How to bleed steering system ford 3910?

   / How to bleed steering system ford 3910? #1  

mrchicken

New member
Joined
Dec 4, 2012
Messages
5
Location
TN
Tractor
Ford 3910
Got a ford 3910 1988 model with a steering issue. Replaced leaky power steering hydraulic cylinder, worked good for about an hour then the gearbox at the end of the steering wheel shaft started leaking. Bad gasket. Replaced gasket and tractor worked great for about 5 minutes. Then the steering wheel got hard to turn and locked up. Shut it down for a couple minutes. Cranked back up and it worked fine for about 2 minutes then locked up again. Limped it to the barn. It has been suggested that I bleed the power steering system. Any suggestions on how to do this? Thanks!
 
   / How to bleed steering system ford 3910? #2  
I believe most hyd systems are self bleeding as you cycle the cyl.

As you move the cyl rod, and piston, the fluid flows in and out as you steer, and if there is any air, it will also flow out the fluid path to tank.
 
   / How to bleed steering system ford 3910?
  • Thread Starter
#3  
JJ,
That is what I thought too. Had a couple people say I should have left the connections loose after the gasket repair to allow the air to escape. Hope I haven't burnt anything up. 2 mechanics (not tractor guys) have said it sounds like a vapor lock problem, bleed the system.
 
   / How to bleed steering system ford 3910? #4  
When you get to the end of wheel travel does the power steering pump begins to squeal. That means that fluid and air is flowing past the relief valve.

Cycle the steering fully, left and right.
 
   / How to bleed steering system ford 3910?
  • Thread Starter
#5  
When you get to the end of wheel travel does the power steering pump begins to squeal. That means that fluid and air is flowing past the relief valve.

Cycle the steering fully, left and right.

Got er cranked up and cycled the steering full right, let it go 15-20 seconds. Cranked full left. Let it go 15-20 seconds. Didnt squeal that I could hear...(in barn so motor was pretty loud) When I went to crank back to right, steering was sticking. Got it to center, left it for about 3 seconds and it locked up.
Shut down tractor.
Checked fluid level....1/4" below Full and running out of the pump/res fill cap.

Cranked it up with the fill cap off the pump res.....too dark to see if the return line was pumping back into the pump/res.

Got no idea what to do next. :mad:
 
   / How to bleed steering system ford 3910? #6  
It almost sounds like you maybe used the wrong fluid. It's working when the fluid is cold, but then heats up and can't hold pressure.

Just a thought.
 
   / How to bleed steering system ford 3910?
  • Thread Starter
#7  
It almost sounds like you maybe used the wrong fluid. It's working when the fluid is cold, but then heats up and can't hold pressure.

Just a thought.

Same fluid as always. Is it possible I got some dirt in the pump when changing the gasket and its clogging something up?
 
   / How to bleed steering system ford 3910? #8  
If the fluid was at the proper level with engine off, and is now over flowing the fill cap, then I would suggest you may have a suction leak and introducing air in the fluid causing expansion, and therefore overflow.

Hot fluid will expand, but they allowed for that by the full line on the dip stick.
 
   / How to bleed steering system ford 3910? #9  
Same fluid as always. Is it possible I got some dirt in the pump when changing the gasket and its clogging something up?

By same as always you mean the same as the transmission and the rear end, right?
The 3910 only uses 2 fluids, oil and hydraulic fluid.
You didn't mention the filter that is mounted in the rear of the pump. Have you ever changed it?
 
   / How to bleed steering system ford 3910? #10  
I would check the steering gear box to see if the power assist is leaking into the steering gear section now. Only a gasket separates the two sections. If so, then there is a new issue. Just one thing I would look next. IMO. Good luck.
 
 
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