TO-35 hydraulics

1957 TO-35 ser #170154,Hydraulics drop rapidly when engine turns off,slow to rise.I plan on keeping this tractor,and would be ok replacing the pump,or rebuilding the pump,either one. I am a little confused by what I have been reading,new higher pressure pump style vs old pump style.Is there rebuild parts available for the old pump style(assuming that is still what is in my tractor) I have heard new replacement pumps can either not fit because of quality problems in online products,or only be for new higher pressure tractors. I see this site has new replacement pumps for sale,can some one offer any opinions on these pumps? Thank you for your advice.

take the right side cover plate off and with engine running look up inside and see if any oil is coming down. if not you may be be able to get away with just replacing the stand pipe O rings.

this site sells a DVD on how to do these things. There are utube videos out there too.

there will be other people along who are better versed to give advice than me.

There was a low pressure model, and a high pressure model.

By your serial number, and the info on this site, yours is the low pressure model. But there are discrepancies in the serial numbers. The sure way to tell, once you get in, the lift piston on the low pressure model is 2 1/2", the high pressure is 3".

There is also a difference in the relief valve. As long as it has the correct relief valve, the pump doesn't matter as long as it will fit.

The reason the correct relief valve must be used, the early low pressure system had a different top cover. Using the high pressure relief valve will break the top cover under heavy lifting!

I have more info on this in the shop manual, but it's at work. I can look Monday.

But before going further, do some diagnostics.

Open the right inspection cover. You won't loose much oil, you can drive the right wheel up on a block if you want to tilt the oil to the other side. Have a flash light ready, start the engine and lift an implement, or chain the lift down to put a load on the hydraulics. Tell it to lift, look inside (but never reach in with it running!!!).

Look up at the bottom of the lift cylinder. Some dripping is normal, but should not be streaming oil. If streaming, the cylinder seals are bad, possibly the cylinder is bad too.

Look at the top of the stand pipe. Should be no oil leaking. If oil is blowing from the top of the pipe, the oring is bad. easy fix from up top.

Look for oil roiling up from the bottom of the stand pipe, same thing, bad oring, easy fix.

If the arms are chained down, there will be oil bypassing the relief valve. This is normal. Backing off the lift lever should stop the relief valve from blowing, but they are known for leaking, so if you go in deeper be sure to replace the relief valve with the PROPER pressure.

As for the pump, symptoms of a bad or weak pump are slow, jerky operation. If the lift bounces on the way up, or jerks while holding position, the pump has valve problems or a broken piston. There are aftermarket parts available, but it's a gamble if they will fit properly. I rebuilt one, but had I not had access to a machine shop with a surface grinder and lathe, it would not have worked. Looking back, I would have bought a rebuilt pump over going through that again!

Getting to the pump, or the cylinder, requires lifting the top cover. The lever valve control system you see through the right cover, that extends all the way down from the top. It must be disconnected from the pump before lifting the cover. The lever assembly is fragile and complex, the cover needs to be lifted in a controlled manner so not to bend or damage the linkage. It is heavy!

While you're in there, there is a rubber boot on the draft control spring. The boot needs to be replaced, it keeps water out of the gear case. It is a real ##@$!! to replace. I had to cut the rod with a Sawsall reaching through the coils of the draft spring. Adjusting the spring preload is critical and covered in the shop manual.

I urge you to have a manual before attempting any of this. They are available on this site, Ebay, etc. Not expensive, and will more than pay for itself in mistakes not made!

Hope this helps, let us know how it goes. Don't be afraid to ask.

Here is info on the procedure I used to verify the Hydraulic OIL PRESSURE on my MF FE 35....
Lift arms down........and chained..
Operator Lift control lever forward / down...

Engine operating.....
Operator pulls up on Lift control lever....
Visually verify and record HYD. PUMP PSI....


Bob...

"Previous Owner Syndrome"

The owner of this T0-35..I suspect without purchasing ,reading and paying attention to said Manual....cost them big ..$$$$$...

Sh_t happens fast when hydraulic PSI is activated with out understanding the consequences....


Bob...Owner operator MF FE 35...

Thank you for your replies. Yes I have the service manual. I agree it is very helpful! I have time,am not in a hurry. I will proceed one step at a time. Looking forward to removing the right side cover and getting a better understanding.

wkndwrnch: I noticed you showed your serial number as 170154. That serial number is actually a 1956 not a 1957 as you think.