I need some advice to correct a problem on my 1990 Diesel Ford F250- super cab. Just recently and without much warning, it is *very* difficult to turn to the right... turning left is smooth, but to the right ( past straight ahead) requires very hard wrestling with the steering wheel. With a lot of effort it barely rotates an inch, then with more wrestling, another inch. It will eventually get to the full two steering wheel turns to the right, but this is not drivable at all.
The smoking gun is the steering box, but has anyone heard of this symptom ( ok in one direction bad in another).

some other observations:

-plenty of power steering fluid (actually 3/4 inch overfilled), and turning to the left works fine with the engine running.(?thus no pump problem?)

-taking weight off the right wheel(jacking it up) makes it easy to turn (with enging running), even when there is some contact with the ground. Adding more weight back on the tire makes the turning right difficult again. (?thus no obstruction in the linkage?)


--revving the enging doesnt seem to help much.(?not a pump problem?)

--I seemed that there were a couple of times that the steering to the right got 'fixed' momentarily, but I am not certain about this.

--I have not done any adjustments to any steering components.



I need to resolve this as I cant drive this again until fixed and dont want to fix the wrong thing.

Late update: Someone suggested that it might be the king pins on the right wheel... he said to disconnect the steering arm from the wheel and then turn the tire by hand... if bad it will not turn in some portion of the turn. Havent done this yet

Help! and Thanks

 

Had the same problem on my '90 F250HD, which developed about 150 miles into a 950 mile trip! I started by replacing the steering box with a rebuilt unit and it didn't change a thing. Replaced the steering pump, and all was well again. I used a heavy duty pump that I purchased from Four Wheel Parts Wholesalers, but at this exact moment, I can't remember who manufactured the thing... cost about $130.00. The steering box was about $50.00.

 

Thanks Rondog. Is there any reason, based on the design of the pump, that that the pump would be able to turn left but not right? As further confirmation of the pump being bad, should the problem go away if the engine is revved high (while stationary and turning left and right).? Was there any insight offered by the parts dealer or others that could explain what inside the pump had gone wrong?

Is there any specific procedure to refill the system with Powersteering fluid when reassembling?...eg. to avoid air in the system?

 

Instead of kingpins I believe 1990 had ball joints, at least my 1990 F250HD does. You can take the tie rod end off easy enough. When mine go bad though the wheel gets loose like a bad wheel bearing. You can shake it and determine if it's the top or bottom but I always change both at the same time. I would think it is in the steering gearbox though on the worm gear. Or it could possibly have a hydraulic problem. I can't see where the pump could differentiate which side you are turning. And while the ball joints could be binding, they should show resistance turning both ways. more than likely lifting the tire wouldn't affect the joints but it could be possible if they have been gone for awhile. Someone may know more about the design of the pump and can help. Maybe it pushes one way and pulls another so the hydraulics may have a seal out. The pump is definitely easier to change. Once you get it turned all the way to the right, is the any resistance coming back to center? And turned all the way left does the resistance begin as soon as you go right or after straightening the wheels. If it is in the steering gearbox on the worm gear (bad teeth) then it should have a problem when the tires at at the same position. If it is in the pump it might show up when you are locked to the left and start returning to the right. This is theoretical though. If the steering gear is just too loose, it'd bind one way too and probably all the way. Help should be on the way soon because I know alot of people on here drive big rigs and are bound to have experience. If I had to drive it though, I'd take chance. I tend to think it'd be in the gearbox and if you can do the work that part is cheaper. But the pump is easier to replace... Good luck and let us know if something fixes it. I may have the same problem next week.

 

Thanks Tim, your explanations help.
Here are some additional things I did yesterday to help the troubleshooting:
1. Focus on the pump-
From before... turning left or right when the wheels are at center or left of center is smooth. Turning the wheels right of center is where you start getting significant resistance.
The steering wheel will turn approximately 4 full turns, and wheels straight ahead is after two turns from full left , as it should be.
Now the test... with the engine idling and turning hard to the right (after a quarter turn from center it starts getting very tough) I then accelerate the engine to 2000 rpm to see if the increased pump pressure helps... significantly, I really cant tell the difference, It still requires the same high force to turn right. I check the belt to ensure it is working properly, and it is the snuggest belt up front. I watch the belt and pulley while someone else accelerates the engine.... no slippage, the pump pulley clearly accelerates.
>>>>>net conclusion-- probably not the pump because left turns work fine and acclerating the pump does not have any effect. And turning left from the fullest right position is also easy.

