Power Steering Pump Repair Kama 554

[3RRL]

You may have seen some of the work I've been doing with the Kama 554 these last couple weeks around the homesite and especially the road work in my Log Home Thread. Well, my power steering had been acting funny for some time now. Sometimes working just fine and other times it gets really hard to turn the steering wheel. I did the usual inspection, checked for leaks, checked the fluids and filter, checked the cylinder and all the banjo fittings etc. to see if any of that affect it. But I saw nothing to indicate any problems.

I kept working the tractor even though it was hard to steer when suddenly I lost ALL steering. I had just checked and added fluid too. The steering wheel just spun around not moving the wheels. I had to get it to camp and used the steering brakes to navigate the winding dirt road.

When I got back to camp I opened the hood and noticed the lower left side of radiator and surrounding area was covered with hydraulic fluid. I checked the steering reservoir and it was empty, so I figured it sprang a leak somewhere. I filled the reservoir a little, started the Kama up and worked the steering wheel to see where the leak was. There was a small stream shooting out towards the radiator from the bottom of the power steering pump.

 

[3RRL]

The stream was coming from the bottom and I could tell it was coming from that round black socket head cap screw that is bolted directly below the high pressure out line, on the bottom of the pump. Of course I could not tell it was a socket head cap screw yet. I had to get a mirror to see since the pump sits on a slight angle inwards. Not only that, but the loader frame up there was in the way too, so I couldn't get an Allen wrench in there as it was.

I decided to take the pump off so I could get to that black screw. Well, that's not as easy as it sounds. I found there was very little room between the radiator fan shroud, the alternator belt (which Larry and I just changed) and the engine block. To get in there and swing a wrench to loosen the pump bolts, I had a choice of removing the radiator or trying it by removing the alternator. I chose the latter.
You can see Loretta holding the alternator. See the belt, fan shroud and where the pump body is. There are 4 bolts to remove and the 2 inside ones are a pain to get to to swing a wrench in there.

 

[3RRL]

I had already removed the suction line and also the high pressure line, so I considered myself lucky when I got all the bolts out and loosened the pump. I slid it forward to get it out of there and guess what ... the pump hit the radiator fan shroud and the pump shaft was still in the drive mount. Crap!
I decided to rotate the pump instead so I could get to the bottom and that worked out.

Here is a photo of the socket head cap screw I had to remove. The leak came from between the cap screw and the pump body. I was hoping it was not a crack.

 

[3RRL]

I removed the cap screw to find the rubber coated washer, known as Dowty seals or Stat-o seals had a tear on the side where the leak was.
Here are a couple close ups showing the bad seal on the bottom of the first photo and then on the top left in the second photo.



I cleaned of the pump body and inspected it to be sure there were no cracks in it and it was fine. So the leak must have come from that tiny tear in the seal. But I was at camp and about 1500 miles away from Chip to get replacements for that Metric seal.

Not only that, I looked inside the body and saw a threaded plug with a small restriction hole in the center, but it was just rolling around in the hole, not threaded into it's place! That must have been the restriction I felt every once in a while when it was floating around plugging up the flow. I also found a couple slivers of steel that looked like chips inside. They also could have caused the problem.
Anyway, I screwed it back where it belonged inside that hole.
Here's a couple shots of that restrictor plug.



My next problem was how to fix that rubber covered washer so I could get back to work.

 

[3RRL]

Now I was ready to reassemble the cap screw if I could get a rubber coated washer.
Not having a replacement, I took a razor blade and cut all of the rubber off the washer and cleaned it up good. Then I got my Harbor Freight Metric "O" ring kit out. I found a skinny "O"ring that fit inside the washer and was about .020" thicker than the washer. It also fit nicely around the threads of the plug.

My thoughts were if I could get that "O" ring to stay inside the washer when I put it over the plug, it would seal perfectly. The "O" ring would squish down to seal and the washer would keep the "O" ring from getting blown out. The washer acted like a counter bore for a ORB fitting and the repair worked perfectly. How lucky is that?

Here is the "O" ring and washer repair I made. In the first photo, you can see the steel washer in my right hand and the "O" ring around the threads of the plug in my left.. The second photo shows how the steel washer fits around the "O" ring and plug, making like a counter bore for the "O" ring.




So that's it.
I bolted everything back together and filled up the reservoir to try it out ... perfect... no leaks. Guess what, the steering works great now without intermittent hard turning like before.
LOL ... Another perfect job done in record breaking time.

 

[greg_g]

I admire your field expedience Rob. I read with interest to see if any of your descriptions might help me figure out the perenniel steering problem with mine. Unfortunately not, but it was an interesting read. Good job.

//greg//

 

[Diamondpilot]

Nice job on the field repair. I learn a lot from your post. I like it that you can look outside the box to figure things out and get it up and going again.

