Trenton Posted July 3, 2013 Share Posted July 3, 2013 Hi folk, I need to install the airlines and quick release valve for the front brakes on my b61. Where should I install the quick release valve? The guy at the parts store told me that it needs to be located some place where both airlines to the chambers will be the same length. The only place I can see where that would be possible would be on the firewall under the windshield washer motor. Where are they normally installed on a b model MACK? I Appreciate any help you can give me. Trenton Sent from my iPad using Tapatalk HD Quote Link to comment Share on other sites More sharing options...
220cummins Posted July 4, 2013 Share Posted July 4, 2013 You should have a quick release for each set of axle Quote Link to comment Share on other sites More sharing options...
39 Baby Mack Posted July 4, 2013 Share Posted July 4, 2013 If memory serves me correctly, they used to be mounted somewhere on the front crossmember.Then run synflex lines to bulkhead fittings on each side of the frame by each front wheel then flexible rubber hoses to the chambers.Ron Quote Link to comment Share on other sites More sharing options...
220cummins Posted July 4, 2013 Share Posted July 4, 2013 If memory serves me correctly, they used to be mounted somewhere on the front crossmember.Then run synflex lines to bulkhead fittings on each side of the frame by each front wheel then flexible rubber hoses to the chambers.RonI drilled and mounted mine on the front rad support with plumbing as you stated. Quote Link to comment Share on other sites More sharing options...
39 Baby Mack Posted July 4, 2013 Share Posted July 4, 2013 That'll do it.Ron Quote Link to comment Share on other sites More sharing options...
rsb502 Posted July 4, 2013 Share Posted July 4, 2013 Yep pretty much all truck makers mount the front axle qr2 on the crossmember forward of the axle. I have seen some mounted on radiator brackets and one bolted to a bumper before but the crossmember is oe style and probably the safest bet. Make sure you run equal length lines from each side if one is longer the short side will activate faster and the long side will release slower and you'll get brake drag and possible control issues on slick roads. 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 Share on other sites More sharing options...
Trenton Posted July 4, 2013 Author Share Posted July 4, 2013 To All, Thank you for the quick response. I will mount it on the front cross member as suggested. Thanks again Trenton Sent from my iPad using Tapatalk HD Quote Link to comment Share on other sites More sharing options...
Maddog13407 Posted July 4, 2013 Share Posted July 4, 2013 they don't have to be equal length and never were on a B model. on a B model they were mounted on the driver side between the fuel tank brackets inside the frame rail. if there was a front wheel brake control valve it was mounted here in place of a quick release valve to limit the air to the front brakes in inclimate weather. from here the line for the pass side ran backwards, around the cab mount crossmember then down the pass inside frame rail to a bulkbead fittin that went thru the rail and connected to a rubber hose then the brake can. the driver side ran down the left inner frame rail, under the steerin box and into a bulkhead fitting. most B models I have seen up here in New England have the front wheel control valve instead of a quick release valve to limit the air. same deal on air lines except the front wheel control valve version had another line that runs back to the flipper switch on the dash. there should already be two pre drilled holes from the factory to mount the valve between the fuel tank bracket bolt holes on the driver side inner frame rail. Quote Link to comment Share on other sites More sharing options...
39 Baby Mack Posted July 4, 2013 Share Posted July 4, 2013 You're right Matt,the "B" models we had all had front brake limiting valves on them, our early "F" models had them also.I know on the "F" models they were mounted on a bracket that was welded to the radiator support.And now that you mention it you're right about where they were mounted on a "B" model, it's been a long time ago!Ron Quote Link to comment Share on other sites More sharing options...
rsb502 Posted July 5, 2013 Share Posted July 5, 2013 You're right Matt,the "B" models we had all had front brake limiting valves on them, our early "F" models had them also.I know on the "F" models they were mounted on a bracket that was welded to the radiator support.And now that you mention it you're right about where they were mounted on a "B" model, it's been a long time ago!Ron[/quoteI haven't ever messed with the brakes on a B but I did take a Bendix air brake class and they said brake lines were to be equal length for the brakes to apply and release in sync. I always wondered if they took into account lack of grease and old springs when they got into their specs, but equal length lines does make sense for an air system. I'll bet engineering that far in depth wasn't even thought of when they started building B models, the times they have a changed fur sure. 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 Share on other sites More sharing options...
Trenton Posted July 5, 2013 Author Share Posted July 5, 2013 It's interesting to read that MACK installed them on the drivers and ran the right side airline around the back of the cab. The airlines would be far from equal length with that set up. I took the earlier advice and have mounted my quick release/limiting valve on the front cross member. Thanks for the input. Trenton Sent from my iPad using Tapatalk HD Quote Link to comment Share on other sites More sharing options...
rsb502 Posted July 5, 2013 Share Posted July 5, 2013 It's interesting to read that MACK installed them on the drivers and ran the right side airline around the back of the cab. The airlines would be far from equal length with that set up. I took the earlier advice and have mounted my quick release/limiting valve on the front cross member.Thanks for the input.TrentonSent from my iPad using Tapatalk HDHey if thats all thats changed in the last 60+ years were good, LOL! 1 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 Share on other sites More sharing options...
39 Baby Mack Posted July 5, 2013 Share Posted July 5, 2013 Hey if thats all thats changed in the last 60+ years were good, LOL!Ain't that the truth!Ron Quote Link to comment Share on other sites More sharing options...
Trenton Posted July 6, 2013 Author Share Posted July 6, 2013 I suppose your right! Trenton Sent from my iPad using Tapatalk HD Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.