2. Focus on ball joints.
Yes this model has two ball joints , not a single kingpin.
Unfortunately my floor jack is not strong enough to lift the vehicle, or one side in the air, however, with just a crank or two lifting the frame slightly, there is a noticeable effect on the abilitiy to turn right.
First I greased all the grease fitting joints in the steering train ( by the pitman arm and at either end of the tie rods. Next I ensured that the linkages were tight by observing their operation when the steering wheel was turned slightly left and right... no slop, everything looked ok; the wheels would start turning with a small movement of the steering wheel.
Next I took some weight off the right front tire by jacking up the frame near there different amounts. At no time was the wheel in the air, but the tire was on gravel which reduced the resistance to turning, I think. With full two pumps of the jack, I could easily turn right one full turn from center ( the second full turn was very hard again); previously I encountered resistance at a quarter turn to the right. With 6 full pumps, I was able to turn the steering wheel the full 4 turns, left and right with no problem. In this last test the weight on the right front tire was lower because of the jack and the left front tire had no help from a jack ( in fact it probably had a higher load because the other side was slightly jacked up). To avoid jumping to a possibly incorrect solution, I repeated this test on the left side... jacking up the left side and running the same test. I wanted to off load the left side and load up the right side to see if there was any different result. The results were the same... the steering wheel turned easier depending on how much I jacked up the jack. With 6 pumps, there was no resistance on the steering for the 4 full turns left and right.
>>>> tenative conclusion--not a ball joint problem because the wheels turned easily wether I had a heavy load on one side or the other- I would have expected difficulty in turning when the jack was on one side, but not the other if one side had bad ball joints. I concluded that with the jack in operation on either side, it required less total force to turn the wheels, so they were able to turn more easily as I pumped the jack. This pointed back to the steering box as the possible culprit.
Does this sound right to you guys?
Now my question... can I do further troubleshooting to isolate it to the steering box with only the simple tools I have?
It appears that the adjusting screw on the steering box has never been adjusted... would it be appropriate to try adujusting it and seeing the result? which way should I turn the screw and how much can it be adjusted? when will I know I am done or made it worse short of driving it?

ps. there are no leaks from the steering box or pump... and I have about 140kmiles on the vehicle.

thanks a lot for your help.

 

tim, as to your questions:


Once you get it turned all the way to the right, is the any resistance coming back to center?
<<<pjw no it turns easily back to the center from a full right turn >>>

And turned all the way left does the resistance begin as soon as you go right or after straightening the wheels.
<<<pjw -- gets hard after straightening the wheels...the first 2- 2.5 turns are easy >>>


If it is in the steering gearbox on the worm gear (bad teeth) then it should have a problem when the tires at at the same position.
<<<pjw For a given jack support (none to full) it is at the same position of the wheels >>>

If it is in the pump it might show up when you are locked to the left and start returning to the right.
<<<pjw when locked to the left, it will always be easy to turn the next two full turns to the right, once the wheels are centered, and another quarter turn, it binds (no offload on the jack) >>>
This is theoretical though. If the steering gear is just too loose, it'd bind one way too and probably all the way
<<<pjw I dont understand this comment Tim; what condition in the steering box would correlate to the response I see in steering? Its as if the steering box encounters more internal resistance when turning right of center and cant overcome it unless the force at the tires is lessened (eg. by the jack).
It would be very helpful to get an explanation or reference to how the haudralic assist works in the steering box... eg. is there more pressure applied as the steering wheel is turned further to the right or left?, or is it the same assist regardless of how far the steering wheel is turned?
Jumping to a particular solution... if the hydraulic pressure is basically constant throughout the full travel of the steering wheel, then it would appear that the worm gear is binding somewhat in right turns ... Question, does turning the worm gear adjusting screw affect both right and left turns? ... ie can correcting a right turn binding lead to a problem (looseness) when turning left??? >>>

 

Tim... something ate my replys in my previous response, so here is a resubmit of that same reply:

tim, as to your questions:


TTT...Once you get it turned all the way to the right, is the any resistance coming back to center?
...pjw no it turns easily back to the center from a full right turn

TTT...And turned all the way left does the resistance begin as soon as you go right or after straightening the wheels.
pjw -- gets hard after straightening the wheels...the first 2- 2.5 turns are easy

TTT...
If it is in the steering gearbox on the worm gear (bad teeth) then it should have a problem when the tires at at the same position.

...pjw For a given jack support (none to full) it is at the same position of the wheels
TTT...
If it is in the pump it might show up when you are locked to the left and start returning to the right.

