M4500 Hydraulic problem, brake disc replacement

jasowiii

Member

Equipment
Kubota L35
Jan 16, 2014
45
0
6
HomeTown USA
I just bought a 4500 with non-working hydraulics. 3 point lifts intermittent and real slow and the remotes (front forks) hardly move at all.

I found the remnants of a gasket (see image) in the filter. It does not appear to have a pick-up screen. When I look into the fluid filll port I see a reasonable amount of flow.

Any ideas on where to look for clogs from the gasket? Maybe a relief valve stuck open? It looks like someone scraped a big gasket of and let it fall in the gearbox! I put the blue smoothy can in the image for reference.

Jim
 

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jasowiii

Member

Equipment
Kubota L35
Jan 16, 2014
45
0
6
HomeTown USA
I am guessing this relief valve is in front of the 3 point in the circuit. I was assuming that since the 3 point acted like the remotes that my problem was more of a system issue. From what I read in other hydraulic problem threads, it looks like maybe this relief could be stuck open and dumping pressure such that nothing works.

I'll take it apart next week and post if I find the problem.
 

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007kubotaguy

Well-known member
Lifetime Member

Equipment
B7100DT L245DT JD 2355
Dec 23, 2012
646
258
63
Herald Calif.
Hello
I think if you look closely at the material you will find it is brake lining. I would drain the oil and remove the suction line from the side of the rear axle house right-hand side. This is the large line that leads to the cleanable filter on the right side of the engine. I think you'll find that line is plugged up. If you continue to run the tractor you will eventually have metal to metal on the brakes. Then you will have fine metal material throughout the entire transmission,rearend, and hydraulic system. This is a very common problem with these tractors. Good luck.
Lance
 
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jasowiii

Member

Equipment
Kubota L35
Jan 16, 2014
45
0
6
HomeTown USA
Hello
I think if you look closely at the material you found it is brake lining.
Wow! Who'da thunk it? The hydraulics don't work because the brakes are bad!

I think you are right. I looked at some fresh brake discs today and the fiber pad is much thinner than I would have thought. One of the chunks has a groove in it for the oil just like the brake discs.

Thanks for the advice 007.
 

Kubota Newbie

Active member

Equipment
M4500, New Idea Cut-Ditioner, JD 14T Baler, IH "Plow Chief" plows, Oliver Rake
Dec 28, 2010
533
81
28
Mount Vernon, Ohio
You're right, your 4500 doesn't have a suction screen. The "canister filter" on the right side of the tractor at about the rear of the engine +/- is the screen. It is a VERY fine mesh, there's a magnet up the center of it too. The relief valve is in the auxiliary control valve assembly on the right side of the seat it is adjusted via shims to 2,417 - 2,559 psi by changing the shims (WSM pg 256). What you see in the "fill" port is just oil movement from the tranny gears. Intermittent problems could be a broken spring, but not likely. Does it make noise when going up/down? The hydraulic troubleshooting flow chart in the WSM is 6 pages long. I could probably scan it for you.