Power Steering Issue

[Red90runner]

Hello to all the Toyota Heads,

I just got a 90 4Runner 4x4 Manual SR5 (pics to come) and I'm starting to go through it. I have read the posts on bleeding of the PS system and understand the proper method now. I know this might be an elementary question, however I need to ask. Is it correct to assume that the PS system will NOT function until bled properly and completely. My truck had no PS belt when I bought it but the pulley spun, so I bought the belt, put fluid in and started the process of bleeding. There are no leaks. It was as if there was no power steering what so ever during the bleeding I attempted. I tried with the truck on, but just got foam. Is this normal until is it bled properly?

Thanks for you efforts and knowledge base.

 

[Jukelemon]

I guess I am not following you.

How was the PS NOT hooked up? Are you saying you were running a Power Steering gear box without using fluid/a pump?

No, a properly bled system should not foam. Foam means air and that is no good.

Just for clarity's sake, what do you call a proper way to bleed?

 

[bkgee]

i had foam in my PS reservoir when it was running low. i filled it up properly, and the foam disappeared. the foam may actually mean that the unit is working properly, just needs fluid..?

 

[raydouble]

I'm sure the steering gear has an air bubble trapped in it.
It should clear itself with proper fluid level and working the wheel back and forth.

 

[Red90runner]

There was no belt when I got it. Everything else was connected, just no belt. The guy said it broke. I put on the belt, put fluid in the reservoir, but when you turn the wheel back and forth it is damn hard like no power steering, and lots of foam.

 

[Red90runner]

Hi, as I now understand it, you must jack up the front, disconnect the return and plug the reservoir. Then fill up fluid and with the truck off an steering unlocked turn stop to stop until clean fluid runs out the return hose, while monitoring the reservoir to make sure the fluid level does not go to low. Then reconnect the return hose and top it off. Is this correct? do you leave the reservoir cap off for all this? thanks

 

[Jukelemon]

In the past, I have jacked up the front to relieve the stress on the gear box.

Get a friend, remove the reservoir cap, and monitor the fluid when your friend is going back and forth (stop to stop).

I have never disconnected anything in the past. It is a pretty simple flow circuit and short to boot. Air should be released/should bleed via gravity/via reservoir with cap off.

The fluid is also a coolant to the steering box. It can overheat and damage the box. That is why I asked about running it without fluid/belt.

 

[Red90runner]

I went through the jacked up bleeding routine. It would not flow fluid through the return hose without the pulley spinning. I did it with the truck idling and cleared the line with clean fluid. Had a friend crank it while I kept the reservoir clean and full. Put everything back together but still no power steering. The fluid is not foamy and there are no leaks but I'm baffled. I don't know how long it ran with out the belt or what the fluid condition was before I got it. Is there a way to tell if the steering box is messed up. I does steer fine just no PS. Any thoughts or suggestions are appreciated.

 

[hawkeye]

You could use some upper boy workout anyway Sorry I am no help.

 

[raydouble]

I went through the jacked up bleeding routine. It would not flow fluid through the return hose without the pulley spinning.

Since in sounds like you've got fluid flowing, I would think it might just be bypassing at the steering gear.

As Jukelemon said "The fluid is also a coolant to the steering box. It can overheat and damage the box."

I think it has probably been overheated and damaged internally....
link = http://www.ncttora.com/fsm/1993/steering/13gearh.pdf

I also think the pump should be fine since it was just sitting idle the whole time.

You might try to bleed the fluid from the steering gear via the bleeder, but I'm not sure it's going to do anything for ya.

 

[GRM]

I have always bled the box with the engine running. Its better to turn lock to lock with the front tires off the ground, but I rarely do. I turn lock to lock about 30 times, keeping the fluid topped on.

I only take off the return line when I want to flush out the fluid. Another trick I use to flush out the box is to put a 6" piece of hose on the end of a turkey baster, and suck the fluid out of the reservoir. This gets about 1/3 of the fluid out. Pull the fluid out, top it off with new fluid, and bleed the box. Repeat this process about 10 times to get about 85% of the old fluid out.

Another thing I'd like to add, which has nothing to do with your problem is you may want to consider flushing out the fluid and swapping in sta-lube power steering fluid.

From my experience on the trail, on a hot summer day I'm the only one not having my fluid boil. Sta-lube has a higher flash-point than most other fluids. Its actually very close to redline fluid, but without the high cost.

 

[Jukelemon]

I went through the jacked up bleeding routine. It would not flow fluid through the return hose without the pulley spinning. I did it with the truck idling and cleared the line with clean fluid. Had a friend crank it while I kept the reservoir clean and full. Put everything back together but still no power steering. The fluid is not foamy and there are no leaks but I'm baffled. I don't know how long it ran with out the belt or what the fluid condition was before I got it. Is there a way to tell if the steering box is messed up. I does steer fine just no PS. Any thoughts or suggestions are appreciated.

Man, I dont follow you. What do you mean there is no fluid flowing without the pulley spinning?