...pjw when locked to the left, it will always be easy to turn the next two full turns to the right, once the wheels are centered, and another quarter turn, it binds (no offload on the jack)

TTT...
This is theoretical though. If the steering gear is just too loose, it'd bind one way too and probably all the way

...pjw I dont understand this comment Tim; what condition in the steering box would correlate to the response I see in steering? Its as if the steering box encounters more internal resistance when turning right of center and cant overcome it unless the force at the tires is lessened (eg. by the jack).
It would be very helpful to get an explanation or reference to how the haudralic assist works in the steering box... eg. is there more pressure applied as the steering wheel is turned further to the right or left?, or is it the same assist regardless of how far the steering wheel is turned?
Jumping to a particular solution... if the hydraulic pressure is basically constant throughout the full travel of the steering wheel, then it would appear that the worm gear is binding somewhat in right turns ... Question, does turning the worm gear adjusting screw affect both right and left turns? ... ie can correcting a right turn binding lead to a problem (looseness) when turning left???

 

There is a procedure for tightening the steering gear in Haynes manual. I've recommended FixitCDs manual from eBay too but I have been informed that they don't begin until 1992. I only have a cd for 2001. In it a complete teardown and rebuild is described. The steering gear has a worm gear and several ball bearings. I've had one apart before that is similar but From a '70's Ford 3000 farm tractor. The dealer didn't like rebuilding it after I took it apart. I did not have any instructions or a manual for it. The 1992 cd should describe your steering gear but it may have different specifications if you're interested.

You can check the gear by removing the pitman arm from the gear. You probably won't have much resistance because you've already demonstrated that by lifting the tires. My 2001 cd tells to check the hydraulic valve by driving and then turning off the engine. However, you already know that you have resistance with the engine off (I think). So I would still think that your problem is in the gearbox.

To adjust the gearbox (Haynes for 1980-1996)
1. Remove the pitman arm and remove the horn pad to gain access to the steering wheel retaining nut. Disconnect and plug the fluid return line at the reservoir.
2. Place the fluid return line in a container and turn the steering wheel lock to lock several times to discharge the fluid.
3. Turn the shaft back 45 degrees from the left stop and attach a torque wrench calibrated in inch-pounds to the steering wheel nut.
4. Rotate the steering gear about 1/8 turn and then move it back across center several times. Loosen the adjuster locknut and turn the adjuster screw until the specified torque reading is reached when the steering gear is rotated through the center position.
5. Hold the screw and tighten the locknut.
6. Replace pitman arm and fluid lines. Fill with fluid. Replace horn cover etc.

I have sortened it a little from Haynes and they do include pictures showing locations etc. This adjustment should take play out of the steering wheel. I do not think it will correct your problem. If you loosen or tighten the gear I do believe your problem will be worse. Normally, you tighten it to replace slack. Loosening will reduce effort if steering is too stiff but I'd just change the pump.

If your gear is similar to the one I looked at on cd, your problem will be the worm gear or ball bearings (20-30 of them!). I'd replace it with a rebuilt unit. You can still remove the pitman arm to check it. In the rebuild section on the cd, there are other adjustments to get it to specs. If it ran right before though it shouldn't need readjusting there. I can send more info on that but it is for a newer truck and probably won't help you anyway. I'd get the 1992 or earliest version of the cd at eBay. There's not much differences in the models, mechanically. I believe that the ball bearings have worn, or some missing. I could be wrong though. I'm just trying to help by providing what I can find. Good luck.

 

Hi Tim and thanks so much for the explanations.

As to a few of your comments:

TE===
My 2001 cd tells to check the hydraulic valve by driving and then turning off the engine. However, you already know that you have resistance with the engine off (I think). So I would still think that your problem is in the gearbox.
PJW===Where is the hydraulic valve located... in the steering box? Also, with this test, can I assume you are driving in an open area (eg. large empty parking lot), trying to turn right, meeting strong resistance, and then shutting off the engine to see if there is a significant drop in assist while trying to turn right. Is this correct? If there is little change with the engine on or off, this would indicate some hydraulic valving problem (ie. it is always getting almost no hydraulic assist when turning hard right).


TE===
Loosening will reduce effort if steering is too stiff but I'd just change the pump.
PJW=== do you really mean replace the power steering pump here? Elsewhere the main suggestion seems to be replace the steering gear box.


