M35A3 Low Air Buzzer While Steering

[glcaines]

Navo, I have had the same problems as you with my A3. I've also experienced the same problems AceHigh mentioned. If the problem is the valve AceHigh mentioned, hitting it with a rubber hammer is not adequate. You need to really whack it with steel. At least that's what mine takes when it sticks. when mine sticks, the pressure on the gauge stays at zero, but the pressure-relief valve starts dumping air. This valve is designed to prioritize air pressure to the brakes in the event of a major air leak, such as the air assisted steering failing. A few quick whacks with a hammer or wrench will cause mine to release. The other issue I've had with mine is with the steering. If you look at the actuator, there are two exhause lines that merge into one line that dumps air when the steering wheel is returned to neutral. Disconnect both exhause lines. Have someone try to turn the steering wheel until the low air pressure buzzer sounds. If the seals are leaking, you will see air escaping from one of the exhaust lines. In my case, I have had both problems. To try to fix leaking air seals in the cylinder, I jacked up the front of the truck so that I could easily cycle the steering wheel back and forth from left to right lock and back again. I disconnected the air input line to the steering system and squirted a few ml of air tool oil into the system. I then hooked up the air lines and started cycling the steering wheel from lock to lock, dozens of times. I saw an almost immediate improvement and the problem eventually completely went away after months of driving. The only problem now is that I still have to whack that priority valve way too often. I haven't been able to find a replacement.

 

[gimpyrobb]

This one?

http://www.eriksmilitarysurplus.com/prprva28pr.html

 

[glcaines]

Gimp, I owe you one! I've been looking for that valve for a long time. I called Erik several months ago and he said he didn't have any.

 

[gimpyrobb]

No prob. Its one heck of a price if you ask me!

 

[glcaines]

It's worth a lot more. Laying on your back in the mud, snow or rain and banging on that valve gets old very fast.

 

[gimpyrobb]

Where is yours located at? Most of the ones I have seen are on the firewall next to a T fitting over the motor.

 

[glcaines]

Where is yours located at? Most of the ones I have seen are on the firewall next to a T fitting over the motor.

Mine is located on the passenger side air tank facing the outside of the truck but up near the top. Fairly easy to get to when you need to bang on it. I'll have to see how easy it is to replace.

 

[Navo]

So the link that gimp posted is to the valve that is next to the air tank under the truck correct? If so, I'm gonna order one. I will have to post a picture of the one on my truck. This looks different? Maybe it's just me

 

[Navo]

Also thanks a lot Glcaines!! I'm gonna order that part listed above, and beat the crap out of the one currently on the truck. I'll also do the MM oil and let you all know how it goes. Thanks a bunch for all you guys input!!!!

 

[AceHigh]

Thanks Gary and Gimp! I spent a lot of time trying to figure this thing out when it happened to me. In addition to all the air tool oil in the air assist, I replaced the air regulator at the compressor and spent hours guessing and trying stuff.

Wish I could have figured out the $25 valve first thing! "It takes a village to own a truck"

 

[glcaines]

Navo, you are correct. My valve looks a little different from the one at Erik's. I'm going to call Erik today and make sure it will fit the A3. I'll let everyone know what I find out.

 

[m-35tom]

still sounds like a restricted line etc, unless air is escaping elsewhere. have soldier #2 listen for air leak.

 

[glcaines]

Navo, you are correct. My valve looks a little different from the one at Erik's. I'm going to call Erik today and make sure it will fit the A3. I'll let everyone know what I find out.

I just got off the telephone with Erik. The pressure protection valve Gimpy found for sale at Erik's is definitely the one that fits the M35A3, according to Erik. it is a slightly different design, but is the current replacement. Looking at the one on my A3, I believe it will be a simple task to replace it. http://www.eriksmilitarysurplus.com/prprva28pr.html . Erik told me that he has many in stock.

 

[rolling18]

I would like to piggy back on this thread with a SIMILAR problem.. only difference is I have a A2 with the aio-o-matic retrofit.
when starting for the day, builds pressure to 60lbs, bleeds off through vent on underside of drag link, builds up again bleeds off rinse and repeat cycle.. regardless of how much you steer or accelerate.

the odd part is. after driving if for awhile, it will suddenly let it build to 120 and STAY there!! and operate normally.

few days later, same thing happens. (I used to have the black aluminum regulator you mount up front in the frame but removed it.. no effect.

the drag link itself feels pretty loose and the seam toward the front with all the screws is loose BUT does not loose air when pressurized.
thoughts??

maybe this will help OP also..?:

 

[Navo]

I find all info helpful and hopefully it can help other later. I have not time to troubleshoot my truck. But when I do, Im gonna replace that air valve that was mentioned on this thread and also add mystery oil to the air assist cylinder.

 

[glcaines]

I would like to piggy back on this thread with a SIMILAR problem.. only difference is I have a A2 with the aio-o-matic retrofit.
when starting for the day, builds pressure to 60lbs, bleeds off through vent on underside of drag link, builds up again bleeds off rinse and repeat cycle.. regardless of how much you steer or accelerate. the odd part is. after driving if for awhile, it will suddenly let it build to 120 and STAY there!! and operate normally. few days later, same thing happens. (I used to have the black aluminum regulator you mount up front in the frame but removed it.. no effect. the drag link itself feels pretty loose and the seam toward the front with all the screws is loose BUT does not loose air when pressurized.
thoughts?? maybe this will help OP also..?:

Unfortunately, a lot of those air-o-matic units have been sitting around in storage for years before used and the seals dry out and potentially leak. I would recommend pulling the high-pressure air inlet for the system and put in a few ml of air tool oil and exercise the steering lock to lock repeatedly with the front end off the ground. Hopefully, this will rejuvenate the seals.

 

[Navo]

I found a thread located here on where to add Marvel Mystery Oil http://www.steelsoldiers.com/showthread.php?34591-M35A3-Owners-unite/page47 Do I need to disconnect any air lines or close any valves? Do I add the oil then reconnect the lines and steer back and forth? Or do I leave the lines disconnected and steer back and forth?

 

[glcaines]

I found a thread located here on where to add Marvel Mystery Oil http://www.steelsoldiers.com/showthread.php?34591-M35A3-Owners-unite/page47 Do I need to disconnect any air lines or close any valves? Do I add the oil then reconnect the lines and steer back and forth? Or do I leave the lines disconnected and steer back and forth?

You need to completely empty the air tanks first. You disconnect the air inlet line to the steering system and put the oil in there. Reconnect the line and re-start the engine. After tanks are full pressure, turn the wheel lock to lock over and over, with the front end off the ground. Hopefully, this will help.

 

[187]

Are you up and running yet? Hope you got our parts. Following this thread as a fellow A3 owner. Good luck!