Re: Air pressure on the brakes of an M1081!

[Suprman]

Easy way to test the dryer is to bypass it temporarily. Just connect the in and out air lines together. There are check valves behind the air tanks if one tank does not seem to fill up you can take them apart and check them. The unloader has lubricant in it which dries out and turns into hard pieces when sitting for a year unused in hot weather. Sometimes driving it will help loosen the stuff up. When the air dryer cycles you know you have reached governed pressure though. Turning it up a tad cant hurt. Governor is on the compressor.

 

[FloridaAKM]

Okay, after getting home & starting her up, I turned off the cab air @ the hydraulic panel & watched the brake air guages. Front air pegged as the rear air hit 75 psi. The rear brake air maxed @ 100 & then you could hear the air coming out of the drivers side air bag; getting down next to it, you could feel the air blowing out of the metal protective cylinder that houses the air bag. PM your price on a replacement air bag for the left (drivers) side. I am going to pin the cab for now & remove the air bag to insure that is what is leaking. This is reminding me of a boat I have, you know the rest of the story!

 

[mkcoen]

This is reminding me of a boat I have, you know the rest of the story!

Been there, done that, and got a LMTV hat to show for it. My $8200 M1078 has passed $12k, granted a lot of that money was for non-necessities to pretty it up but still, these things are money magnets.

 

[Suprman]

Dont pin the airbag. Just turn them off. I dont usually drive with the air ride on it dosnt make a huge difference. I have new and used ones.

 

[FloridaAKM]

Turning them off didn't make a difference in the air loss during the inspection time of 15-20 minutes. I think my happy ride down 5 miles of dirt road caused the left airbag to rupture & make the entire brake system start to drag. I will probably be proved wrong in my thought process, but @ least I tried to figure thru this calamity...........

 

[FloridaAKM]

My $$$ whirlpool is less than yours, but is trying real hard to equal it. I am working on necessities only for now to get her running for the meet this fall here in Florida, but I am failing to get the darn brakes to act right. It looks like I will be bring the Deuce to the meet as she is/has always been 100% reliable for everything from recovery to today. I want to take the LMTV to work @ least to show the naysayers there that these trucks are awesome, but you all see my issues with mechanical stuff along with NO title from GP.

Been there, done that, and got a LMTV hat to show for it. My $8200 M1078 has passed $12k, granted a lot of that money was for non-necessities to pretty it up but still, these things are money magnets.

 

[Suprman]

No air to them with the knob off. Air is prob leaking elsewhere or the control is bad.

 

[FloridaAKM]

Today was the day to remove one of the leaking cab support air bags for inspection, after the fun of working in the July Florida heat; the air bag was removed
& tested & it was a bigtime leaker around the base, which I thought so after a short run a week or so ago. As per Suprman's instructions, turning off the air allowed the pressure to build to 120 front & 110 rear to allow the brakes to release, the fan clutch to release, the air dryer to purge as normal & the truck to be drivable around the property. Since GP still has not gotten a Title for me on the truck, no road tests on this truck!!!

 

[FloridaAKM]

While I was idling the truck, watching all the functions on the dash panel, the voltage would start out around 26 vdc on the guage. After running for 15-20 minutes, the guage would drop into the yellow area below 24 vdc range, what gives with the voltage drop on hot batteries?

 

[Suprman]

Disconnect and tape off both wires going to the alternator regulator. Take the positive lead from the fuel solenoid (outer usually but confirm with meter) and bring it around the front of the engine and connect to the +24 volt terminal on the regulator. Do not connect anything to the terminal marked AC. Go for a test drive.