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How to rebuild a power steering pump on 1H engines

Rob

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Mar 1, 2010
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Garage
Leaking power steering pumps seem to be quite common on the 80. This is not something you should ignore as the pump is gear driven of the crankshaft so if it were to seize due to a lack of oil it could cause serious damage to your engine. The fix is quite simple, all you need to get is a pump rebuild kit part number 04446-60070 for my 97 1HD-FT. This kit comes with all the internal oil seals, o-rings and copper crush washers for the high pressure pipe coming off it and a o-ring for the return pipe. As far as parts go all you need is in the kit. This guide is relevant to all 1H engines including 70 series and 100 series, but as I did this on an 80 it may be 80 specific in some cases.

You will need the following tools: socket set including an assortment of UJs and extensions, a 22mm socket (if you dont have one in your set) and a 17mm 12 sided socket (double hex). A vice is very useful.

The PSP (power steering pump) is located bottom left near the front of the engine. You have 3 access points, through the bonnet using extensions and UJs, through the front left wheel arch (remove plastic flap and turn wheel to the left or remove) and from the bottom (remove the front bash plate, the one near the steering damper).

You can either drain the fluid from the system completly or just disconnect the pipes and catch what comes out. It you wnat to drain it completely you need to disconect the return pipe that goes into the reservoir, see red arrow below.
PS%20resorvoir.bmp

When doing this be prepared to catch any fluid that comes out of the reservoir into a jar or something. Now take the return pipe and pull it out the bottom of the truck and place a container to collect the fluid underneath it. Now get someone to turn the engine on and turn the wheel lock to lock until there is no fluid coming out (best to do this with the vehicle on stands). You need to keep an eye on this as you could cause damage to the pump if you run it too long without fluid.

Once drained you need to disconnect the 2 pipes on the PSP. The one on the top needs a 22mm socket (high pressure) and the one underneath (return) is held in place with 2 bolts, 10mm socket. You will need to unbolt the return pipe from the bracket that holds it in place before removing it from the pump. This is the return pipe:
PS%20return%20pipe.jpg


Now you need to unbolt the pump from the engine. The pump is held in place by 2 bolts, use 14mm sockets (green below). I could only get to these using a spanner as there is not enough space for a socket. Also I have some weird foamy material in between the PSP and the fuel pump so access is difficult. Once you get the bolts out pull the pump out and you should have this in your hands:
15062010081.jpg


Now you can see you you need a 17mm double hex socket. Hold the gear with a pipe wrench (gear wrapped in rag) and unbolt the 17mm double hex nut. Now you need to pull the gear off which was rather difficult as the shaft is in the shape of a cone. Use a soft hammer or equivalent to break it free. Now split the pump by undoing the 3 bolts, 14mm sockets, taking note of how the 2 sides fit together (use match marks).

Now you will have 2 halves, one with the shaft and the other looking like this:
15062010075.jpg

There is one seal inside the half in the above picture but i had great difficulty taking all the bits out so i passed on that. According to the FSM you need to use a hammer (at the time i did not know where the 3rd large o ring went). If you do remove it take note of how the vanes go in, round edges near the outside. Remove the flow control valve, see red above and below

The other half will have a snap ring, just behind where the drive gear was. You will need to remove it in order to remove the shaft and bearing. Be careful not to damage the bearing. Once out the shaft should come out if you tap it with a hammer. You will now see the oil seal, prise it out with a screwdriver and take note of which way round it was. You should now have something like this:
15062010058.jpg


When assembling it you will need to coat all the internal parts with ATF fluid DII or DIII and the oil seal on the shaft needs a film or red rubber grease. If you managed to get the bits out that are below the vanes etc then you need to make sure it all aligns properly using the locating dowel. Once assembled put it back onto the engine and connect the pipes using new o-rings and crush washers. Do not overtighten the small bolts on the return pipe. Now connect the pipe that you disconnected from the reservoir and fill with ATF fluid (DII or DIII). To bleed the system turn the engine on for a few seconds and turn off then top up the fluid. Remember to keep turning the wheels from lock to lock when the engine is off. Once you don't need to keep topping it up let it run for a few minutes turning the wheels lock to lock to get all the air out of the system. When the fluid in the reservoir is clear (not foamy) then you know you got all the air out. Keep an eye on the fluid for a day or so and top up accordingly. For a complete drain and hydraulic winch install I used just under 2 litres of ATF.

