Heavy Equipment Forums Heavy Equipment Community

Brake air valve above drive axles?

Hallback ยท 2018-04-04 22:30

I know it is not really a truck question but the valve above the drive axles on a Skagit yarder that operate the spring brake cans has about 8 different fittings coming off of it going to the brake cans. What is the name of that valve?

Replies14
  1. #1Hallback2018-04-04 22:31

    And would that be the cause to not have any brakes if that valve was bad?

  2. #2Junkyard2018-04-04 22:44

    Relay valve. Might be full of trash, no air to it. More often than not it's gotten crap in it and the diaphragm is stuck. Clean it off and determine which is main supply (might be marked reservoir), usually a large line in, and see if it's got air. Next find supply line and see if you have air when you step on brake pedal. If those are good I'd say it's fubar. The smaller lines out will be release air for springs and apply air from pedal. They're not very expensive. If something is acting up I usually just change it.

  3. #3Hallback2018-04-04 22:47

    Okay, thank you. I know air flows through it as we knocked the back of one of our spring brakes off when we were moving the yarder and it was pissing air like crazy until we capped it off at that corner. Are they Universal or are there many different types?

  4. #4Junkyard2018-04-04 22:52

    There are a handful of common ones. If there's still a little metal tag under one of the bolts that will tell you what it is. A good parts guy can set you up with one by a pic or two. It may not look identical but it'll function the same. Main thing is fitting sizes so you're not changing a bunch of hose ends.

  5. #5willie592018-04-04 22:59

    What Junkyard said.

  6. #6Hallback2018-04-04 23:06

    Okay, sounds good. I will get underneath there and get a bunch of photos of it tomorrow as I don't want to pull it out until I have a new one to replace it so the yarder can still run.

  7. #7Hallback2018-04-04 23:09

    I pulled it apart to clean it out one day when we were moving the yarder and had no brakes. It had a ot of trash in it and now is dumping air out of the quick release. It has to be junk.

  8. #8Junkyard2018-04-04 23:19

    It's hard to clean one and have it work like it's supposed to. I seldom get lucky but it has gotten me off the side of the road or out of the middle of whatever nowhere I was in. I've also noticed the newer valves having poorly casted parts as well as cheap rubber. Heck how long has it been since there was a core on a valve? What does that tell us?!?

  9. #9Hallback2018-04-04 23:22

    So very true!! This one still had original Skagit yellow on it under the blue paint!

  10. #10willie592018-04-04 23:29

    Air relay valves are like a BIC lighter nowdays, use it until it quits, toss it, replace.

  11. #11Junkyard2018-04-04 23:41

    Probably older than me! Which isn't sayin too much haha

  12. #12Junkyard2018-04-04 23:42

    That's a fact. Seems like everything is.

  13. #13Birken Vogt2018-04-05 00:11

    And some of them are made of plastic, too.

  14. #14Truck Shop2018-04-05 07:26

    Figuring it does not have ABS or even if it does, the most common is the R-12 or/ then the next common most common R-14 Bendix. Truck Shop