I think I lost my hydro pump on my JM 354

kbone1 · Feb 11, 2006

Well I did it, and I know this was my own choice, I was kind-of weary of using
Kero to flush the Hydro system. I made the assumption (my first mistake) that the
factory manual and the info from this site and others was the best way to go. My thoughts were that Kero does not have enough lubricity for the tight tolerances in the hydro system, but hey, I'm tractor and hydraulic stupid. This is my first tractor, so I am still learning how it operates and how to use this thing and it has been great until now. The info I have gained from this site and others is wonderful, don't get me wrong I am not pointing fingers; I know this is something I chose to do. OK, enough ranting!! I need help in a major way! The trans and drive train flush went well a couple of weeks ago, so this weekend I figured I would tackle the Hydraulic system. I drained out the old fluid and it was very milky colored, probably water contamination. I kept my ZL-30 FEL connected in the system, put about 2.5 gallons of Kero in and cycled the system. Put the FEL and bucket through their full range of motion five or six time for about two minutes. Drained the hydro system, the fluid was definitely thinner, still cloudy and I did have some trash come out. The trash looked like rubber and/or paint pieces no bigger than a small ground of coffee, but not much of it. I repeated the process everything worked fine, turned off the tractor drained, fluid was clearer and was satisfied it was now clean. I refilled the hydro fluid reservoir with fresh fluid and started the tractor and nothing!! The FEL did not work, the implement lift on the rear of the tractor, nothing!! Power steering was sluggish!! Now of course it has started to rain so the repair/troubleshoot will have to be put off till tomorrow. I thought about disconnecting the FEL to take it out of the system and see if that helps, as stated earlier I am hydro stupid but I do know a little about troubleshooting. Please help!!
Thanks,
kbone1

tillerkiller · Feb 11, 2006

It sounds like you just lost the prime in the hydraulic pump (or pumps, some have more than one). Some people pressurize the hydraulic tank to help the oil 'find it's way' (NO MORE THAN A COUPLE OF PSI, or you will blow a seal.) Maybe instead just crack the fitting at the pump outlet to relieve the head pressure. Be watchful here, a lot of oil can come out in a short time. Once you pick up the oil and get all the air worked out of the system you should be fine.

Harrygoodwrench · Feb 11, 2006

First thing. Disconnect the tractor disconnects and plug them all together so the FEL is out of the circuit. Then start the tractor and see what you have. Cycle the steering, then the 3 point. Then if all is okay then shut down and retry the FEL.
NEVER run engine with quick disconnects unhooked. Pump damage will occur.

bruce1966us · Feb 11, 2006

Sure you have enough fluid in there?

Soundguy · Feb 12, 2006

I'm with the others.. I'd burp it at the pump to see if I had oil there.

That aside... I'm not a fan of running somthing very thin and with a low vapor point like straight kero thru a hyd pump. That low vapor point cause one big problem.. cavitation. While it usually doesn't happen in seconds.. I have certaintly seen minutes of cavitation kill some hyd pumps..etc.

I think a better flush would be a 50-50 mix of kero and the oil oil.. or by adding something like seafoam-transtune to the oil.. running, then draining... It's a hyds safe flushing agent, and a very good de-waterer.

Good luck.. hope it's just a bubble... That kero for sure washed the pump dry... might have been very easy to lose it's prime..

Might even dribble some oil in the pump outlet/ squirt some int he inlet to coax it to prime before you power it up. Old ford vickers engine mounted pumps were finicky like that. ( they went to a piston design in mid-to-late 50's to correct that.. )

Soundguy

Dave_Lilly · Feb 12, 2006

I would check to be sure the hydraulic system is turned on. My KAMA 354 has a lever next to my left foot that totally disengages the FEL and the 3PH if it is accidentally pushed down. The lever was cut off short by my dealer because of the problem of inadvertent stepping on it. If you have a separate hydro pump for the power steering, I would suggest draining the Kerosine/hydro fluid at the steering cylinder, then refill with hydraulic fluid. The manual for my KAMA and many posts on this forum say to use kerosene to flush the hydro and the gear lube systems, but I felt this was not to wise considering that the residual kerosine in the systems would only dilute the new fluids. I just drained the hydro and the gear lubes then replaced the Chinese crap with Autozone fluids. After I put a few more hours on the tractor I'll do a drain and change again.
Hope this helps.

bluechip · Feb 12, 2006

Dave,
not to hijack Kbone's Jinma thread, but if you cut that lever to about 2" long, you can still use it in the rare occasion that you would need to but much less likely to accidently disengage.
Kbone, the Jinma 300 series does not have this lever that Dave mentions. I would open a line near the pump and pour in oil, you should be fine.

I will admit that the answer that first popped into my head regarding the lost pump was to next time be sure to use locktite on the bolts! /forums/images/graemlins/wink.gif

kbone1 · Feb 14, 2006

I guess I over reacted. I changed the hydro filter, checked the lines, pulled the return
off the pump and reconnected it, and disconnected the FEL and presto!, my hydro system works. Reconnected the FEL, it works also, I do not know why all of a sudden the hydro system decided to work but it does. Everywhere I checked there was oil and when I took the return line off the pump a few small bubbles came up. I do not think that was enough to create a vapor lock like effect. I appreciate the guidance and suggestions.
Thank you,
kbone1