Steering problems!

[bombi275]

We just got a M818 dump truck at work which we aren't to familiar with and soon found out this was the place to go with questions. The other day the steering just quite turning to the right, it would turn left just fine, but when turning back to the right it would stop in the center as if it had hit full lock. We unhooked it at the pitman arm and the power assist ram and it turned both directions just fine, no binding or rough spot. When we hooked it back up we noticed when it stopped in the center, the power steering pump would start slipping on the belt. We removed the power steering pump and upon disassembly noticed the spring on the pressure relief poppet, I think, was broken in 2 places. I have been looking for a week for a make and model number for this pump so that I can order a new seal kit and spring, but can't for the life of me figure this out. Any help would be greatly appreciated. Thanks again.

 

[porkysplace]

Welcome , if you don't have TM's they free to download at ; www.jatonkam35s.com or
www.liberatedmanuals.com . You may want to search the classifieds for a used pump or maybe e-bay.

 

[bevanet]

It really doesn't seem like your pump would cause it to stop turning in a particular spot (center) did you raise the front wheels off the ground and see turns freely both directions without the engine running? if it catches or gets harder to turn at the center? Seems to me that something is binding up and this causes the pump to build up pressure and then the belts to slip. If you found a broken spring though - might as well fix it. Also a dump is typically an 817 and a tractor is an 818.

 

[bombi275]

I never expected reply's this quick, thanks guys, this place is great. I am going to download the TM's right now. I did not jack up the front of the truck and try to turn the wheels, I realized this after I removed the pump of course, like an idiot, then I found the broken spring and figured I better fix it before I put it back together. I just don't know where or what kind of seals and springs to look for. I can't find a manufacturer name or number anywhere on the silly thing. I also thought it should be a M817 but the data plate says M818.

 

[porkysplace]

Memphis Equipment should have what ever you need ,but they can be pricey .

 

[MyothersanM1]

I also thought it should be a M817 but the data plate says M818.

Maybe the former owner slapped a dump bed on an M818. The M817 Dump and M818 Tractor are the same frame and wheelbase.

 

[R Racing]

First how tight are the belts ? They need to be tight. Second how much fluid is in the unit ? if its low the pump will lock up. Third and very important when you turn the wheel on the truck you may not know but you are screwing the shaft in and out of the gearbox about a 1/4 inch in each direction . so the steering shaft has to be able to float to alow this to happen . If the steering colum is to far in it will steer fine to the right but wont to the left , because the valve isn't allowed to travel out far enough to move fluid to the oposite side of the valve. if this is the case you need to loosen the steering colum. 2 each 9/16 bolts . 1 at the floor. 1 at the dash. and pull the colum back towards the back of the truck about 1/2 inch.

 

[R Racing]

Also E bay has rebuild kits fairly cheap.

 

[M813A1]

Also consider that someone before you could have had taken the pitman arm off and when they reinstalled it they could have gotten installed in the wrong position !! With the truck front end on jacked and on jackstands .. Check your total travel with the pitman arm installed and then try the travel without the Pitman arm off and see if it is centered properly on the gearbox..

 

[R Racing]

The steering box has a alignment mark to the pitman arm so u can look at that if indeed someone had it off.the center splined shaft has a line in it that lines up with a line in the arm. if you have ever removed 1 its not a easy task. they have a 2 3/8 nut that when installed presses the pitman arm onto splines. to remove the pitman arm you would have to use heat and a sledge hammer and to beat the arm loose .

 

[bevanet]

I've bought several small parts from white owl trucks.

 

[papabear]

I'm afraid you will need to replace the steering gear assy.

Troy had the EXACT same problem with his 5ton dump. He got the takeout gear from AMGENERAL here on SS and fixed the prob.

I have to admit, it was kinda fun moving the truck around and then trying to get it back on line making ONLY right turns

 

[Robo McDuff]

I'm afraid you will need to replace the steering gear assy.

Troy had the EXACT same problem with his 5ton dump. He got the takeout gear from AMGENERAL here on SS and fixed the prob.

I have to admit, it was kinda fun moving the truck around and then trying to get it back on line making ONLY right turns

Have a look at this thread. What I read here looks too familiar with what I have. I will jack up the wheels tomorrow and check again, but I am afraid it needs a new gear.

One thing I was thinking of. If the adjustment screw has been too loose too long, can it be that the lever has slipped over the cam?

I checked the TMs. and the ...34-2 has a steering gear that looks different from mine, and in the TM ...35, the picture is black, nothing visible, like almost all the other pictures on the steering (and on everything else $%$@@#$).

The drawing some pages further (page 151, image 120.1) looks exactly like my steering box. Is that the Ross HP70?

Did Troy take the steering gear apart after replacing it to see what was wrong? Any pics on the replacement and the damaged box?

 

[R Racing]

Here is a link to how to replace the steering box in a 5 ton m809.

http://www.steelsoldiers.com/5-ton-up/62792-replaced-steering-box-5-ton-today-series-m809.html

 

[dozer1]

Any updates on this bombi275? I would like to know if you overcame the problem and what the offending component was for sure. Got a 817 myself and ya never know whats going to turn up in the future.

 

[Robo McDuff]

Here is a link to how to replace the steering box in a 5 ton m809.

http://www.steelsoldiers.com/5-ton-up/62792-replaced-steering-box-5-ton-today-series-m809.html

I saw that one already. Should have repeated that I have am working on a M51-A2. Unfortunately, the location of the steering house and the way its fixed (and probably everything else including types) in that M809 thread differs from the situation in the M39 series, or at least in my truck.

This is when being in Europe is - again - definitely a disadvantage. I cannot take part of the main discuusions in real-time because I am 6 hours or more in front (and asleep).

 

[Robo McDuff]

Pics will come tomorrow, but here is what happened.

Already last year, we had tried to tighten the adjustment nut without any success on the free play. Today, we took off the front wheels, and kept turning the steer first without engine and later with engine running. More and more free play!?

We kept playing and messing and then I finally noticed that when pulled very hard, it was possible to pull the pitman arm outward about 3 mm (0.1 inch?). Still, adjustment did not work. Then we just moved the pitman arm in and out and then with one person hanging on it (pulling it outward) the other one adjusted the nut much deeper, till the arm finally had only a fraction of play. It looked like the entire free play was at least significantly less.

This may be a problem of just everything beeing stuck in old grease etc. Keep playing and turning and adjusting for a while to see if that works. But one person alone just by hand trying to adjust the nut softly againt the pitman arm did NOT work.