M35A3 Owners unite

[rvnlrrp]

"Do you get any water or snot when you drain the tanks? "

Didn't get around to draining the tanks yet ( tomorrows job). I was so busy doing a my "happy dance" after getting the Truck running that I ran out of time. It really did my heart good when all that black smoke cleared up and it stated running clean. I will crawl under the Truck tomorrow and look at the air system, lines, etc before I get started and then bleed the tanks. I believe that is the problem. On my last tour as 1SG ( 1979), I had a great motor Sergeant, I really could used him now and now fully understand his value to the Army, and to Me.

 

[319]

"Do you get any water or snot when you drain the tanks? "

Didn't get around to draining the tanks yet ( tomorrows job). I was so busy doing a my "happy dance" after getting the Truck running that I ran out of time. It really did my heart good when all that black smoke cleared up and it stated running clean. I will crawl under the Truck tomorrow and look at the air system, lines, etc before I get started and then bleed the tanks. I believe that is the problem. On my last tour as 1SG ( 1979), I had a great motor Sergeant, I really could used him now and now fully understand his value to the Army, and to Me.

Read the TMs on the air system, and then crawl under the truck to get a good view of how the system is plumbed.

I know some folks will argue that you don't need to drain the tanks with the air dryer system, but I do, and mine are clean all the time.

 

[BIGDDV]

I was just thinking.......... (insert lightning bolts here..), and i'm begining to like this idea. Breaking the tire down, cutting the 3/8" pipe shorter, rethreading it, and then install the 3/8"F x 1/8"F adapter with the valve, this way it would not stick out so far, and without the elbow, it would not be likely to snag braches, small children, animals, or Volkswagens.

we bought the 90 degree kits from one of the military suppliers (can't remember which one) and eliminated the ctis completely. all wiring and hoses, fittings....everything. it is for sale and complete.

 

[BIGDDV]

Read the TMs on the air system, and then crawl under the truck to get a good view of how the system is plumbed.

I know some folks will argue that you don't need to drain the tanks with the air dryer system, but I do, and mine are clean all the time.

As a former trucker, I can tell you that every drier is different. I had one truck for 750000 miles and could go 3 weeks or more without draining the tanks.
had another one and I had to drain it every day.

 

[319]

As a former trucker, I can tell you that every drier is different. I had one truck for 750000 miles and could go 3 weeks or more without draining the tanks.
had another one and I had to drain it every day.

It's so easy to drain them, why not do it? Especially when you can buy the cable type drains for $8 each.

 

[glcaines]

I always drain the tanks on my A3 even though nothing ever comes out. It only takes a few minutes.

 

[rwoods]

I was just thinking.......... (insert lightning bolts here..), and i'm begining to like this idea. Breaking the tire down, cutting the 3/8" pipe shorter, rethreading it, and then install the 3/8"F x 1/8"F adapter with the valve, this way it would not stick out so far, and without the elbow, it would not be likely to snag braches, small children, animals, or Volkswagens.

While chasing down the source of an air leak, I remembered today why I went with the straight adapter - the two piece rim can be dismantled without removing it whereas you must remove the elbow if you go angled - just one more thing to make it simple for the tire shop. BTW my leak turned out to be the little stub pipe so I removed the CTIS and installed the adapter so I can get it fixed tomorrow at the truck stop.

Been working on my son's A3 and have learned lots from you guys. What to do and how to really screw thing up if not careful. Biggest issue was crappy fuel and stuck check valve on the return line. got that fixed and she runs good. Now got to learn about the air/compressor system. Seems the drivers side may have some sort of blockage as the CTIS doesn't inflate the tires on that side and the rear air line for trailer hook up does not supply air when the valve in opened.

Again, thanks for you advice.

On my front axle, I have air on one side and not the other. I have air at the back side of the hub but none on the other side. Theories here have ranged from separated inner lining of the air line to wrong wheel seal and/or bearing replacement. l have not been able to sort it out as I shredded the lining of my caroid artery (kind of like the first theory) and solo wrangling of an A3 tire and wheel, or hub and drum for that matter, is now off-limits for me. Seems odd that you would have all three axles out because as noted by others they run off separate air lines. Maybe your wheel valves are bad. I have one that will release at 45 psi when the system is running, but not when the system is off. If this is your case, you should be able to see and hear it happening. Otherwise to investigate, I would start in the rear and loosen the air line on the side that is not working at the wheel valve and see it any air comes out. If none, then I would loosen the air line on the back side. If air comes out then there then you know it is blocked somewhere in between, possible within the hub.

Hope you get it fixed, Ron

Ron

 

[glcaines]

In my opinion, regardless of whether you have the angled adapter that is stock or a straight adapter, anyone breaking down an A3 wheel is making a big mistake not replacing the valve stem grommet. These deteriorate with age and also tend to start leaking when they are disturbed when adding air via the schrader valve. These grommets are cheap and are responsible for almost all of the air leaks on an A3 wheel.

 

[187]

I have one right rear wheel that looses about 5-10 pounds of air per week. I'll have to try replacing that gromet. I haven't found anything with the CTIS yet leaking....Possibly the O-ring in the rim.

 

[glcaines]

I have one right rear wheel that looses about 5-10 pounds of air per week. I'll have to try replacing that gromet. I haven't found anything with the CTIS yet leaking....Possibly the O-ring in the rim.

You will need to replace the o-ring to get to the grommet, but I can almost guarantee that it is the grommet leaking. I would recommend replacing the brass nut as well as they tend to get rounded off. Make sure you torque the brass nut to 45-60 Lb-Ft when you replace the grommet. Don't use any sealant.

