Farmall 806 Hydraulics and 3 point not working

Hi all! I bought a 1964 Farmall 806 Diesel at an auction earlier this year. It starts and runs good, but the tires were shot. After I finally got new tires I tested the 3 point and hydraulics and they won't lift any weight. I then changed all the fluid and filter (it was pretty milky) and tested again, still nothing. Based on other posts I believe either the relief valve or pump could be bad. I don't have enough money to take a guess, so I was hoping someone here might have suggestions for ways to treat and eliminate different problems. Any help would be appreciated, thanks!
 
Since you changed filter and oil. does the steering work along with brakes and Pto. If none of these things work remove the cover on the bottom of the clutch and see if the rear shaft is turning with the engine running. If not then it is split time if it is have somebody pull a hydraulic lever. Sometimes they will turn with no load on them and stop with a load if they are bad. My 806 did that while I was spraying a few years ago. If steering works and PTO turns then it is either the oring is not in on the tine cup behind the filter,relief valve is bad or pump. You can try putting 5 gallon over full in also. I have never had that problem of a cracked tube inside. If all this checks out as good then you will need to put a flow rater onit to find out of it is just not flowing anything or not building pressure. You can remove the third link plate over the PTO and look at the linkage to the right side of the hole and see that it is connected and has not shifted out of alignment. That will cause a problem with 3 pt and not really affect remotes. there is a plug on the pump down by the left side on the Pentagon looking casting there it could be loosened a bit to see if you get pressure there. This is on the pump directly so be cautious about oil under pressure there. It has an o-ring for a seal on it. could be loosened then started watched then shut off if it flows under pressure. Brakes ,Steering ,and trans lube off a separate pump.
 
Steering and brakes work fine, and PTO turns (haven't tested PTO hooked to a load yet). All that worked well before changing the fluid as well. I did take the top link cover off and saw the hydraulic fluid coming down from the top, but it doesn't appear to spray when lifting the 3 point. I'm just trying to avoid buying the new pump if there's something cheaper I can try first.
 
When I changed the fluid, I did take the pump off. All the o rings looked good. I oiled them up and put them back on. I spun the pump by hand and felt some pressure on the one port, but not sure if it was enough.
 
Unless you pulled the pump separately. You would not have had the pump off while changing the filter or this is not an 806. The other pump is behind the MCV bolted to the back of it. I am guessing you are having a priming issue. Can you try a rag in the dipstick hole with an air hose as it idles. And don't pull the rag out with the hose leave it over the hole till the pressure is off after you get the prime.
 
Yes, I had the pump out separately. I figured since the fluid was out that would be a good time to pull the pump and check it out. I'll try the prime method you mentioned.
 
Well lets start off with you NEVER reuse o/rings . If the rear hitch pump was NOT working before then that is why it probably at a sale as the person that had it was not going to dump more money into it . So really with out being there we are all guessing . You say you have steering and brakes , ok so that takes the MCV pump out and so that the problem is in the rear hitch pump , So you pulled the pump did you get the pick up tube back in the pump ?:? you said you oiled up the old o/rings Bad deal you never reuse and O/Ring , So pull the filter and the pump and install new o/ rings then reinstall the pump then make sure the pick up tube goes back into the pump then reinstall the tin plate making sure the square o/ring is on it then the filter and a new cover gskt . Now once this is all done then now is when ya need a Flow rater to see if it has any flow . Is the 3 point up or down ?? If it is up and won't come down then the draft control linkage jumped off the arm on top from the arm coming up from the bottom , Ya need at least and I T manual to understand somewhat . Ya may have the unloading valve stuck open and dumping everything providing that the rear pump is really turning so make sure that the PTO really works . Now IF you were really really close to N/E Ohio it would be and easy fast service call and a quick plug in with my flow rater would tell all.
 
If I had the right O rings on hand, or if they looked bad, I would have just replaced them. I'll try to find the right o rings and replace them. The tractor was part of an estate auction, so I don't think the hydraulics is why it was for sale, but who knows. Yes, i got the pickup tube back in. The 3 point moves up and down fine, but won't go up if there's weight on it (i.e. if I sit or stand on it). I'll also test the PTO today, I have a PTO generator that should provide enough resistance to be a good test, I think.
 
W@ell the best way to save money and time on this problem is to find someone in your area that has a flow rater and knows I H hyd. that you can trust and have them test and check it out . we all can play key board expert and you can chase a ghost emptying your piggy bank and wasting time . When ever i had someone come to me with a Hyd . problem we did not mess around with well lets do this and oh well that did not work so lets replace this I tested before i picked up a wrench and stated spending money . Myself i am the only independent that has a flow rater anywhere around me , the others do as you do GUESS and spend money . one more thing to try make sure your draft control is not all the way down pull it up and inch and a half off the bottom .
 
Thanks, I will ask around and find someone that can test the flow rate. I noticed today that the draft control lever is stuck all the way up. I'll have to tear that apart and fix whatever is stuck, but do you think that could cause any of these issues with the 3 point and aux hydraulics?
 
Oh, and I forgot to mention. The 3 point arms don't lift until I rev it up a bit. Somewhere around PTO speed they start to move. Not sure if that's normal or if they should move even at idle.
 
Ok, I did a few of the tests:

- Tried the air hose in the dipstick hole with the rag as caterpillar guy suggested, no change
- Still asking around for someone with a flow rate tester
- Hooked up the PTO generator and I was able to get it up to the green section and plugged in a drill to verify it worked. Not a lot of load, but still some resistance
- I then ran it at that speed for a good 30+ minutes with a 6 foot disc hooked on the back. The oil got warm (never really hot), but no change in lifting ability

This weekend, I'll re-drain the fluid and take the pump off again and change out o-rings. I'll just have to find someone that has the right ones. If anyone happens to have a parts manual for the 806 and could let me know the part numbers I need, I would appreciate it. If not, I'll try calling Bates or someone else to see if they can look it up for me.
 
Most likely you will have to find a dealer for getting the flow rate test done. Most people will not have a flow rater anything to check the flow under pressure. One could be built if one was really forced to.
 
I finally got the new o rings and gasket installed. When I drained the fluid to remove the pump, I also checked the gears for any play or worn teeth. Everything looked and felt good. Re-installed the pump and filled the fluid, no change in behavior. The three point arms don't start moving until about half throttle, but if I put weight on them they stop. At full throttle they will lift about 150 pounds. Could that still be the pump or should I look at something else? If it was the pressure relief valve, would it have this behavior?
 
Just to wrap this up for anyone that ends up with the same problem, I decided to buy a new 2000 psi relief valve (around 200 at Bates), and the Hydraulics work perfectly now. It was the easiest part to replace so I went with that first.
 

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