International 3850 Wheel Loader (tractor) bucket hydraulic issue....insight needed!

[Musicbar]

I have recently purchased an International 3850 wheel loader ('77 vintage). I'm repairing hydraulic leaks...no problem. However, my bucket...when fully curled...will slowly fall. The lift arms are rock solid...no lowering. I have no obvious leaks around the bucket rams...and now no obvious hydraulics leaks in general. So....what do you think it could be? Bypass at the valve handle.....? I guess my question is two-fold...1. How can I troubleshoot this further? 2. If it is something like bypass at the valve handle, is that something that is relatively easy to fix?

Hydraulics are not my specialty by any stretch...but I'm a farmer and work on all of my equipment and am handy.

I appreciate any suggestions. Thanks!

Lynn
http://lifespringfarms.com

 

[J_J]

It could be caused by cyl seals or worn valve spools.

 

[Musicbar]

J.J....thanks so much for your reply. So would you recommend that I take the cylinders apart and repack with new seals, etc...? Also...forgive my ignorance, where are the valve spools located?

Thanks!

Lynn

 

[J_J]

You need to troubleshoot your cyl and see if they are the problem.

If your cyl are good, then the spools in the valve are leaking due to wear.

The spools are in the valve with a lever that you raise the lift arms and control the bucket.

You can not just replace the spools, as they are a precision fit.

There is a leakage rate that dealers will have to replace a hyd valve. After that, it is how much leakage you can tolerate. Some valves have o-rings that can be replaced.

A new loader valve in in the $250 to $400 range.

 

[Xfaxman]

Is there any oil leaking from the bucket cylinders, valve or hoses?

 

[SIMassey]

I have no obvious leaks around the bucket rams...and now no obvious hydraulics leaks in general.

Lynn
http://lifespringfarms.com

J J, isn't there a way test for leaking cylinder piston seals you described in another thread?

 

[J_J]

Remove the hose from a matching cyl and cap the lines.

With the cyl retracted, remove the base end hose from a single cyl and retract the cyl some more.

If you have flow, the seals are bypassing.

 

[SIMassey]

Remove the hose from a matching cyl and cap the lines.

With the cyl retracted, remove the base end hose from a single cyl and retract the cyl some more.

If you have flow, the seals are bypassing.[/QUOTE)

Thtat should help the OP and anyone else in the future if they suspect bypassing. This will rule out the cylinders and leave the valve as suspect if the cylinders don't bypass.

 

[Musicbar]

Thanks for the advice. I am heading to the shop and will do as you suggested and will let you no what I found. Again, thanks a ton everyone!