hyd problem

[pete49]

I have a problem with a piston pump on a 601. The 3 point pulsates as it raises.it does not hicup but tiny little pulsatining.I know you guys have seen every little symtpton,maybe you could help me pinpoint this problem.i have taken the pump apart twice and every thing looks good.do any of you have a easy way to replace the ball seats in these pumps?thanks

 

[RickB]

Weak or broken check ball or piston spring, foreign matter between ball and seat. Not enough patience in bleeding the pump. I have seen pumps hold a slug of air in one piston chamber quite a while before burping it out. I cheat with the seats, I have access to the Nuday tools to extract and install them. I have heard of guys tapping threads in the seats, screwing a bolt in them and pulling with a slide hammer. That should work well if the seats aren't too hard.

 

[Ultradog MN]

I have a 3000 but had a similar problem last winter. Was using the loader to remove snow and hit the curb with the bucket. Loader is plumbed off a remote valve and uses the tractors onboard pump.
The hyd line from the valve started chattering, pulsating and would barely raise the loader.
I had the lift cover off looking at all the check valves, seals etc. Put it back together and it still would barely raise.
Then an older fellow I know stopped by, took one look at the chattering and said its your pump.
I had a spare pump which I put on and it cured the problem.
I'm no hydraulics expert by any means but I did learn this:
Make yourself up a tester with 3000 psi guage and a hyd hose. Screw into your remote valve if you have one. If you don't have a remote valve you will have a blank cover with a test port on it. Under your seat.
I think you should be developing about 2000 psi.
If not and your pump is chattering you will need to rebuild your pump.
I could have saved myself a lot of wrenching if I had only taken the good advice I got here and built a tester.
I just looked at the parts here at YT and a rebuild kit for your pump is $35 + shipping.
Good luck.

 

[pete49]

Thanks guys Ill try your suggestions,good ideas!

 

[BobH in WI]

Ultradog - what is the approx. cost to build a tester? Also, Recommended parts and sources etc.?
My hydraulics are still on the "fritz" and if I can build a tester for a reasonable price, I think that would be a good starting point.

 

[Ultradog MN]

I just looked at guages on Northern's website.
Looks like this one would work just fine.
All you really would need is a guage like this one and whatever fittings would be required to screw it into your test port.
Worst case, you might need to put like a 12" piece of hyd. hose on it. Doesn't have to be fancy. But just like you can't see those volts or ohms in a wire without a guage, you can't SEE hydraulic pressure.

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