I also changed the pipes that go between the PSP and PSB(power steering box). To do this I needed to lift the radiator up a bit to get the pipes over the front cross member.

(To admin please add this to the 80, 100 and 70 stickys)
 
Thanks for this - been waiting for you to post this prior to attempting mine.... :mrgreen:
If you don't mind me asking - what was the total cost / time involved??
 
Cost of the rebuild kit form Ian Rubie was in the region of £35 I think (will be more from your local dealer), I cant remember the exact cost as i ordered loads of other parts at the same time. Time wise if you have a vice handy, all the right tools and a helping hand for some of the bits (like holding the pipe wrench when undoing the drive gear) then it should take between 3-4 hours IMO.

BTW I forgot to add when putting the pump back onto the engine you may need to turn the crankshaft for the gears to mate, I think you will need a 32mm socket on the end of the crankshaft for that.

EDIT: you will need to add the cost of ATF fluid to that ;)
 
Started mine earlier today, had a few additional complications as I have a PTO winch which was blocking access from underneath...

Finally got the sodding thing out - but am struggling to remove the gear from the end of the shaft. 17mm double hex off no problem but can't shift the gear - before I get a little more brutal the woodruff key is definitely under the gear (and not on top) isn't it? I can't see it but don't want to cause any damage!

Assuming I'm correct - what is the best way of removing the gear without using a puller?
 
I left the woodruff key in place and used a wide concrete/stone chisel between the gear and pump. It needed a surprising large hit with a large hammer to get it off. Its not a method that I would recommend as you may end up bending the shaft or damaging the bearings, but if you understand the risk and are good at judging how much abuse the shaft can take then then you can try it. I got an experienced mechanic to do that bit.
 
if i could work out how to gix the variable speed solenoid in the steering box then i'd be happy!
 
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Thanks Rob, did mine today prior to putting the motor back in.

To remove the gear I popped down to my local garage and used their 3 legged puller :thumbup:

There seems to be one large 'o' ring in the kit that doesn't seem to fit anywhere... so it went in the 'bits left over' draw :D
 
Bat21 said:
There seems to be one large 'o' ring in the kit that doesn't seem to fit anywhere... so it went in the 'bits left over' draw :D
:? There were three large ones in my kit - and they were all used...
 
Justin_Elliott said:
Bat21 said:
There seems to be one large 'o' ring in the kit that doesn't seem to fit anywhere... so it went in the 'bits left over' draw :D
:? There were three large ones in my kit - and they were all used...
There were 3 in mine but I couldn't work out where one of them went?

The Blue one is for where the pump mates to the engine case, one of the Black ones goes between where the pump splits in half.... where did you manage to fit the 3rd one Justin?
 
pugwash said:
if i could work out how to gix the variable speed solenoid in the steering box then i'd be happy!

If they are the same as other Toyota one - easy

Remove the upper plastic parts (its all moulded on normally) I used a hammer & chisel to get all the stuff off. Then you'll find beneath an adjustable valve unit. Tweak away. I do this on the drift cars as they dont use the variable stuff.
 
Well after a leak from my pump for probably 4-5 years I thought I had better get it done and today ended up being D day.

My ATF was very brown and burned and stinky so I wanted to flush as much as I could out of the system and some varied colours came out, possibly water related! :icon-surprised: Anyway got it all apart and I have a couple of things to add.

Firstly the stator part that you were unable to remove is simply a ring, no more, and there is no other O ring underneath it. It just gets stuck in with the surface tension of the oil. A good bang on the bench had it out.

Secondly, the plunger in the unloader valve has a little ball valve within it with a tiny gauze in a hexagon on the end. There was all manor of toot in various places so I'm not sure if this gauze was blocked or not but it's clean now. I held the plunger in some rubber in the vice and was able to undo the end which has shims to set the pressure. Gave it a good clean and blow through with the air line.

image.jpeg image.jpeg image.jpeg

With the brown burned ATF I wondered what might have caused it and the usual culprit is heat (yes, really!). Heat gets into hydraulics by the oil being forced through a construction somewhere. This can be wear in the pump, an unloader letting by, that sort of thing. The heat then goes onto degrade pipework and seals, hence the leakage.
I'm not entirely convinced my leak was from the pump. The suction hose from the reservoir seemed to be weeping at its lower union with the inlet pipe to the pump, so I changed that for a piece of locally sourced fuel hose.

