MILEAGEMAN Posted July 15, 2020 Share Posted July 15, 2020 I have a 1967 R700 Mack. The air valve under the brake pedal under the cab fire/wall is leaking. Can someone please tell me where the best place is to purchase a new one. any help is appreciated. thanks Quote Link to comment Share on other sites More sharing options...
h67st Posted July 15, 2020 Share Posted July 15, 2020 If you could post a picture of the valve we may be able to help. 1 Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 15, 2020 Author Share Posted July 15, 2020 great will do later today Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 16, 2020 Author Share Posted July 16, 2020 Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 16, 2020 Author Share Posted July 16, 2020 the number on the valve is 239649-A and the tag number on the valve is A21690 Quote Link to comment Share on other sites More sharing options...
Popular Post h67st Posted July 16, 2020 Popular Post Share Posted July 16, 2020 That's probably a Bendix E-6 treadle valve, you should be able to take it to a truck parts place and have them match it up. One caution is that you could have a maxi brake can with a shaft seal leaking that will cause air to leak back through this valve. 3 1 Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 16, 2020 Author Share Posted July 16, 2020 there is a brake can leaking also on the truck. if i took the valve off for no reason im going to cry. Quote Link to comment Share on other sites More sharing options...
fjh Posted July 16, 2020 Share Posted July 16, 2020 (edited) 54 minutes ago, MILEAGEMAN said: there is a brake can leaking also on the truck. if i took the valve off for no reason im going to cry. To Late now its Spilt Milk! The Gas companies here where I live advertise on tV all the time ! CALL BEFORE YOU DIG ! I think that applies Here! Edited July 16, 2020 by fjh 2 Quote Link to comment Share on other sites More sharing options...
kscarbel2 Posted July 16, 2020 Share Posted July 16, 2020 Mack part-no. 20QE3183R Quote Link to comment Share on other sites More sharing options...
KKERGALL Posted July 16, 2020 Share Posted July 16, 2020 Pretty sure it should be a E3 / 20QE369 if I remember correctly and I think 20QE186A switch / check valve. Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 17, 2020 Author Share Posted July 17, 2020 thanks for all the help I got one ordered. Quote Link to comment Share on other sites More sharing options...
KKERGALL Posted July 18, 2020 Share Posted July 18, 2020 What did P/N# end up being? Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 19, 2020 Author Share Posted July 19, 2020 the truck shop used 239649-A that is stamped on the valve. it comes in Tuesday. Quote Link to comment Share on other sites More sharing options...
Popular Post davehummell Posted July 19, 2020 Popular Post Share Posted July 19, 2020 I always checked if the brake canisters were leaking anytime there was an air leak problem I had fittings made up I could block off the lines it really helped diagnosing air problems. the treadle valve placement was a real pain on some truck manufactures. I liked Mack you could take up the floors and get to things, the other trucks were made by people that never turned a wrench 2 1 Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 21, 2020 Author Share Posted July 21, 2020 i like old trucks and always wanted a wanted twin stick with a jake brake. a farmer had this mack a mile from my house and hadn't used it in ten years. the problem obviously is i dont know much about trucks so the honeymoon period is rapidly vanishing. thanks for everyone's help and patients. Quote Link to comment Share on other sites More sharing options...
doubleclutchinweasel Posted July 27, 2020 Share Posted July 27, 2020 I think I bought all my reman Bendix stuff from the local CarQuest. Got quite an education doing the air system, too! 1 Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment Share on other sites More sharing options...
mechohaulic Posted July 28, 2020 Share Posted July 28, 2020 no where in the conversation was it stated whether the valve was a constant leak or when brakes are applied. brake cans leaking internally maxi to service usually exhaust out the frame quick-release valve . being new to owning a '70's mack; hope you pay very close attention to the how's and proper way to change a brake can!!! I would doubt the cans are original. the old cans were able to have BOTH diaphrams changed. fortunately new cans are no longer able to disassemble maxi side.. Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 28, 2020 Author Share Posted July 28, 2020 the valve leaked when i released the brakes. i put the new valve on and it leaked when the brakes were applied and released. i caped off the two air lines going to the leaking brake can and that didnt help. i ordered another valve. im at a loss. Quote Link to comment Share on other sites More sharing options...
doubleclutchinweasel Posted July 28, 2020 Share Posted July 28, 2020 (edited) I have a bunch of Bendix air valve info, if I can just figure out how to put it here in such a way that you can open it. I keep trying to attach some of them here, but when I click on them, they won't open. I'll try to figure it out. Seems like I've had this problem before. Edited July 28, 2020 by doubleclutchinweasel Quote "Eagles may soar, but weasels don't get sucked into jet engines." Link to comment Share on other sites More sharing options...
mrgumby Posted July 28, 2020 Share Posted July 28, 2020 Make sure the quick release valves are working if not they will bleed off through the brake valve Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 29, 2020 Author Share Posted July 29, 2020 the release valve isn't leaking. could there be other issues with it? Quote Link to comment Share on other sites More sharing options...
mrgumby Posted July 29, 2020 Share Posted July 29, 2020 Not leaking but when you take your foot off the brake pedal is it exhausting the air I’ve had them not releasing air and releases back through the foot valve. just a thought Quote Link to comment Share on other sites More sharing options...
mechohaulic Posted July 30, 2020 Share Posted July 30, 2020 On 7/27/2020 at 11:20 PM, MILEAGEMAN said: the valve leaked when i released the brakes. i put the new valve on and it leaked when the brakes were applied and released. i caped off the two air lines going to the leaking brake can and that didnt help. i ordered another valve. im at a loss. did you take off the SERVICE line on the other cans and release the brakes; with the wheels chocked of course. possibly another can is by-passing you can't hear. is the pedal itself working free and not oxidized to mount sticking partially on. with parts today , could be bad new valve. does it have a trolley valve that may be part way on ? did someone have lines off a can then put them on backwards ? these may sound like dumb questions, after xxxxxx yrs of 24/7 road calls ; you get to where you have to start basic with questions. 35min trip on road for liftgate not working --- power cord to trailer not plugged in. next call for same , I said to driver :" is power cord plugged in ?" ; reply - yes it is .... 40 min trip front of trailer power cord hanging . I said "thought you said cord is plugged in!!!!!! . he points to LIGHT cord and says that's it right. light cord green , 2 wire power cord black ... OK I'm paid by the hr, still have rest of fleet to maintain. Quote Link to comment Share on other sites More sharing options...
MILEAGEMAN Posted July 30, 2020 Author Share Posted July 30, 2020 that is a mouth full^^^^^^^^^^^^^^^^^^the first thing i was told to check was to make sure the brake pedal wasnt stuck or sticking. what is a trolley valve? Quote Link to comment Share on other sites More sharing options...
KKERGALL Posted August 4, 2020 Share Posted August 4, 2020 valve on steering column Quote Link to comment Share on other sites More sharing options...
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