Pulling pump AGHHHH!!! D200

[coldone 35]

WHy Oh WHy did they put socket head cap screws on the &&$@#$%^ manifold!

[Sparky-(Admin) 19,550]

Umm...I can offer no advice other than good luck with getting them out . I remeber the first time I removed a "D" series tranny...not a fun task.

Mike...........

[Kelly 1,028]

If I remember right I used a Allen socket with a long ext. and a 3/8" ratchet, I think I got 3 of them that way.

[coldone 35]

I finally got it out. The PTO center shaft bearing was in the way,had to take the screws out and move it down the shaft. I have the 5/16 allen socket but its the short one, Picking up a 6 inch one tonight. Valve plate is shot, cylinder block is grovved just as bad. Pics later.

[1maidenfan 201]

Ouch, that doesnt sound like fun. How did you realize something in the pump was bad? Symptoms :eusa-think:

[coldone 35]

I new that teh rearend blew up in it (original problem) then discover the hydro motor was messed up. That was the first installment of my post about lapping the valve plate. Once I got the motor sorted out I was still having problems with lack of power and heating up of the tranny oil. So I figured there was problems in the pump also. I picked up a used pump (stripped splines) and a used hydro motor on ebay over the last few months and have rebuilt them. I am going to install both on the tractor then rebuild the originals so I can have spares.

More later Gotta take Hunny bunny and the kids out tonight.

[JamesBe1 80]

Hahaha. I know how you feel about how they attached the pump to the manifold. The first time I did it was really painful. It's only gotten slightly less painful with the numerous times I've had to do it.

Don't forget to make yourself some alignment pins for when you put it back together.

Oh, and maybe have a spare set of backup orings (the square-profile ones). I have damaged or lost one or two on reassembly, and ended up waiting a few days for new ones to arrive. Sorta takes the wind out of your sails when that happens.

Good luck and take plenty of pics.

[coldone 35]

Ouch, that doesnt sound like fun. How did you realize something in the pump was bad? Symptoms

The symptoms of a my bad hydro were:

1: Lack of power

2: Tranny oil temp got high fast, mowing one slightly hilly acre on a 90+F day the temps would be almost to the yellow when done

3: Power dropped of dramatically with temp rise. It wouldnt hardly pull itself up a hill.

4: Speed not staying constant when going from down hill to uphill, not even close.

5: Lack of dynamic braking

6: Could push with push valve closed

7: Slight change in engine sound (bogging down) when under load.

8: Wheels would stop turning with TCL in full for/rev position and engine would only change tones slightly

9: Pressure test did not meet specs of manual ( cant remember exact readings)

All of the above were after I had went through the hydro motor and lapped the valve plate.

Before I went through the motor the symptoms were:

1: No power. It wouldnt even pull itself up a slight incline. Couldnt even get over roots that were above the ground

2: Hydro pressure test, could hardly make 25PSI at idle. Less than 350PSI on lift cylinder full extension test.

3: Heated up oil Very fast

4: No bogging down of the engine with TCL full for/rev and wheels would not turn under the slightest load (up an incline)

I am pretty confident in saying that if the hydro motor valve plate shows scoring, then the pump will show it also. Mine had major scoring in both. In my original motor, the valve plate thickness after lapping was 0.147 inches. I didnt measure it before I lapped itbut the other 3 valve plates that I have measure 0.156. So I would assume that the original valve plate had been scored to 0.009 deep. Not to mention that the cylinder block was also scored, not as severly but still scored. I would estimate that the combined scoring would have been more than 0.012-0.014.

By lapping just the motor valve plate I did regain some usefulness to the tractor. I have used it as my main mower for this season and I have used it with a homemade scarifier to groom my driveway. It was limited in its capacity by the damage in the pump. I wouldnot hesitate to pull the hydro motor off and lap the plate and block if I were having trouble with lack of power. At least you would regain some measure of usefullness.

Hope I answered your questions, I can get carried away.

[1maidenfan 201]

:bow-blue: :bow-blue:

[pfrederi 17,147]

WHy Oh WHy did they put socket head cap screws on the &&$@#$%^ manifold!

I think if they used a hex head bolt there wouldn't be enough clearance between it and the pipes for a socket wrench. Sure wouldn't want to try a open end or crowfoot up in there. Big time support for the suggestion of making aligning pins, also some grease to keep the o rings in place. The job is a PIA having the rear PTO shaft just adds to the fun.

[coldone 35]

Rebuilt pump is all assembled, aligning pins made, just gotta make a sealing washer and I will start putting it back together. Got the 6 inch long 5/16 allen socket last night, hope it makes it easier.

