help please! John Deere 4020

Matt Waddell · Aug 14, 2009

i was out bushhoggin today with the ole 4020, and the the thing that the diesel goes to before the filter (im only 17 and i just got the tractor a few weeks ago) started spraying fuel everywhere, i dont know if its the fuel pump because as far as i can tell, if it is, it only pushes the diesel fuel through the filter to another pump which sends it to the injectors. but it comes from the tank (i guess) through that, throught the filter, and to the pump, and then to the injectors. the tractor ran fine on the way home but i left most of my diesel fuel in the field and on the road. and also when i use the loader with the bushhog up a little (still rollin on the ground) the loader dont hardly want to go up, and the hydraulic oil is topped off and the three point works just fine. i know im bein sketchy on my details, but its as good as i can explain it, so any help and tricks are appreciated. thanks

Bob · Aug 14, 2009

Sounds like your fuel lift pump (or a fitting in that area) failed.

Is the bushhog a three-point?

If so, the 3-point lift cylinder or valve may have failed, causing an internal high pressure leak that's using the whole output of the hydraulic pump to try to lift the 'hog, leaving no flow for the loader.

There's also a "thermal relief valve" for that cylinder that causes a massive internal leak when it fails.

Matt Waddell · Aug 14, 2009

i think it is the lift pump, because it seems to turn off the crank, or something down there. and how do i go about trying to figure out if its the thermal relief valve or an internal leak?

Dave Sherburne NY · Aug 14, 2009

There's a pump in the transmission that supplies oil to the front pump and I believe it also supplies the three point, brakes and steering. On a tractor I had, The oil line inside the trans came loose, not completely, but enough so oil wasn't getting to the front pump.
I THINK, If your lucky, JdeMaris will ad his experties to this thread. Ask this on the John Deere Tractors section down below.

Tx Jim · Aug 15, 2009

DAVE SHERBURNE NY[/quote]There's a pump in the transmission that supplies oil to the front pump and I believe it also supplies the three point

Trans pump doesn't raise 3pt,main hyd pump does that at 2250 psi if in spec.

Tx Jim · Aug 15, 2009

Matt Waddell[/quote] how do i go about trying to figure out if its the thermal relief valve or an internal leak?

You can feel each hyd function for more heat than others. Internal hyd leaks can be very hard to isolate. Have you checked stand-by pressure?

help please! John Deere 4020

Matt Waddell

Member

Bob

Well-known Member

Matt Waddell

Member

Dave Sherburne NY

Well-known Member

Tx Jim

Well-known Member

Tx Jim

Well-known Member

Similar threads