Chris

 

[3RRL]

Thank you Greg and Chris.
Making field repairs is so important for me since I'm in a very rural area of CA and of course, no Chinese Tractor dealers nearby. My "camp" workshop has almost as many goodies as my home garage shop. So I am very lucky to have some supplies that can be substituted for the original part.

Greg,
I know you've been suffering similar steering problems with your Kama. I'm wondering if that little set screw plug ... the restrictor might have worked it's way loose inside your pump? It screws in from the bottom, directly below the high pressure outlet so it seems to be a flow restrictor because of the small hole in it. If that is loose and floating around like mine was, it could lead to erratic steering behavior. I don't know for certain if that was the cause, but I ran my Kama for at least 6 hours after the repair and all that went away. I even refilled the reservoir with AW32 instead of AW68.
I have 466 hours on the meter now.

 

[greg_g]

Greg, I know you've been suffering similar steering problems with your Kama. I'm wondering if that little set screw plug ... the restrictor might have worked it's way loose inside your pump?.

I've had a hot weather steering problem since the tractor was new, but the symptoms are nothing like yours. And there's nothing erratic about mine, it's strictly temperature related. You even demonstrated the difference by being able to drop from AW68 to AW32. The only way to fix my hot weather problem is to go the other direction - all the way to AW220 (about 50W) during the summer. AW32 works just fine the other three seasons.

//greg//

 

[3RRL]

I wanted to revive this thread to report that the first 50 to 75 hours I had perfect performance after the repair.
But I have had on and off, good and bad performance out of mine since then. Exactly like the old symptoms, not like the power steering failure from the leak. I have 560 hours on the Kama now! Every morning the steering works like a charm ... smooth and free and light to turn the wheel. Goes lock to lock forcefully (positively) and holds, even under a heavy bucketful.

As it gets hotter, it gets harder and harder to turn like you've lost the power steering altogether. Then at some point it's like it "gives way" and starts steering light again, like the power steering kicks back on. So I don't think it's the cylinder bypassing or it would be bad all the time. And it wouldn't feel like a clog passed through, know what I mean? I run AW68 fluid in mine too (again). Fluid level is good and suction strainer is clean. I think it's debris that gets caught in the steering valve or somewhere.

After the repair, it must have left some remaining debris like part of that grommet in there that the strainer is not catching. So now it is back to the same old thing. Works good when first started and then when it heats up it stops working good. Then on occasion, it feels like a clog passes and starts to work good again, and then not... Larry told me he put a 10 micron filter on his steering system return in addition to the suction strainer, and I may do that too. Might help with this recurring problem I seem to be having.
Any thoughts?

 

[dfkrug]

After the repair, it must have left some remaining debris like part of that grommet in there that the strainer is not catching. So now it is back to the same old thing. Works good when first started and then when it heats up it stops working good. Then on occasion, it feels like a clog passes and starts to work good again, and then not... Larry told me he put a 10 micron filter on his steering system return in addition to the suction strainer, and I may do that too. Might help with this recurring problem I seem to be having.
Any thoughts?

Maybe that flow restrictor plug came loose again. Did you use Locktite?
Or maybe a tiny bit of debris is blocking that hole?

 

[greg_g]

First thought is, that Larry doesn't have a separate steering pump. At least I don't think he does. Anyway, adding a second filter to an independent PS circuit sounds to me like overkill. I mean, consider the numbers of POVs that have no power steering filtration at all.

I have yet to disassemble my steering pump, I'm waiting for the winter slowdown. But I've never experienced this hard steering issue correct itself either. My only remedy to date, has been simply to let it cool down - then go back to work.

My second thought - shudder - is that it might be in the steering controller. But I hate to think of the disassembly required to get that bugger out. I still think I'm going to tear down the pump first, then go from there.

You may have a hose breaking down internally. Debris from the decomposition could be causing intermittent blockage through your steering pump/relief valve.

//greg//

 

[3RRL]

Maybe that flow restrictor plug came loose again. Did you use Locktite?
Or maybe a tiny bit of debris is blocking that hole?

Yeah, that's a possibility ... I didn't use locktite to secure that restrictor.
Shees, I was trying to get out of doing another dis-assembly. Thinking about it though, if I do install the filter, I might as well take it all apart again and clean everything up.
I was hoping to add the filter and shazam ... everything is fixed.

 

[greg_g]

I was hoping to add the filter and shazam ... everything is fixed.

Just outa curiosity, what's wrong with the filter that's already installed? Or am I missing something here?

//greg//

 

[3RRL]

Just outa curiosity, what's wrong with the filter that's already installed? Or am I missing something here?

//greg//

I'm thinking it's a strainer in there and not a 10 micron filter.
I could be mistaken though. What's on your 454?

 

[greg_g]

I'm thinking it's a strainer in there and not a 10 micron filter.
I could be mistaken though. What's on your 454?