[coldone 35]

Well Its all back together minus the hood. Filled it up with oil, raised the back tires off the ground, started it and purged the system. Dropped it down and took it for a test spin. WOW what a difference. I checked it like I was mowing with it and there is only a slight difference in up speed vs downhill speed. I put my homemade scarifier on it and backed it up to a stump, full reverse the tires will now dig a hole up to the transaxle. Slamming on the brakes will now lock the tires, Full forward, from a stand still, will spin gravel (tires are loaded). My pressure gauge is busted so I cant take pressure readings but I believe that it is almost as good as a new pump.

[midnight rambler 36]

stick a long allen wrench up from the bottom and use the boxend on the top, easiest way i have found

[JackC 616]

Now there is an accomplishment. Congats on that.

Sounds like the pressure test is a good way to test the overall health of the hydro.

Any ideas on how it got as bad as it was, lack of clean oil, excessive use, all of the above?

[coldone 35]

Any ideas on how it got as bad as it was, lack of clean oil, excessive use, all of the above?

The differential busted and sent metal particals throughout the hydro system. The pickup screen is only good for large particals. This caused the scoring on the valve plates and cylinder groups of both the motor and the pump.

Thank you.

[1maidenfan 201]

Well Its all back together minus the hood. Filled it up with oil, raised the back tires off the ground, started it and purged the system. Dropped it down and took it for a test spin. WOW what a difference. I checked it like I was mowing with it and there is only a slight difference in up speed vs downhill speed. I put my homemade scarifier on it and backed it up to a stump, full reverse the tires will now dig a hole up to the transaxle. Slamming on the brakes will now lock the tires, Full forward, from a stand still, will spin gravel (tires are loaded). My pressure gauge is busted so I cant take pressure readings but I believe that it is almost as good as a new pump.

of your beast tearing up the ground

Can you explain what and or where the "alignment" pins go?

My D 160 slows going up hill till it reaches the top then picks up to the speed its set at, any idea on this ?

Thanks.

[coldone 35]

Can you explain what and or where the "alignment" pins go?

The alignment pins are used when reinstalling the pump. They take the place of the 3/8 hex head bolts and allow you to set the pump into the manifold and have it aligned so that you can install the two cap head bolts without much fuss. The working space is very limited and the pins made all the difference in making it easy to install the bolts. Once you get the two cap head screws in, you remove the alignment pins/screws and install the final two bolts in the manifold. The directions for making them is in the manual.

My D 160 slows going up hill till it reaches the top then picks up to the speed its set at, any idea on this ?

Thanks.

I am jaded so my first guess is the valve plate. The easiest one to get to would be the hydro motors plate. I would remove the motor and take it apart to see the condition of the valve plate. If there is any scoring on the plate, you will be bypassing high pressure oil to the low pressure side. It could also be that the retaining/preload system in either one of the cylinder blocks system could be malfunctioning and not able to hold the correct preload on the assembly.

Pics and operational vids will be coming in the next few weeks.

[JamesBe1 80]

Coldone, you are now officially the dysfunctional D family expert on hydro systems! I tip my hat to ya!

BTW, I think it might be worth mentioning that the alignment pins are really just 3/8" bolts with the heads cut off. Two or three inch long should be long enough. Just screw them into the pump and they will stick through the holes in the manifold plate where the bolts normally go. Oh yeah, it helps a lot to cut a screwdriver slot in the bottom of each of them so that you can use a screwdriver from underneath to screw them out.

[1maidenfan 201]

Thats some great info guys!!!!

I agree that COLDONE is definatly the hydro master. :bow-blue:

[coldone 35]

Nope no master, just too dumb to know they cant be fixed.

[JamesBe1 80]

Nope no master, just too dumb to know they cant be fixed.

Yup, I hear you. I have a touch of that in me too. Also, I am pretty cheap. Add to that the fact that I despise planned obsolescence, and I am the perfect storm of always fixing something.

Still, I have to admire your efforts and your willingness to share your learnings with us. There's no telling how many good pieces of old iron you have saved from the scrap heap.

[1maidenfan 201]

Nope no master, just too dumb to know they cant be fixed.

Yup, I hear you. I have a touch of that in me too. Also, I am pretty cheap. Add to that the fact that I despise planned obsolescence, and I am the perfect storm of always fixing something.

Still, I have to admire your efforts and your willingness to share your learnings with us. There's no telling how many good pieces of old iron you have saved from the scrap heap.

I agree with you 1000% and cant say enough on how helpfull REDSQUARE is. :bow-blue: