Ford 5000 Hydraulic Problem Solved...Maybe

[Dave3]

Last year I was mowing with my 1967 Ford 5000. The PTO started slowing and then the 3-point lift stopped working. I thought it might be the hydraulic pump. I pulled the pump and the filter that is attached to it was completely clogged with sludge. I cleaned the filter and reinstalled the pump. Worked great the rest of the cutting season.
I was mowing two weeks ago for the third time this year and the same problem started. I removed the pump, and the filter looked clean. I decided it was time for a new pump. Got a new pump and installed it with little difficulty. I started the tractor and the 3-point, with the mower attached, lifted right up. Thought I was a tractor genius! In less than two minutes the 3-point slowly lowered, and the PTO stopped spinning. I'm sure you guys know the disappointment and frustration feeling after you think you have solved the problem only to find you wasted your time and money on the wrong solution b/c you diagnosed the problem wrong.

I dreaded the idea of taking off the lift cover. I decided the sludge might be causing the valves (unloader/control) to stick. I added two bottles of Seafoam Trans Tune to the hydraulic reservoir. Started the tractor and raised the lift. After a minute it came back down slowly. Shut off the tractor (only way to get the lift and PTO working again) and raised the lift again. This time it stayed up for two plus minutes and then lowered again. Did it a third and fourth time. The fourth time the lift stayed up and PTO kept spinning! I'm going to cut this weekend, and it will be the real test.

My question is what was or might still be the problem? Would it be the unloader valve was getting stuck?

 

[Destroked 450]

Pto works off the second small pump built into the main pump, the lift top will not effect the pto
For both to quit at the same time is either no oil getting to the pump or the pump has stopped turning, usually when the pto drive hub splines strip out from wear

 

[Dave3]

Destroked 450, Thanks for the note. I wanted to test it again this morning. The problem still exists. I replaced the intake filter attached to the pump, but did not change the return filter. I read that could cause both the PTO and 3-point hitch to stop working. I drained the fluid and got the old return filter off and waiting for new one to arrive this week. I hope this solves the problem. If it was worn splines I would assume I would have seen no improvement after using the Seafoam Trans Tune. I think the splines all look good. Can you tell from the picture? I also found no metal shavings in the bottom of the reservoir.

 

[Destroked 450]

The splines I’m talking about are in the drive hub bolted to the flywheel
Thou different my 4000 works similar, the drive splines stripped a couple years ago, no load everything worked fine but as soon as the lift or pto was under load everything stopped

The return filter has a bypass valve should it plug and will not effect the lift or pto’s operation

 

[Bern]

Destroked 450, Thanks for the note. I wanted to test it again this morning. The problem still exists. I replaced the intake filter attached to the pump, but did not change the return filter. I read that could cause both the PTO and 3-point hitch to stop working. I drained the fluid and got the old return filter off and waiting for new one to arrive this week. I hope this solves the problem. If it was worn splines I would assume I would have seen no improvement after using the Seafoam Trans Tune. I think the splines all look good. Can you tell from the picture? I also found no metal shavings in the bottom of the reservoir. View attachment 122241

To tell if the splines are worn, take a prybar and try to turn the big gear seen in the opening. If it spins freely, your splines are stripped. If it turns hard and the engine rotates at the same time, they are fine.

 

[Sean in PA]

I doubt that a clogged return filter could cause your problem. The return filter is supposed to have a bypass valve so that if the filter gets too clogged and the pressure gets too high, the bypass filter opens up and it allows the fluid to dump back into the sump unfiltered, so it doesn't block the flow.

 

[Dave3]

Appreciate the tips on the bypass valve. I looked closer at it today and it is missing the screw that is in bottom of it. Also, the holes on the sides appear much larger than on a new bypass valve. I will be ordering and installing a new one. From the pictures below can you tell if this was the correct bypass valve and with the screw missing was it stuck in the open or closed position? I assume not having the screw in the bottom would cause problems.

