FEL Shudders & Shakes

[MNBobcat]

Hi Guys,

When I first start my tractor and want to use the loader I have to hold the hydraulic lift lever for a good minute or two before the FEL lifts. It will shake and shudder a bit and then after using it for a bit its fine.

I'm guessing this means air in the system? Is there a way to bleed it? I blew a hydro line last year so its entirely possible I got some air in the system. I tried lifting the FEL until it was fully extended and dropping it several times. But every time I first use it I get the same thing with it shaking. What's the fix?

 

[magicheater]

check your fluid level

 

[oldnslo]

Hi Guys,

When I first start my tractor and want to use the loader I have to hold the hydraulic lift lever for a good minute or two before the FEL lifts. It will shake and shudder a bit and then after using it for a bit its fine.

I'm guessing this means air in the system? Is there a way to bleed it? I blew a hydro line last year so its entirely possible I got some air in the system. I tried lifting the FEL until it was fully extended and dropping it several times. But every time I first use it I get the same thing with it shaking. What's the fix?

MNBob,
what type of tractor do you have and what type / weight of oil is in it?

Sounds like you are starving the pump at start-up and once warmed up a little it works fine.
Is there a growling noise coming from the pump area when the FEL is jerky? This would also indicate pump starvation or cavitation.

Does this unit have an inlet screen / filter? If yes has it been cleaned recently?

Roy

 

[MNBobcat]

MNBob,
what type of tractor do you have and what type / weight of oil is in it?

Sounds like you are starving the pump at start-up and once warmed up a little it works fine.
Is there a growling noise coming from the pump area when the FEL is jerky? This would also indicate pump starvation or cavitation.

Does this unit have an inlet screen / filter? If yes has it been cleaned recently?

Roy

Roy,

Thanks for the response. Its a John Deere 3020 diesel. I got the tractor last fall and one of the first things I did was change the transmission fluid and filter. On this tractor there is a cover over the transmission filter and the FEL hydraulics are fed from a hose connected to that cover. The hydro levers for the FEL are mounted on the right fender.

There are two more levers that are on the dash, which operate the hydraulic ports on the rear of the tractor. I use them for attachments.

The oil is whatever John Deere recommended for the transmission. I do get a whine from the hydraulic pump but I've been told that's normal for this tractor.

 

[mmurphy]

I think you may want to get a pressure guage to hook in to see what you have for pressure at start. It could also be an internal leak. Can you see in the sump area when running for lots of air bubbles? Maybe after running and getting things warmed up it doesnt leak as bad. I do also agree with Oldnslo.

 

[Soundguy]

also check any quick connects in the lines to make sure they are fully seated good.. might be sucking air..

soundguy

 

[bp fick]

When I installed my new FEL last month, it did this same thing until I finally got all the air out. It self bleeds, if you will. Well, I thought I had all the air out. It just kept stuttering. Felt it HAD to be a loose fitting somewhere. Sure enough, tracked it down. One fitting was loose from the factory. Just the slightest bit, just enough to seep fluid.

I had a loose fitting on the tractor too, when it was delivered so I suspected and half expected I'd have to check them all.

Just something to eliminate. Check every stinkin' connection and line fitting.
I also had foaming, a bit, on the HST dipstick, which was also a give away there was air coming from somewhere. Here's hoping the best for you.

 

[mmurphy]

If you can safely leave loader up in air when tractor is off see how long it takes to drop. Watch fittings as suggested to see if they are leaking. If it is leaking that bad I would think you would either see it or hear it, darnest little things can bite you. AS far as replacing hose it should have pushed air out by now. Do you have a vent cap for the hydraulics? Is it clean or plugged? If it stays up lets say 4 hours, then start up and see if you have same problem, if not then you know for sure it is a leak that is syphoning oil out of cylinders, oil lines or what have you.