There's 80x80 mesh in the main (rear) hydraulic sump strainer, yes. But that's got nothing to do with the steering. I'm talking about inside your power steering reservoir up front Rob. Don't know how many microns, but it's definitely no strainer. Appears to be about the same porosity as both the oil and fuel filter cartridges

//greg//

 

[GuglioLS]

Hi Rob,

Steering problems seem to be popular these days. My power steering was behaving badly too, as if I had zero power steering, you know, power steering by Armstrong? It started several months ago. Turning to the left was a little tough, but to the right, forget it. Mine was not intermittent. I replaced the steering valve (Steering machine as Jinma likes to call it) that made no difference. (BTW replacing the steering valve was easier than removing the pump). I finally replaced the steering pump altogether and that fixed the problem. After taking the old pump apart I discovered there is a pressure relief bypass valve built inside the pump. I suppose I should have tried adjusting it, but too late, I already had the new pump installed and was not about to put the old one back in to experiment with adjusting the relief spring.

My Jinma 354 has it's own separate power steering pump and reservoir, a completely separate circuit from the TPH / FEL / TNT / Grapple etc... Just like yours.

It has about a 2 quart fluid reservoir and no suction strainer. In order to get the darn pump off I had to drain the radiator because the petcock was in the way of removing the pump. After draining the coolant and removing the petcock I was able to get the steering pump off. It was a real PITA. As you mentioned I did install a 10 Micron return filter, all I did was cut the rubber hose between the hard line and the tank and insert the filter between the two. Works like a charm now.

My gut feeling on yours is the "W" o-rings on the ends of the inside of your pump are flat, so your pump is not building up enough pressure. OR like you said there is crud circulating around in there gumming up the works. OR you may need to simply adjust (turn in) the bypass valve to get more pressure.

I could take some pictures of my filter mod if you like. It's just a simple spin on Northern tool or Surplus center 10 micron hydraulic return filter with some brass 5/8" barbed hose X 3/4" male NPT fittings (From Home Depot). I think it was a worth while $16.99 investment to protect a $189 pump, a $ 280 steering valve and a $200 steering cylinder.

Surplus Center Filter

Does your pump have an adjustable internal pressure relief bypass valve like mine does? If so have you tried to adjust it?
When your steering works and you turn the wheel all the way to the stops and beyond, can you keep turning the wheel? How much resistance is there if you can keep turning the wheel? The reason I ask is if there is little resistance when turning the wheel past the stops, the bypass in the pump is set to low. That's how mine works anyway.

Larry

 

[greg_g]

Rob and Larry, this might help. Whereas the three of us have independent steering circuits (thanks for clarifying that on yours Larry), it sounds like there are some profound differences between the KAMA and Jinma designs. First, note the canister filter in the steering sump assembly (28). From my perspective, the fact that it's a paper cartridge classifies it as a filter rather than as a strainer. Note the round disc with the holes in it just above the reservoir. If pressed for a part name, I'd call that a strainer.

Second, there are no rubber lines in which to insert a strainer fixture. The only flex lines are in the cylinder supply/return path (12). There's a rubber coupler (26), but no usable gap between the steel lines underneath. It's strictly an anti-vibration device like the cylinder flex lines . Third, note the steering controller (what Larry calls his steering valve). On mine, removal is effectively blocked by the fuel tank frame. At first glance I can't see how my steering controller could be removed without first taking off the entire dash/instrument panel, the fuel tank cowl, the fuel tank. and the tank frame.

Earlier in this thread, Rob too encountered a pump removal clearance problem, stating that either the alternator or radiator cowl had to be taken off first. Wouldn't have to on mine, but his 554 has one more cylinder than my 454. So I'll concede a possible pump clearance issue. But given the choice, I think I'd rather remove an alternator or radiator cowl, than an entire dash and fuel tank.

So basically what I'm saying, is that the addition of an aftermarket hydraulic strainer on a KAMA seems redundant. Pretty sure KAMA bolted the same steering system on both the 454 and the 554, which means that you should already have both a filter and a (coarse) strainer Rob.

I'm still going with the pumps internal relief valve as being the culprit (on mine at least). But unfortunately I can't afford the tractor downtime this time of the year to validate that assumption. I'm just countering the situation with 50W fluid, until such time as I can get the pump on the bench. Then perhaps I'll be able to assist with the question whether or not the relief valve is adjustable. Alternatively - since my TS354 and KM454 have pretty much the same steering system - I could swap pumps and see if the hard steering issue follows the pump. Either way, it's going to have to wait for either winter - or a steering failure - whichever comes first.

//greg//

 

[GuglioLS]

Real quick - here are a boat load of pictures of my add-on power steering hydraulic fluid return filter. And some of the hydraulic steering pump I had to replace. I will describe in more detail later as the door is about to hit me in the 8$$ on the way to the airport. The Jinma tank is just a tank no filter no strainer, it does have a screen on the fill port for when you pour in brand new fresh fluid








Larry