1st gen power steering issue

[Dibs01]

Great Forum!
Looking for a solution to a very interesting problem...I recent puchased a 1989 4Runner with 87,000 original miles and gutted the interior, replacing upholstery, etc..
On to the issue
The older gentleman I purchaed it from indicated that he was, for some reason, going through a bit too much power steering fluid.
My thought was, it really shouldn't be using ANY other than what is first added when doing a fluid change. Nevertheless, I bought it anyway, and can't seem to figure out why, when I add fluid to the power steering fluid resevoir, the truck smokes for a bit(very short time, like 20 seconds). I check the level of both motor oil and PS res, and both are at the full line....
Now for the interesting part....after running around the block to test and upon return, I find the PS Res empty and motor oil overfilled now!!!
Not sure what to make of this!!
Any help would be greatly appreciated

 

[slacker]

this system uses ATF .. not "power steering fluid" ... I will leak if your using psf


.

 

[KidVermicious]

after running around the block to test and upon return, I find the PS Res empty and motor oil overfilled now!!!

A quick look at your power steering system will reveal that there is no way these two things are related. Your power steering pump has a fluid reservoir, and there is a line going from the reservoir to the pump, a line from the pump to the steering box down on the frame, and a return line from the steering box to the fluid reservoir. It never goes anywhere that your PS fluid could be mixing with the motor oil. No chance.

I think you have a PS leak, and that's where your fluid is going. As slacker notes, you're supposed to use ATF in these PS systems - if you've been filling with power steering fluid, stop doing that. Flush the system well with ATF, and do it after a day of driving. If you're still losing fluid, chase down and repair the leak.

The issue of overfilled motor oil is concerning - is the oil clean, or a milky color?

 

[fastgtfairlane]

what type of atf to use?

 

[Red88TopangaCa]

What could happen if one were to use psf instead of atf?

 

[fourwd1]

This is simple. There are 2 vacuum hoses going to a VSV on the PS pump. This is to increase the idle RPMs when the PS loads down the engine, like when you turn the wheel wile sitting still.
The rubber diaphragm in the VSV has a hole in it and the PS fluid is being sucked into the engine and being burned. That explains the loss of fluid and exhaust.

 

[nevada]

this system uses ATF .. not "power steering fluid" ... I will leak if your using psf


.

not true.

What could happen if one were to use psf instead of atf?

nothing.

This is simple. There are 2 vacuum hoses going to a VSV on the PS pump. This is to increase the idle RPMs when the PS loads down the engine, like when you turn the wheel wile sitting still.
The rubber diaphragm in the VSV has a hole in it and the PS fluid is being sucked into the engine and being burned. That explains the loss of fluid and exhaust.

this. the VSV is bad.

 

[slacker]

Originally Posted by slacker View Post
this system uses ATF .. not "power steering fluid" ... I will leak if your using psf

not true.

huh .... so the 6 + leaking pumps I have had in my shop with p/s fluid in them was fictitious ?
and then just simply bleeding the system and replacing with ATF was just a figment of my imagination ?
and the fact that these trucks to date still have no leaks in the system .

I guess you know what you know , and I know better , check the manual even states to use ATF and NOT p/s fluid ...

 

[9494runner]

huh .... so the 6 + leaking pumps I have had in my shop with p/s fluid in them was fictitious ?
and then just simply bleeding the system and replacing with ATF was just a figment of my imagination ?
and the fact that these trucks to date still have no leaks in the system .

I guess you know what you know , and I know better , check the manual even states to use ATF and NOT p/s fluid ...

I have to agree. Everything I have read about PSF vs ATF in our trucks has stated that PSF will either leak or cause the pump to not run as smooth even fail. IH8Mud has a lengthy thread arguing both ways, but consensus looks to be toward ATF to prevent the creaks and moans from the system as well as prevent/fix minor minor leaks. Some people tossed around hydraulic fluid as a replacement since it is basically is a hydraulic pump; IMO ATF or you can bandaid with PSF but flush it out ASAP.

power steering fluid ok instead of ATF?? | IH8MUD Forum

I would check out that VSV leak if you are loosing fluid out of your PS system. The vacuum lines would be the only way possible to really draw fluid into your motor otherwise you'd see it on the floor

 

[slacker]

what type of atf to use?

sorry , missed your post ...
any dextron ATF - I , II , III ,IV , V or even VI just don't use a synthetic


.

 

[fastgtfairlane]

thankyou!