TE===
You can check the gear by removing the pitman arm from the gear.
PJW=== Does this mean that you turn the steering wheel without the pitman arm attached (can you just disconnect the pitman arm to idler arm connection, which may be easier?) so you can see if there is increased drag in the gear as you turn right, compared to turning left? Is this done with and without the engine running/

Bottom line, I conclude that you say to replace only the steering gear box (rebuilt unit), is that correct? any suggestions on an economical source for the part?
Thanks again,
paul

 

Tim,
I was toying with the idea of

does the diagram of the wormgear/ball bearings show how the adjuster bolt works? Im guessing that the adjuster bolt raises and lowers a 'cage' that holds the ball bearings, either bringing the ***** closer to the gear (tightening_ or farther away (loosening the steering). I was hoping that the solution would be to loosen the adjusting bolt slightly enough to reduce the apparent binding that is happening on turns to the right. Of course the potentially increased looseness would have to be checked (there is virtually no looseness now).
comments ?

 

No, it did not show that. I don't fully understand what the adjuster bolt adjusts. If your steering was fine before, I wouldn't think loosening will help. I think the ball bearings at some point have a flat side or some or missing. On the tractor gear I took apart, some were similar to a bad u-joint. If they don't roll they will wear something or eventually disintegrate. I saw rust looking particles as in a bad u-joint. If you loosen too much the ***** can jump track and if they have already worn too much, no amount of adjusting will save you much. You'll still have to replace the gear. I can not say if adjusting will give you more or less time. I can not be certain your gear is bad either. I can only suspect it to be bad. I just saw that you had a prior message so I'll try to answer your questions there.

The valve is part of the steering gear where "in" fluid line is connected inside of gearbox. I did not read everything in the rebuild well. It would make more sense if I had one apart. I don't understand how it "assists" either.

I didn't mean any confusion by mentioning the pump. Personally, I can not see any reason to loosen the gear, unless it was recently overtightened. Because if it was adjusted properly at some point and worked fine, it can only wear and get looser, not tighter. I generally respond late and don't communicate effectively at times. Sometimes my thinking even gets way off if I've been up to long or get distracted. I never intend to disrespect anyone because there's more that I don't know than what I do know.

If my truck steered too tight I would change the pump. However, your's is binding somewhere. It is not tight all the way through.

If my truck was exhibiting the same symptoms as yours, I'd change the steering gearbox. Sometimes, I am wrong. I can not guarantee that this will fix it. I have changed gear boxes before. Generally, I had a used one laying around or on a junk truck. I changed several manual steering trucks to power steering. I have bought rebuilt units at a local parts store but it was for early '80's and I can't remember the price. If I get a chance I'll look around online and let you know. I also looked in some 4x4 mags laying around. I used to see a vendor advertise in them but I couldn't find the ad. Most 4x4 readers want lifted trucks and may need an upgraded or larger gear that would be significantly higher. I'll get back tomorrow with some prices if possible. Today or tonight one has been long.

 

O'Reilley Auto Parts listed only one but I input my truck info. A1 Remanufactured Steering Gear by Cardone Industries 27-7516 @$169.99 + $90 core http://www.oreillyauto.com/index.html Click on Part Inquiry. They'll direct you to the nearest store then get truck info. The site then tells if the part is available at your local store or you call call to order. I haven't checked around much but they generally offer me decent parts/prices. I buy parts from several sources so I'm not exclusive to them and I don't own any of their stock.

 

Thanks Tim,

Well, I'm going to take the dive tomorrow and replace the steering gear. I am getting a A1 Cardone part from Kragen auto through their online parts supplier : partsamerica. $169, no delivery charge, local pickup; I was a little too concerned about getting a used one as it would have to be at least 7 years old (my steering gear was unchanged from 1980-1996.
In talking with tech support from partsamerica on the phone, the guy indicated that as you turn the steering wheel, the pressure applied to the gear increases, apparently the gear needs more and more assist as you turn. Given that my left turns work flawlessly and the right turn meets resistance after a quarter turn (less if you take some load off the steering) it seemed pretty conclusive that something was happening in the hydraulic valving inside the gear box.
Now we will see if the theory measures up to the reality.... or maybe I will get lucky and fix the 'real' problem with the gear by exchanging it. Ill let you know the outcome.

thanks again ,
paul

 

Good luck. I don't remember paying that much but sometimes I used a salvage part. I haven't changed one in over 12 years either though. But my '90 F250 could use a tighter front end. I've been looking for a replacement truck instead of parts. I'll stick with F250.

 

the repair job is rescheduled for sat afternoon, the fishing and diving is just too good right now