806 Hydraulics

[Backhoe Bob]

I have a 1964 806 gas. Yesterday the hydraulics decided they wanted to quit. Pulling a 15ft. batwing, the wings quit lifting, 3pt. won't lift, power steering works, brakes work. What could cause this? Clogged filter? Will change it next trip to the farm. What else could it be? Where is the pump located? Any help aappreciated. Thanks Bob

 

[Cory Schmidt]

Check the filter first, the pump (if like 706) is on the other side of tractor from the filter. There are two pumps, one(more forward, below the gas tank, under T/A valve(when equipped)) for breaks and steering and T/A. The other is behind the steps, directly across from filter for hydraulics. Had the key on this second pump shear on the 706 already, I think this is your problem. If you pull the pump have a few clean enough for oil 5 gallon buckets on hand then slowly pull the pump and drain the oil. When done I strain the oil through a old sheet and funnel it back in if its still clean looking/ have none on hand.

 

[Backhoe Bob]

Cory, Thanks much. Farm is 70 miles away, would like to take a key with me when I go. Do you know what kind it is? Straight or half moon? Thanks

 

[Cory Schmidt]

in the 706, I would think it should be same for a 806, its straight 1/4 in(if I recall right) square. don't recall how long or any other details, sorry.

 

[caterpillar guy]

I would start with the oil level then the filter. The key is square about a half inch long. There are 3 plugs to drain the oil for the pump removal. One up over the drawbar then 2 on each side under the final drives. The center one takes a 1/2 inch drive the other 2 take a 3/8 drive. All square unless somebody has changed them over the last 40 years. I have just simply had the nut come off letting the gear loose.

 

[Owen Aaland]

The most likely cause and easiest to repair is a relief valve stuck open. It is pilot operated to if a tiny bit of debris gets caught in the pilot valve the main part of the valve will slide right open as soon as there is any oil flow.

The valve is located just below the seat on the right side. There are two plugs there with 1 1/8" heads. The one with the numbers on it will be the relief valve. early valves will have the pressure rating stamped into them, later ones the IH part number.

The easiest way to test the valve and system if to replace it with a known good valve.

 

[Jim Naden]

(quoted from post at 16:36:08 11/01/15) I would start with the oil level then the filter. The key is square about a half inch long. There are 3 plugs to drain the oil for the pump removal. One up over the drawbar then 2 on each side under the final drives. The center one takes a 1/2 inch drive the other 2 take a 3/8 drive. All square unless somebody has changed them over the last 40 years. I have just simply had the nut come off letting the gear loose.

Don't drain the final drive sections for pump removal, on an 06 series the finals were separate from the main reservoir, the level is checked and maintained at the check plugs on the final drive housings.