Mf 399 hydraulic problem

[will_mck]

I've recently broke the lift cover on our 399, it's been replaced by a mechanic but I see the lever which boosts the oil flow to spool valves isn't working since and the oil flows at the standard speed. I've adjusted both linkages on the this lever individually but it makes not difference. Anybody any suggestions of what the problem is?

 

[aidan]

how did you manage to break the lift cover

 

[will_mck]

Went over a bump in the field whilst spraying. They've very light backends and it's a common fault

 

[Wellytrack]

If you have had a mechanic involved should you not call him?

 

[livestock 1]

Linkage not connected up inside?

 

[will_mck]

The mechanic said he might get a look at it next week. Be good if I could fix it now. I've a feeling the lift cover will have to come off again as there's something wrong inside. As far as I understand the lower linkage connected to the lever diverts the oil flow from the back end pump so there must be something wrong there

 

[MF CI]

I've recently broke the lift cover on our 399, it's been replaced by a mechanic but I see the lever which boosts the oil flow to spool valves isn't working since and the oil flows at the standard speed. I've adjusted both linkages on the this lever individually but it makes not difference. Anybody any suggestions of what the problem is?

Not sure what linkages you have been adjusting but always best to leave them alone and as the factory settings.
I think the lever for combined flow operates the selector valve to divert the oil to the spools and at the same time via a rod from the selector valve to the round cover where the dipstick goes puts the linkage pump into constant pumping.

 

[will_mck]

Not sure what linkages you have been adjusting but always best to leave them alone and as the factory settings.
I think the lever for combined flow operates the selector valve to divert the oil to the spools and at the same time via a rod from the selector valve to the round cover where the dipstick goes puts the linkage pump into constant pumping.

The mechanic advised to adjust them which i did individually to see if it made a difference. I counted the number of turns when I adjusted them but left them back to the factory settings after it made no difference. I maybe damaged something when the lift cover cracked. The lift arms and spools work normally apart from that booster lever not working

 

[will_mck]

I've just pulled the lift arm position lever up the whole way which puts the tractor into constant pumping and then pulled the combined oil flow lever up and I have dual oil flow now so everything must be working mechanically inside. I think it's the lower rod linkage not activating the constant pumping beside the dipstick, I have adjusted it as I said before but it made no difference