M35a2 brakes??

[commandojd]

I have been restoring my m35a2 and I am getting down to the last few items to fix on my list... The main item is my brakes! I have replaced all the main brake lines, bled and put new fluid in, and removed/ cleaned the master cylinder. Everything seemed to be in working order, there appear to be ZERO leaks...but for some reason it wont hold pressure for a long period of time. About 2 months ago I re did the lines...etc and pumped the brakes up and they were functioning like they are supose to. But when I went to pick my truck up from the paint shop their was no brakes! If anyone knows what mite be going on please let me know! My buddy has three of these trucks and he never has this issue, his trucks sit for months and he can just jump in em and go with no issue. Any help will be greatly appreciated!

 

[porkysplace]

I have been restoring my m35a2 and I am getting down to the last few items to fix on my list... The main item is my brakes! I have replaced all the main brake lines, bled and put new fluid in, and removed/ cleaned the master cylinder. Everything seemed to be in working order, there appear to be ZERO leaks...but for some reason it wont hold pressure for a long period of time. About 2 months ago I re did the lines...etc and pumped the brakes up and they were functioning like they are supose to. But when I went to pick my truck up from the paint shop their was no brakes! If anyone knows what mite be going on please let me know! My buddy has three of these trucks and he never has this issue, his trucks sit for months and he can just jump in em and go with no issue. Any help will be greatly appreciated!

Did put a rebuild kit in it ? If you used the old seals it could be leaking internally . Did you follow propper bleeding procedure ? Have you rebuilt the wheel cylinders ?

 

[commandojd]

The guy I purchased the deuce from said everthing is in working condition except a broken brake line...which I repaired. The seals in the cylinder seamed to be in great shape...no visible ware. On the bleeding...I bled them properly and the brakes worked great at that time, had good pressure! The only think I didnt look at was the wheel cylinders. If those were bad, would their be some sort of leaking?

 

[DeucesWild11]

There could be a leak internally in the air pack. Check the "slobber tube" that comes down the side of the engine and see if any fluid is coming out there. Sometimes when there is an internal leak in the air pack it can vent out that tube and you'll never really see a leak. I just happen to see it dripping out there. That could be where you are loosing pressure too.

The air packs are common problems on these trucks. I did a complete teardown of mine and took pics.. here's the link http://www.steelsoldiers.com/showthread.php?82753-MY-Airpack-Rebuild-with-Photos!

 

[commandojd]

Do those cost a lot to repair?? Did you rebuild it?

 

[porkysplace]

Are you losing fluid ? how offen do you check the fluid ?

 

[commandojd]

How much fluid do they typically take? I put one quart in...It doesnt look like I lost any...its still looks full. Ill have to go look at it again.

 

[DeucesWild11]

Yes I rebuilt mine, My post has all the details of what you need. I checked Erik's and he has the rebuild kits for $108.

 

[m-35tom]

"The guy I purchased the deuce from said everthing is in working condition" remember sage advise, 'everyone lies'

 

[Heath_h49008]

This is just an idea, but have you done a major and minor adjustment on the shoes? It wasn't listed and it would explain your issues.

If the shoe adjustment isn't done, and the wheel cylinders have to travel far enough out the the bores to get the shoes to engage and build a pedal, it would explain your symptoms.

Also, it's free, and regular maintenance that you should do anyway.

Hope it helps,

Heath

 

[commandojd]

Thats a good point...ill have to take a look and see. thanks

 

[porkysplace]

Well since your having pressure issues with a single circut brake system and you really have no idea on previous maintainence on it. You should really should pull the drums and do a full inspection , it's the only way your going to know the condition of the brakes.

 

[welldigger]

Pull the rubber boot back on the MC and check for fluid. Also never take the previous owners word as gospel truth. But if I had to guess your problem is say either a bad wheel cylinder or your air pack is shot. As others have mentioned pull all of your brake drums off and inspect everything. Pull each rubber boot back on each cylinder and check for fluid seepage. Also check the slobber tube for any kind of fluid. Mine was full of rusty water. Apparently no one had drained the air tanks.... ever. This caused a bunch of water to get into my air pack. Which seized it up beyond repair.

 

[gimpyrobb]

A quick tip that has served me well through the years, instead of twenty thousandths top and ten thousandths bottom, I had adopted .015 top and bottom.

 

[welldigger]

Gimp, that just for simplicity or does that give you better/even shoe wear?

 

[Heath_h49008]

This is on my "to do" list as soon as the weather breaks. Thanks for the tip Gimp!

 

[gimpyrobb]

Just for simplicity. I have some spare shoes(imagine that) so I never cared to watch the wear pattern. I would imagine the sand and grit I pick up while off-roading would negate the .005 difference in adjustment.