300 (1020) backhoe hydraulic problem Please help.

[300 Backhoe]

Hello
Just purchased a 300 backhoe. 3cyl gas. When starting the tractor,it will crank over fine then it acts like the hydraulic pressure builds, then the engine cranks very slow.The only way I can (sometimes) get it to start is to move the steering wheel left to right while cranking. If it does get started the steering column gets hot in a short amount of time. Could anyone recommend what I need to look for. Thank you for your help.

 

[jenkinsph]

I would suspect the steering valve first. The steering and brakes have priority over everything else on the tractor I should add. Just a hunch but I suspect the steering valve needs to be rebuilt.

 

[Tx Jim]

The steering and brakes have priority over everything else on the tractor I should add. .

jenkinsph
Your statement is true on Waterloo tractors of the same era but the priority valve on JD utility tractors has zero to do with providing trans pump oil to the brake valve reservoir. Yes priority valve on utility does give power steering priority oil.

 

[jenkinsph]

jenkinsph
Your statement is true on Waterloo tractors of the same era but the priority valve on JD utility tractors has zero to do with providing trans pump oil to the brake valve reservoir. Yes priority valve on utility does give power steering priority oil.

You are right, I should have thought of that since my 820 didn't have power assist but the 4020 did if I remember correctly. Seems that below 1900 psi the priority valve closes off the other hydraulic functions and runs flow to the steering as a fail safe. I am going back to the mid 1970's so my memory may be lacking. At any rate what do you think about the steering valve being a prospect?

 

[Tx Jim]

I totally agree with you on the steering valve as needing seals replaced.

 

[J_J]

Do you have all the the hyd valve levers in neutral when starting?

You could put a hyd gage in the IN port of the BH valve and see if there is any pressure at start up.

Recheck any QD's you might have.

Is the filter good?