farmall 400 hyd pump: how to i split it open?

DerekD400 · Nov 19, 2011

tractor runs fine but the pump quit working. It was starting to make noise recently and it acted like it lost its prime several times. I have my pump on the bench now, and pulled off the worm gear and the driven helical spur gear. I took all the bolts out that hold the two housings together but for the life of me I cant get it to open up. Even with a 3 prong puller, i cant get it to separate. Any Ideas?

pete 23 · Nov 19, 2011

Nothing holding it together except many , many bolts. Sits on a couple of alignment dowels but should pull apart rather easy.

NEKS · Nov 20, 2011

May not be the pump. Probably getting air in the system from some where. There are lots of O rings and gaskets that can let air in. Need to put a clear hose in the return line and see if the oil is milky with air. Had a Farmall loving neighbor helping and I was about to give up looking, he kept telling me, we have to look farther. Ha we did find it.

DerekD400 · Nov 20, 2011

well, since the pump was starting to whine, for its last few weeks of operation... i really think something is wrong with it. Does anyone have a schematic of the pump? also, since its already on the bench, i want to see inside. but i'll keep the air leak option in mind when i put it back together.

Does anyone know how to get a rebuild kit?

Also, where is the screen located?

thanks,

Derek

CNKS · Nov 20, 2011

The "rebuild" kits can be had from CaseIH, but contain only seals and gaskets. Check the oil level in the engine, hyd oil could have leaked past the seal in the pump into the crankcase, making the pump dry. If that caused the whine, then the only solution is another pump, as they basically are not repairable.

biggerred · Nov 20, 2011

screen is bolted into the side of the oil reservoir. (4 bolts on the same side of the tractor as the pump, back under the light) Drain it first!!

DerekD400 · Nov 21, 2011

So, my filter was shot, most of the fine mesh was missing. so for, i'm sure, years, it was running everything through the pump. When i got the pump open (after removing the 2 5/17 12 point bolts that were not super obvious)it was clear that the aluminum housing is shot... aka, pump is shot. I bought a used one for $250.. i'm not happy about it, but i don't feel like buying a new one either.

While i'm under the hood, i notice that most the wiring is junk too, so i'll replace that all while i'm there.

thanks for the help.

farmall 400 hyd pump: how to i split it open?

DerekD400

New User

pete 23

Well-known Member

NEKS

Well-known Member

DerekD400

New User

CNKS

Well-known Member

biggerred

Member

DerekD400

New User

Similar threads