m4050 hydraulics quit after clutch change

[Forwheeler]

Hello all and thanks for looking at my post. I am new here, but I like what I see so far. I was looking for some advice on what to do with my tractor. I tried the local kubota dealer but did not get much help.

Ok so here's the deal. I had to split my tractor recently to work on the clutch. Fixed the clutch and put it back together. Runs fine, but the hydraulics quit completely. They worked without any difficulty prior to the split. I did have to separate the large hose that runs from the back of the tractor to the front. It did lose approximately 2 gallons of hydraulic fluid in the process. I filled it back up, no worky. Not any movement whatsoever. It does have a loader. It also has a separate power steering pump that is working just fine. Loader and three point do not move at all. Any thoughts?

 

[North Idaho Wolfman]

Some models need a little help getting the pump primed after air has been induced, it's usually caused by a small bleeder hole inside the pump becoming clogged.

Crack the high pressure line, crank or start the engine, being prepared to shut it down quickly when fluid flows.

 

[Bulldog]

How long did you run it trying to get them working?

After I changed oil on my first M9000 I had to run it 15 or 20 minutes before the hydraulics started working.

 

[Forwheeler]

Thanks for the quick reply. I ran for 3 minutes the first time and 8-10 minutes the second time. I will try to run for longer.

As for priming, pardon my ignorance, but I am not sure which one of the lines is the high pressure one. I have a large line (bigger than my thumb) and a smaller line (ring finger sized) that I separated to split the tractor. Which one should I crack?

 

[100 td]

Make sure you have a proper seal and no possible leaks on the big pipe join. If you can get access to the inlet of the pump (big hose) you can crack it there and allow oil to bleed thru to this point and air to escape, or the same at the return filter (depending on gravity, height of oil, flow thru filter etc this may not be possible). You could have an airlock at the inlet to the pump back to the return oil filter.

 

[007kubotaguy]

Hello
Do not run the tractor until you fix the problem. You have lose the prim and the pump is running dry. Just remove the large pipe from the top of the pump and pour a little hydraulic oil in to the pump. Also check the filter screen and clean . How many hours do you have on this tractor?
Good Luck Lance

 

[Forwheeler]

I have 1300 hours on the tractor. It is an early 80's model. I will try that tomorrow on my day off. How do I find the screen/filter for this tractor? I looked online in several places, could not find anything helpful.

 

[Tx Jim]

Welcome to GTT neighbor.
I looked at parts schematic and can't locate a suction screen for your tractor. Have you changed hyd filter? After changing filter I'd suggest with engine running to blow short bursts of compressed air into hyd dipstick hole to help force oil into hyd pump to help prime the pump.
Jim

 

[007kubotaguy]

Hello
The suction screen is just to the right of the large hydraulic hose you talked about removing. There are three bolt on the bottom of the housing you need to remove. You should find a spring and a metal screen with a removable manganite in side of it. Clean them and put back together. You should find a rubber gasket on top of the filter and a spring between the cap and filter. After this try pouring oil in to the top of the pump. If you do try to blow air be vary carefull as you can blow the seals out of the front of the transmission. Let us know what you find in the filter.
Good Luck Lance

 

[Tx Jim]

Hello
The suction screen is just to the right of the large hydraulic hose you talked about removing. There are three bolt on the bottom of the housing you need to remove. You should find a spring and a metal screen with a removable manganite in side of it. Let us know what you find in the filter.
Good Luck Lance

I'm curious.Is it a screen that requires cleaning or a filter that requires changing in the canister you refer to? Kubota states it's a filter. Blowing "short bursts of compressed air" into hyd dipstick hole more than likely will not blow any seals.

 

[North Idaho Wolfman]

The red (smaller line) is the high pressure
The blue larger line with the filter canister (yellow) inline is the suction line.
This model does not have a suction line screen that would be located either in the rear case or in the start of the suction line.
if you haven't pulled the filter canister apart I would do that and replace the filters.

Magnetic filter (#5)
36200-82644 $22.00
Composite filter (#4)
36200-82630 $57.95
Filter gasket (#9)
36200-82650 $12.10
O-ring (#12)
04811-50950 $2.10

 

[Forwheeler]

Hello all. I wanted to say thank you for all the help. You guys are great. The short story is that I got it working.

That diagram is great, I did open the bottom of it and LOTS of hydraulic fluid started coming out (engine off). How much fluid should I be prepared to lose out of that? Anyway, I closed it back without completely opening it until I knew how much fluid I was going to lose.

What I did to get it working was to crack the high pressure hose (engine on) that goes to the hydraulic lever to control the front bucket. It bubbled for about 5 seconds and then I had to duck to miss the spray coming out. I shut it down, tightened the hose, restarted it and it works just fine now.

I would like to change the filter, I just want to know how much fluid I am going to lose.

Thanks again!

 

[D2Cat]

Forwheeler, here's an option I did on my L305. It's a smaller tractor then yours, but appears to have the same filter setup.

NIW give me the guidance to get it completed. About $25 in parts, a little time and you have an easy to service filter.

First picture is the old, then the new.

That mounting bracket was something out of my "bone pile" off of a window AC mount. Sad to say, it's still on there!!