need help troubleshooting FJ 40/mini truck power steering upgrade (7 Viewers)

[topsljack]

Hello everyone!

I’m jumping in on what is obviously a very old topic in general for FJ 40s, but this is something specific enough that I need some real tech advice from the best people on the Internet and that’s the folks on ih8mud!

What I have is a 1977FJ 40, I got the power steering conversion kit from Cruiser Outfitters, and a Toyota 4runner power steering box (1981-1985, 4wd). The conversion kit, of course, comes with a pump, mounting bracket and the high-pressure hose.

So, here follows the tale of probable idiocy, seeing as I don’t necessarily know my way around power steering. Got everything installed, read through the Toyota 4-runner manuals to find out which was the high-pressure and low pressure ports on the gearbox, (I think I got it right). If anybody can confirm the one that I believe was the high-pressure line is the one that’s on the inside lower port. I could post pictures when I get to a computer if that would help.

In any case, got it all installed and did the old-school form of bleed, which was probably a bad idea. That’s where of course you turn the wheel back-and-forth with a vehicle jacked up about 20 times and then turn it on and then do the bleed again with a vehicle running while turning the wheel back-and-forthand then put it all back together. In the next go around of course I’ll do a vacuum bleed just to make sure.

The whole thing worked brilliantly for about two days. At one point, though when I came home, I made a hard right turn on the steering wheel to the stops as I was prepping to park and suddenly I could not turn the vehicle left without great effort. I figured that that was probably a bleed problem and I’d overheated the thing and had air in the system because I didn’t do a great job at that bleed I guess (or something else). So when testing it today I checked tye fluid, did another bleed, and in the middle of the bleed process, the high pressure line actually burst at the crimp. So now I know I either had a really bad high-pressure line or I really screwed this thing up.

I could use some advice!

 

[topsljack]

More images, one of the question on high-low and the other showing the burst hose, which was new!

 

[Camotubebender]

I don't think air in the system would cause that but maybe a defective steering gearbox? Probably be best to return that gearbox but you could try another hose and see what happens

 

[Engineer8000]

Not sure of your box exactly but on other early Toyota PS gears the return hose is up front as you show it. The pressure control is usually part of the pump. Could be that is not working, or the hose was not crimped correctly.

 

[Skreddy]

I thought the ports were different sizes so you couldn’t mix them up?

As for bleeding, the way you did it is perfectly fine. There’s no reason to need to vacuum bleed power steering, I’m not even sure how you would.

I’d be suspecting a bad pump or box since it locked up one way. Maybe the pressure relief valve was installed incorrectly (or not at all?).

 

[aztoyman]

Your method of bleeding the system was fine. If you did have air in the system, the pump would whine and you would have aerated oil.

IDK if that year box has the same size ports or not. My 86 and 88 box have different size inlet and return ports. I'd think if you had them reversed, it wouldn't have worked well for two days but, maybe not?

The pump relief should handle a pressure spike. It limits pressure when you hit the steering stops. Holding it against the stop isn't good because of the strain and heat generated but it shouldn't blow a hose.

If it was mine, I would verify for sure which port is which. If it is correct, and the gearbox is NOT binding up both directions with the wheels off the ground, I would try another hose. I would also check pressure to ensure the pump relief is functioning properly. Hopefully it was just a bad hose.

If the steering box did feel crunchy or binds up when tested, I'd be looking at the box before I went further. There may be debris in the system at this point. So even if you get another box, flush it out and check the pump.

 

[topsljack]

I thought the ports were different sizes so you couldn’t mix them up?

As for bleeding, the way you did it is perfectly fine. There’s no reason to need to vacuum bleed power steering, I’m not even sure how you would.

I’d be suspecting a bad pump or box since it locked up one way. Maybe the pressure relief valve was installed incorrectly (or not at all?).

on this pump, both of the ports seem to be the same size. Your point about the pressure relief valve is very interesting. The pump is from JTOutfitters & the gearbox is from an overseas merchant and it’s not necessarily the same kind of 4-runner four-wheel-drive power steering gearbox that most people use for their conversions. As such it did not cost that much and perhaps there’s something defective with it. I think it’s best not to underestimate that and I’ll go ahead and purchase a domestically refurbished gearbox that is the model most people use. Definitely better to be safe than sorry! I should probably decide if I should consider a different pump!

 

[topsljack]

Your method of bleeding the system was fine. If you did have air in the system, the pump would whine and you would have aerated oil.

IDK if that year box has the same size ports or not. My 86 and 88 box have different size inlet and return ports. I'd think if you had them reversed, it wouldn't have worked well for two days but, maybe not?

The pump relief should handle a pressure spike. It limits pressure when you hit the steering stops. Holding it against the stop isn't good because of the strain and heat generated but it shouldn't blow a hose.

If it was mine, I would verify for sure which port is which. If it is correct, and the gearbox is NOT binding up both directions with the wheels off the ground, I would try another hose. I would also check pressure to ensure the pump relief is functioning properly. Hopefully it was just a bad hose.

If the steering box did feel crunchy or binds up when tested, I'd be looking at the box before I went further. There may be debris in the system at this point. So even if you get another box, flush it out and check the pump.

there is no sense of grinding, as I was turning the wheel back-and-forth with the wheels off the ground yesterday, and it was going both directions, but whatever happened to make it so that I had to attempt to re-bleed when it did power assist to the right and not to the left a couple nights ago has me concerned, certainly. After only a day and a half of use, I can say that the power steering fluid smelled a little burnt to me which has me also concerned. I think that could be due to excessive heat from air in the system, but maybe also something else.

 

[Skreddy]

on this pump, both of the ports seem to be the same size. Your point about the pressure relief valve is very interesting. The pump is from JTOutfitters & the gearbox is from an overseas merchant and it’s not necessarily the same kind of 4-runner four-wheel-drive power steering gearbox that most people use for their conversions. As such it did not cost that much and perhaps there’s something defective with it. I think it’s best not to underestimate that and I’ll go ahead and purchase a domestically refurbished gearbox that is the model most people use. Definitely better to be safe than sorry! I should probably decide if I should consider a different pump!

If you look at the pic that shows your blown hose, you can see it looks like the flare nuts may be the same size, but the hose metal ends are different. The high pressure line side looks slightly smaller. So, if it were in the low side, the nut might thread but you’d have a sloppy hose fit. Also, the low shouldn’t fit into the high side because the hole would be too small.

Again, I don’t think you had a bleeding problem. Power steering systems are relatively simple in that aspect and they don’t “unbleed” unless you ran it low on fluid and it sucked air. As said, you can hear it when they have air or not enough fluid in them.