 

[rwoods]

In my opinion, regardless of whether you have the angled adapter that is stock or a straight adapter, anyone breaking down an A3 wheel is making a big mistake not replacing the valve stem grommet. These deteriorate with age and also tend to start leaking when they are disturbed when adding air via the schrader valve. These grommets are cheap and are responsible for almost all of the air leaks on an A3 wheel.

True true. I just wasted 3 hours at the truckstop. After explaining that the leak was at the grommet, showing them how to break the wheel down and helping break it down, they come up with we don't have a grommet that fits; I should have known better. Now I have a tire that used to go flat over two weeks with 80 psi go flat in 30 minutes. I have now ordered new grommets from Erik as well as a couple of the brass nuts.

Thanks for the useful posts.

Ron

 

[glcaines]

There is another thing that will help with the brass nuts. The nuts are slightly rounded and most sockets are rounded and they don't get a good grip. Use a 6-point socket. If you gring the outer edge of the socket all the way around to the point where you have a sharp edge, the socket will get a much better bite on the brass nut. With the sharp edges you can easily torque to 45 - 60 Lb Ft. I have now mis-placed my socket that I ground down and need to make another one.

 

[Deuce007]

I still cannot get my steering to stop setting off the low air buzzer whenever I turn. I have purged the air tanks, tapped on the CTIS manifold, turned the steering air supply valve open and closed, and listened for any leaks but no matter what I do I still can't figure out why it makes my psi gauge jump everywhere between 45 and 120psi which always causes the low air buzzer to sound. I cant just ignore it because whenever I am pulling my m105a2 it causes the brakes to lock up. I can leave the air supply unhooked from the trailer so that they don't lock up, but I would like to have it hooked up for heavier loads. My only thought is that the air tank that is closest to the passenger side always seems like it only has a very small amount of air in it when I drain it but I don't know if that even relates to the steering problem.

 

[Hoefler]

Both my trucks (A3) have air pressure drop from about 120 to 90 when turning. The pressure comes right back up after turn. Sound like maybe your air cylinder is leaking.
Feel the discharge air ports when having someone turn the wheel. These are on the bottom of pitman arm. Exhasutr air comes out of the two hoses that join the duct that runs to intake.
I just had a sporadic leak on my air regulator that feeds the steering. It casued my air guage to drop to zeo though I am uncertain why. Made the steering hard to turn.
I simply removed the regulator and reconnected air pressure line (new tube section). Sterring is now back to normal and steers even better. I will be putting in a new regulator even though I had it set at max.
Pete

 

[AceHigh]

I still cannot get my steering to stop setting off the low air buzzer whenever I turn. I have purged the air tanks, tapped on the CTIS manifold, turned the steering air supply valve open and closed, and listened for any leaks but no matter what I do I still can't figure out why it makes my psi gauge jump everywhere between 45 and 120psi which always causes the low air buzzer to sound. I cant just ignore it because whenever I am pulling my m105a2 it causes the brakes to lock up. I can leave the air supply unhooked from the trailer so that they don't lock up, but I would like to have it hooked up for heavier loads. My only thought is that the air tank that is closest to the passenger side always seems like it only has a very small amount of air in it when I drain it but I don't know if that even relates to the steering problem.

I had the exact same problem, started out very rarely, became worse over time until it took about 5 minutes to build air at start up, then I still could not drive as turning the wheel set off the buzzer. Did the air tool oil routine, no joy.

Finally I went under the truck with a hammer, started trying to find where the air was going. I hit a regulator-like device near one of the air tanks and it made a long funny noise, and suddenly everything started working like a new truck.

I don't know just what I did or why it worked, but it worked. BTW I went under and did this when the truck was first started and would not build air. I knew the air had to be going somewhere.

 

[Deuce007]

Ok, I will try looking again for a leak tomorrow when I have someone turn the steering wheel while I look for leaks. Like AceHigh mentioned about the oil method, what would prevent the oil form traveling through the air lines to the air dryer and ctis manifold?

 

[Deuce007]

OK, I just ran out to the truck because of about four times of reading the other post I realized exactly what was leaking. It is an obvious leak in the large hose that connects the two exhaust hoses of the drag link with the intake. I always knew that that hose had a leak but I never knew that it was connected to the intake, I just thought it was hooked up to the engine exhaust. so now I just need to find someone parting out an a3 to fix it right?

 

[glcaines]

You only put the oil in the input side of the steering actuator. This lubricates the seals in the acturator as well as the main cylinder. It works better if you jack the front end up and work the steering wheel back and forth from lock to lock about 20 times to thoroughly get the oil to the seals. I still had a slight problem, but it continued to improve over the next few weeks.

 

[AceHigh]

OK, I just ran out to the truck because of about four times of reading the other post I realized exactly what was leaking. It is an obvious leak in the large hose that connects the two exhaust hoses of the drag link with the intake. I always knew that that hose had a leak but I never knew that it was connected to the intake, I just thought it was hooked up to the engine exhaust. so now I just need to find someone parting out an a3 to fix it right?

I could be wrong but that leak does not matter at all. In my A2 with air assist steering those hoses do not exist and when I turn I get a real cool "whoosh". I am betting you can either tape that hole closed or just cut the hose in two and seal off the part going to the air cleaner.

 

[glcaines]

AceHigh is absolutely correct. That hose only handles the exhaust side of the actuator. If air is continuously leaking from the large hose, that means that air is leaking from the air assisted steering past seals. The only air that should enter the large hose is air that is released when the steering wheel is returned towards or to the neutral position.

Try putting MM oil or air tool oil into the input side of the air actuator and see if that helps. There are many posts on SS regarding this. It quite often helps and is a lot cheaper than replacing parts with take-off parts or NOS parts, which are likely just as old as what you already have on your truck.