The only pulley is on the pump and the fact that you just said it would not return without the pulley tells me that you were running it without the belt/pump trying to bleed a hydraulic system. Is this true?

Like I mentioned before, it is a very simple circuit. Pumps to the steering box and then pressure sends fluid back via the return. If the PS does not work, you either have a bad pump (very possible depending upon the abuse and mileage) or a bad gear box (also very possibly if someone ran it without fluid). Really not much else if there are no leaks. And even if there are leaks, you would have assistance (power steering)-just not the full assistance.

I am betting you have a bad PS pump and you do not have enough pressure to properly pressurize the gear box.

 

[BeetleWarrior]

Are the two vacuum lines hooked up to the top of the pump? My understanding is it needs the vacuum at idle - low speed to allow the pump to work better....

 

[WarDamnEagle]

Another thing I'd like to add, which has nothing to do with your problem is you may want to consider flushing out the fluid and swapping in sta-lube power steering fluid.

From my experience on the trail, on a hot summer day I'm the only one not having my fluid boil. Sta-lube has a higher flash-point than most other fluids. Its actually very close to redline fluid, but without the high cost.

I'm sure this fluid will probably work OK but your power steering system is supposed to run on ATF and not power steering fluid. Check your owner's manual to verify but I would bet on it. Both my 1985 4Runner and my 1997 FZJ80 call for ATF for the power steering. Not sure that's causing your problems but you should get the correct fluid in there.

 

[Red90runner]

Thanks for all help and comments...Hope everyones holidays were great.

Well I'm back at it but I got hit with another issue so the PS while it has improved a bit it still not resolved. I think the air bubble is in the steering gear. I would love any advise on getting it out if there. Does the steering gear have a bleeder valve? The PS comes and goes. Funny it works best at idle. My new issue is a number 5 cylinder with 30psi compression. I am waiting for my leak down tester to come back and praying it's a bent or stuck valve. It has no blow-by out the oil cap. Wish me luck...and thanks for all the support.

 

[Jukelemon]

Find the steepest hill in your neck of the woods i.e. try to get that truck as vertical and safe as possible.
Need to use gravity as your friend. Lock to Lock as many times as it takes to get the air out.

I have never heard of anyone bleeding a steering gear box but maybe...

 

[KLF]

Toyota specifies Dextron ATF in their PS systems, it says so right on the cap. My son made the mistake of putting regular PS fluid in his system recently, and now he has a bad leak at the sector shaft on the box, and a bad groan from the pump.

Jacking the truck up and cycling the system back and forth while the engine is idling should remove all the air from the system.

The vacuum lines that connect to the pump monitor the pressure in the system, all they do is bump the idle up if there is a high pressure demand on the system (such as trying to turn at full lock while at an idle).

It's much worse on the vane pump to run the system without fluid than the steering box. Actually, I don't think it will hurt the box, it will just be hard to steer. But with no fluid in the pump, the "vanes" will not be lubricated and will wear and score the cavity of the pump housing. It's hard to describe but if you looked inside a pump you'd understand. Very few pumps can tolerate being run dry, and the vane-style pump that Toyota uses is one of them.

I have a couple spare pumps from a 22RE, but it sounds like you have a V6. Also sounds like you will be replacing the head gasket.

 

[Red90runner]

Find the steepest hill in your neck of the woods i.e. try to get that truck as vertical and safe as possible.
Need to use gravity as your friend. Lock to Lock as many times as it takes to get the air out.

I have never heard of anyone bleeding a steering gear box but maybe...

I'll try that. I need to take the pump out anyway and I'm gonna drain the system and flush it out with DEXTRON. I got just the hill on Mt Baldy

 

[Red90runner]

Toyota specifies Dextron ATF in their PS systems, it says so right on the cap. My son made the mistake of putting regular PS fluid in his system recently, and now he has a bad leak at the sector shaft on the box, and a bad groan from the pump.

Jacking the truck up and cycling the system back and forth while the engine is idling should remove all the air from the system.

The vacuum lines that connect to the pump monitor the pressure in the system, all they do is bump the idle up if there is a high pressure demand on the system (such as trying to turn at full lock while at an idle).

It's much worse on the vane pump to run the system without fluid than the steering box. Actually, I don't think it will hurt the box, it will just be hard to steer. But with no fluid in the pump, the "vanes" will not be lubricated and will wear and score the cavity of the pump housing. It's hard to describe but if you looked inside a pump you'd understand. Very few pumps can tolerate being run dry, and the vane-style pump that Toyota uses is one of them.

I have a couple spare pumps from a 22RE, but it sounds like you have a V6. Also sounds like you will be replacing the head gasket.

Thanks for the knowledge. I will be replacing the Head Gasket on that side, along with the Exhaust Manifold, Valve cover, Intake Manifold, and Oil pan gasket. Also the Timing belt, tensioner and idler. I figure it has 66K and since I'm gonna be deep in there might as well do some preventative stuff. Wish me luck.