Early TO35 Hydraulic Pump and Cracked Lift Cover

[PhillipsTO35]

Hello Folks.

I have a 1955 TO35 with a cracked lift cover. The previous owner left the bolts loose which probably contributed to the crack. I also need to look at getting a new hydraulic pump since from what I have read you cant rebuild these early pumps. My tractor has a 2 1/2 cylinder so can I use a new pump as long as the pressure relief valve is for the 2000 psi system? Also, what are my options for a new top cover? Can I used one from a later 35,50, or 65? I know the new ones are thicker and work with a 3 cylinder. I guess my question is what are the best routes for getting this thing back into action.

Thanks in advance for all the help.

 

[Jim in rush co]

Here is a little info. I rebuilt my pump TO35 1955 with the help of an old MF dealers parts and a couple tools to grind the
valve seats. My lift cover was still good, I included pictures from parts book and serial # breakdown as to use. Hope this helps
also check transmission casting as I have seen those cracked when the lift cover goes.

 

[Steve@Advance]

You can use a later model cover, 3" cylinder, and pump.

Last I heard there are no 2000 lb relief valves to be had. You can order them, but when it comes it will be the 2750 valve.

I rebuilt my pump, but it was a real challenge. The aftermarket parts were not correct. If I didn't have access to a machine shop it would not have worked.

Finding a rebuilt pump is much easier, just be sure it will fit. Been lots of changes, some fit, some won't.

 

[PhillipsTO35]

Thanks for the help Gentlemen. I appreciate your time and
information. I was looking for those pressure relief valves last
night. Thanks for helping to end my search. I was having no
luck👍

Any further information is always great from

I wish there was a tractor salvage yard near me. Anyone
know of any in the central or western part of N.C.? I hate to
spend a fortune on an old tractor that I will be using and not
restoring. It has some other issues I’ll have to address in the
next few years too. I found a top cover near me but I’ll have to
order a cylinder And I found the top covers online but the
shipping kills you.

I think we’re going to tear the pump down today and have a
look.

Many thanks.

 

[PhillipsTO35]

My dad is a machinist and has made a plate that spans bolt
holes to pull the top together tight. It seems to have been
broken for a while. It’s not split all the way across.

What do you guys think about putting in a new pump and
putting the pressure relief valve from the original pump on the
new one and leaving the original cylinder?

Thanks for the help.

 

[Steve@Advance]

"If" the original relief valve is still good, yes you can.

But the old valves are known for having water damage from sitting in a water contaminated case. The spring rusts away, the seat pits, they leak.

I suspect if you use the small cylinder, and every thing about the linkage is properly adjusted so it doesn't go all the way up and keep on pumping, it will probably be OK.

I've thought about cutting open a 2750 and making an adjustable valve out of it. Never actually got around to it, but should be doable.

 

[resden]

I have a hydraulic pump here from a TO 30. Text me if you want it at 920-286-1510. You will need to check if it will fit your unit.

 

[RedGreenGuy]

Relief valve on my TO35 went bad and cracked lid and case. When hi-pressure oil shot between my legs I was lucky it missed my body. Had relief valve tested. It would not crack open at 8000 lbs. Don't think you can find a new 2000 lb relief valve. I bought one advertised as such and had it tested 2800 lbs. After talking with a knowledgeable YT member I have it installed. Still working on completing tractor rebuild so not used it yet.

 

[John Deere D]

Here's an example from "YT" of a destroyed cover..

Owner of Tractor Started Tractor, not knowing any history or back ground of Tractor.....

Lift was not set at proper stop position...

After performing a HYD pump replacement on my MF 35 X, with PRESSURE GAUGE installed in remote HYD line,engine was cranked with fuel shut off. With lift lever up, attention was to psi gauge as lift arms approached top of travel. Gauge never indicated any psi as lift arms stopped before they over shot the max lift height.

Bob...Owner MF 35 X

 

[Dtractors]

I also have a 1954-55 TO35 with a cracked lift cover. Haven't been able to locate a good used "thicker" lift cover yet. Found several aftermarket top covers available on ebay listed under a bunch of different Part numbers: 1870955M2, 190861M1, 190861M2, 884612M92, 884615M1, etc, etc. Does anyone have experience the aftermarket lift covers and happens to know which one will fit an older TO35? Thanks

 

[scoobieguy]

As far as I know the top covers from a 50, 135 would fit your TO35, I did a swap to the thicker and larger piston a few years back see this post.

https://forums.yesterdaystractors.com/viewtopic.php?p=9089944&highlight=swap+lift+cover#9089944

Along with the lift cover you will need to longer bolts and taller standpipe.
Finding a complete tractor rear end or tractor with a blown engine is your best bet