wacatak Posted December 5, 2013 Share Posted December 5, 2013 I have a 1991 rd 688 with a eaton drag axle when I engage it the valves coming off the drag axle keep bleeding air. When the truck is at an idle it bleeds out faster than it can maintain. If anyone has any ideas or any info would it would be greatly appriciated. Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/ Share on other sites More sharing options...
hatcity Posted December 5, 2013 Share Posted December 5, 2013 the valve is cheap and relatively easy to replace. Make sure the airlines aren't leaking and the bags also. Quote Success is only a stones throw away.................................................................for a Palestinian Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220037 Share on other sites More sharing options...
wacatak Posted December 6, 2013 Author Share Posted December 6, 2013 The 2 valves that are leaking are tied together between the airbags and mounted to the frame. I believe the manufacturer is midland, when i engage the axle they just keep bleeding air. Thanks again Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220092 Share on other sites More sharing options...
thomastractorsvc Posted December 6, 2013 Share Posted December 6, 2013 the valve is cheap and relatively easy to replace. Make sure the airlines aren't leaking and the bags also.as was said check the air lines to make sure not damaged, if they are ok replace the valve Quote Robert"I reject your reality and substitute my own." Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220094 Share on other sites More sharing options...
blackdog2 Posted December 6, 2013 Share Posted December 6, 2013 Sounds like a quick release valve gone bad . Quote Ed Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220116 Share on other sites More sharing options...
rsb502 Posted December 6, 2013 Share Posted December 6, 2013 whats a drag axle? a tag axle? Is it air up air down, or spring up air down? is the air leak only present with the parking brakes released? does it have spring brakes? Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220181 Share on other sites More sharing options...
wacatak Posted December 8, 2013 Author Share Posted December 8, 2013 sorry tag axle. it is air up and down steerable and air brakes. The leak is present with brake on or off. The mack dealer tried to get some info from eaton with no success. Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220417 Share on other sites More sharing options...
rsb502 Posted December 8, 2013 Share Posted December 8, 2013 Its only got a few parts, four air bags, a 6 lines and maybe two or three valves depending on arrangement, you have a valve to operate it swapping the supply air from the regulator from the up bags to the down bags and bleeding the up bags at the same time, if its not a bad air bag and it is actually coming from the valve it is a spool inside an aluminum valve, the spool moves back and forth inside the valve body porting regulated air from one side to the other and venting the other, sounds like bad o rings in the valve to me. they are std. o rings if its the same valve as in a Watson Chalin axle and easy to get out of most good o-ring kits. I haven't ever seen an Eaton tag axle but that doesn't mean much, I guess eaton makes axle tubes for tag axle assemblies but I didn't know they made the valving and brackets for any of them, Hendrickson, Neway and Watson Chalin are the top three. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220420 Share on other sites More sharing options...
rsb502 Posted December 8, 2013 Share Posted December 8, 2013 Got a pic of the valve the air is coming from? Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220421 Share on other sites More sharing options...
wacatak Posted December 8, 2013 Author Share Posted December 8, 2013 yes i have a pic on my phone i just have to try to figure out how to load it on here. The name on the 2 valves is midland ill try to get the pic uploaded. Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220446 Share on other sites More sharing options...
wacatak Posted December 9, 2013 Author Share Posted December 9, 2013 here is two pics, hope they will help. Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220458 Share on other sites More sharing options...
rsb502 Posted December 9, 2013 Share Posted December 9, 2013 that's a QR2 quick release valve, same thing you would find on service brakes on your non parking brake axles but there would be a line on the other side not a plug, so one line goes to the control valve and the other to the air lower bags? if so swap that valve, take it off and carry it to any truck parts place and they should have one, it doesn't matter pete, kw, mack, international, fleetpride whatever you can get one there. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220462 Share on other sites More sharing options...
wacatak Posted December 9, 2013 Author Share Posted December 9, 2013 there are two of these tied together one for each side and they both are leaking air, so its possible for both of them to be bad? Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220466 Share on other sites More sharing options...
rsb502 Posted December 9, 2013 Share Posted December 9, 2013 Nope not likely, what are they plumbed into and how many lines are there on the other one? If they are ties together does the other side have the same setup? Does the line from the top of this one go to the top of the other one and a T then off into the frame? I'm guessing the raise lower valve is bad but the #1 quick release valve could be bad, hard to tell without Being able to see the plumbing.if this is on the down press bags then the pic you have there the line on top is supply air and the line coming out of the side should go to the air bag. That would mean there was a T somewhere to get one line from the control valve tied into both QR valves. Quote "Any Society that would give up a little LIBERTY to gain a little SECURITY will Deserve Neither and LOSE BOTH" -Benjamin Franklin"If your gonna be STUPID, you gotta be TOUGH" "You cant always get what you want, but if you try sometimes you get what you need" Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220511 Share on other sites More sharing options...
wacatak Posted December 10, 2013 Author Share Posted December 10, 2013 im going to be away from the truck until the first of the week.Then I will get it in the shop where I can take a look at it to see where the lines are going. So ill post then to see what I have to replace to get it fixed. thanks again Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-220663 Share on other sites More sharing options...
wacatak Posted December 16, 2013 Author Share Posted December 16, 2013 well i got back to work on the truck today and i believe i have fixed it. I traced the lines back to the valve/regulator i dont know the correct name but it is the valve where you can set the pressure, i pulled it apart cleaned it and stetched one of the springs to give it a little more tension and it seems to be working. Let me know your thoughts. Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/33762-drag-axle/#findComment-221663 Share on other sites More sharing options...
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