JD620 High oil pressure?

bleazenb · Dec 7, 2018

Working on a JD 620 and oil pressure gauge pegs to the high side when the tractor is running at any rpm. Needle returns to the low position when tractor is not running, anyone have any thoughts? It does have the original oil pressure fuel shutoff and sediment bowl assembly. I just rebuilt the fuel shut off system. But the high oil pressure issue was there before I rebuilt the fuel shutoff. Thanks for any assistance.

Mike M · Dec 7, 2018

Put a master gauge in and see what it is really at for psi. There is an adjustment spot near the belt pulley down and to the front you remove a pipe plug and adjustment screw is right in there.

bleazenb · Dec 7, 2018

Ok I will try that, where is the best place to tap in the master pressure gauge?

Mike M · Dec 7, 2018

Might be easiest to tap in where it hooks up to the fuel bowl ? IIRC 15 psi is all they need. I set mine a little higher so they hold 15 psi hot maybe at idle ? This would put a good working L-M-H gauge at the lower edge of -M- with oil warm at idle.

BushogPapa · Dec 7, 2018

Most likely at the place where the oil line exits the engine and leads to the oil gage....

RLA · Dec 7, 2018

Was the fuel shut off leaking gas into the crank case???

John Deere put a "O" ring in the main case at both main bearing quills.
Gas makes those O rings swell shut, cutting off or limiting the oil supply
to the Right Main & Right Rod & Lh quill Left Main & Left Rod. If your Oil
pressure remain really high, I would be looking at those O Ring Seals. Better
than burning the bearings out of it...

JD620 High oil pressure?

bleazenb

New User

Mike M

Well-known Member

bleazenb

New User

Mike M

Well-known Member

BushogPapa

Well-known Member

RLA

Well-known Member

Similar threads