Oct 19, 2018

Welcome to YT! There is a classified add section on here. If you are just looking to replace it I
would put a want add up there. I bet there are many folks that?s have a spare one from a parts
tractor laying around. Have you tried looking for a tractor salvage yard? Try Mike at the Steel Wheel Ranch in KS. I bet he has one give him a call...hit the link below.
Steel Wheel info

Farmall H engine to aircleaner vent tube

JosephK

New User

D Slater

Well-known Member

mattofvinings

Member

used red MN

Well-known Member

Similar threads