 

[Destroked 450]

That still has nothing to do with your issue

 

[Dave3]

Is it very difficult to change the drive splines? split the tractor?

 

[Bern]

Is it very difficult to change the drive splines? split the tractor?

What was the result of my prybar test? If the splines are stripped, you need to split the tractor twice, on both sides of the transmission.

 

[Dave3]

Bern,
I did your prybar test today and the big gear would not turn. I was putting good force on the 18" or so prybar that it was flexing. I will be installing the hydraulic return filter, and the new bypass valve this weekend. I will let you know the results.

 

[Bern]

Bern,
I did your prybar test today and the big gear would not turn. I was putting good force on the 18" or so prybar that it was flexing. I will be installing the hydraulic return filter, and the new bypass valve this weekend. I will let you know the results.

That's good news, it means your PTO driveline splines are holding, for now. Notice I didn't say they were "good". You could have 90% of the splines worn out, and it would still hold until one day they don't. Fortunately, this is not a big problem on a 5000.

 

[Fordfarmer]

Appreciate the tips on the bypass valve. I looked closer at it today and it is missing the screw that is in bottom of it. Also, the holes on the sides appear much larger than on a new bypass valve. I will be ordering and installing a new one. From the pictures below can you tell if this was the correct bypass valve and with the screw missing was it stuck in the open or closed position? I assume not having the screw in the bottom would cause problems.
View attachment 122437
View attachment 122438The return filter is circled in yellow in my picture. The bypass on it is simply a spring (just above the filter) that allows it to move up, and the oil can then flow out the bottom, bypassing the filter. What you're holding looks like a relief valve.

 

[Fordfarmer]

Don't know what happened to the text with my picture...
You're holding what looks like a relief valve. The bypass on the return line filter (circled in yellow in my picture) is simply a spring that allows the filter to move up, so oil can flow out the bottom, bypassing the filter.

 

[Hacke]

Appreciate the tips on the bypass valve. I looked closer at it today and it is missing the screw that is in bottom of it. Also, the holes on the sides appear much larger than on a new bypass valve. I will be ordering and installing a new one. From the pictures below can you tell if this was the correct bypass valve and with the screw missing was it stuck in the open or closed position? I assume not having the screw in the bottom would cause problems.
View attachment 122437
View attachment 122438

No screw at the bottom, the compressed spring (#52) may look like threads.

 

[Dave3]

I replaced the following and was able to cut for 3.5 hours with no problems.

-Hydraulic pump
-Return filter
-Back pressure valve
-Intake filter

I need to cut one more time this year and then I'm putting it in the garage for a new clutch, drive splines, clutch pack and anything else you guys think I should replace while I have it split in two places. The clutch is totally shot. I have to drop to less than 8000 RPMs to push it in gear with a little grinding noise.

 

[Dave3]

Was able to mow for 3 hours and then the lift went all the way up and would not come down. I parked the tractor under the pole barn, and I heard a popping sounds about 30 minutes later. The lift was slowly going down. I think it is time to remove the top cover and see what needs to be replaced.

 

[Dave3]

Anyone have a good link to the rebuild process for the top cover? Cylinder and seal replacement. Looking at kits online it appears there are a lot of o-rings to replace!

 

[SkipperII]

I suggest that you break down, and buy a repair manual. I might even suggest an owners manual, parts, and repair manuals.

 

[Destroked 450]

Did you completely drain the rear axle housing to get any sludge or water out
How much hydraulic fluid did you add to refill the axle, it should have been filled until fluid started coming out of the check plug hole
Originally you had a non oil flow is effecting both the lift and pto (pto drive not turning, plugged suction screen, failed pump), beyond the pump both systems are separate.
Now you have a lift control issue, usually this is caused by a sticking control valve, sticking unloader valve or something in the draft control spring linkage forcing the lift control into lift position
Do you have any type of repair manual such as I&T or factory service manual, or are you googling and utubing for information on how to make repairs