3 point lift failure in cold weather

Millweld

Member
The 3-point lift on my Ford 641 (1958) will not raise in cold weather. Lately we've had temps in the teens to 30s - that's when it won't work. In the 40s it will raise but is jerky. The hyd fluid is not low. I changed it yesterday anyway thinking the old was dirty and perhaps it needed changing but that did not solve it. The shop manual shows no filter or screen so I don't think it is clogged with sediment. Any ideas?
 
I had similar problems with a 3-cyl 2000. Rebuilt and set up the valve, no change. Put new O-rings in the pump, no change. Finally did a rebuild on the pump, mainly check balls and seats. The old ones looked OK but after bleeding the air is works great. I don't know if yours would have the external piston pump.
 
Which oil is in the hydraulic system. In my 641 I have sae 90 mineral oil and when cold it takes a minute for the lift to work. Once warmed up everything is fine. My system is pretty worn and the 134 stuff is just too thin.
 
Thinner oil does help plus if you park it so the 3 point is up and sitting on something that helps also. In cold weather my 841S will not work the 3 point well till it has warmed up but if I block the back blade up when I park it the 3 point goes up while I am trying to start it. If I park it and let the 3 point go down it can take 15 minutes for it to lift the back blade so I just block it up. Been that way for well over a decade and have yet to figure out why so I just use it as is. Back blade by the way has 6-85lbs suit case weights on it so it is very heavy so that might have something to do with it also
 
I had Pennzoil HydraTrans as the hydraulic oil for many years. I replaced it yesterday with NAPA's brand. Both seemed to be the same viscosity - about a 10 to 20 wt oil, rather thin. After replacing the oil I let the tractor run for 10+ minutes with the lift handle up but the 3 pt lift never rose. The temp was in the 30s and today is colder. When the weather warms to the 40s I will try again and if the arms go up as I expect them to, I will prop them up as suggested.

I hesitate to take the pump apart until I know what to look for. I will hold off on it. It's interesting that others have observed the same thing. Thanks for the input.
 
If you have the 3 point control in the lift setting while your trying to start it does the 3 point go up or stay down?? If it goes up as your turning the engine over then it does as mine does and for some reason on my 841S it seems the slower speed of cranking it pulls the oil while the high RPM of the engine running it takes more time to lift. I am thinking due to the cold the oil is thicker so the pump has a harder time pulling it up to it self
 
I can't explain it either. Could have been just air in the system. Maybe I just got a better bleed after the rebuild, but it worked fine in warm weather and I used it with a 3-point hay rake and haybine on the remote. When cold it would not lift or lift slowly with chattering.
 
Well, I have done nothing more to my 3pt lift hydraulics. However, the temperature rose to near 70 today and the lift works perfectly! Sounds like a viscosity issue but I am using 10 -20 wt hyd oil as specified in the manual. I don't get it but I am OK with it for now.
 
Well if your temps got down to lower then say 32 degrees over night you may well have a bit of a water problem. Or of course as oil gets colder it gets thicker and that can cause a priming issue at times
 
I add a bottle of red HEET fuel conditioner to the hydro oil that I suspect is a bit waterlogged ,. I t helps keep the ice from plugging in the filters,,..
 
This AM it is 25 degrees so I started the tractor and the hydraulic lift worked perfectly. So water in the oil must not have been the problem. Perhaps it was just sediment or similar crud that finally dissipated when I changed the hyd oil.???
Thanks for all the replies.
 
It could still have been a water problem and in changing the fluid it got most of the water out.
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top