I have a cooler from a Jag that I might get around to fitting one day for the gearbox and the power steering.

A most useful thread Rob. Thank you.
 
Last edited:
Bob? Who's this Bob of whom you speak?

I have a kit to do mine and it probably needs it, but I also have a spare pump. Guess which option I'll be going with.
 
Bob? Who's this Bob of whom you speak?

I have a kit to do mine and it probably needs it, but I also have a spare pump. Guess which option I'll be going with.
I had a feeling it was wrong. Sorry ROB. :icon-biggrin:

Edited, that'll teach me to post while dinner's on the table!
 
On this theme, I've had two separate occasions where the flexi ATF pipe from the reservoir to the pump failed. Please don't ask for more details because on both occasions I had a mechanic get his hands cut and dirtied, not mine!

However, whilst ATF was pissing out to the stage that the pump no longer assisted the steering, I was still driving the vehicle.

Not a good thing to do, on 2 counts.

1. It's bloody heavy to steer an 80 with no PAS, after a few days I felt like Popeye-the-sailor man - on steroids - with cracked ribs!

2. As said in the OP, driving it with the system dry wears the pump.

After the fix, it all works well, but the PAS is noticeably less efficient than it used to be. It's good enough, but I came close to damaging the pump beyond use.

Running it dry is not recommended.
 
Some feedback after performing this refurb is in order.

Took the truck for about a 20 mile drive and from the word go the PAS is feeling transformed. It is so light but with good road feel and really easy to turn. It used to judder sometimes, rarely but it did, also it was far less easy to turn but nowhere near as bad as if it were Popeye (non PAS) steering. It's also quiet as a church mouse.

I've been having a think yesterday and today about this and I'm pretty sure the improved power and smoothness in the steering is down to the unloader (pressure relief valve) being nice and clean now, especially the miniature tea strainer gauze filter in the top of the plunger.

This also follows that if the unloader was not seating properly and was letting some of the fluid by then that would be the point where the system was generating heat. That heat was then responsible for wrecking the ATF, seals, O rings and most importantly the suction pipe from the reservoir to the pump.

So with this in mind Clive, it may be worth you checking the condition of your ATF power steering fluid. Give it a sniff, if it smells burned, it's happening for a reason. Might then be worth removing the unloader and cleaning out the strainer. Or at least having your man do it. :shifty:

It's early days but I suspect I may have solved what is causing heat in my PAS.
 
The ATF in my steering is as good as new Rich, well it was new 3 months ago and I'm checking it frequently so's not to have a repeat of last time. It's ruby red and smells like, well, ATF.

But on your advice, next service, which isn't so far away, I'll get them to check the unloader valve. I know they fitted a seal kit in the pump, but I can't be sure they stripped it down that far.

They do a good job in all fairness, so it's possible. They feelered the clearance on the pump vanes, that's how they discovered and reported the wear.

Still, it feels just fine to drive, there's no judder, it's silent and silky smooth.

The only difference is I need two fingers now to go from lock to lock when parked, instead of one, and I'm running 305s at that.

I'm well pleased, but I will mention it to them.

Thanks Rich, good advice. :thumbup:
 
Leaking power steering pumps seem to be quite common on the 80. This is not something you should ignore as the pump is gear driven of the crankshaft so if it were to seize due to a lack of oil it could cause serious damage to your engine. The fix is quite simple, all you need to get is a pump rebuild kit part number 04446-60070 for my 97 1HD-FT. This kit comes with all the internal oil seals, o-rings and copper crush washers for the high pressure pipe coming off it and a o-ring for the return pipe. As far as parts go all you need is in the kit. This guide is relevant to all 1H engines including 70 series and 100 series, but as I did this on an 80 it may be 80 specific in some cases.

You will need the following tools: socket set including an assortment of UJs and extensions, a 22mm socket (if you dont have one in your set) and a 17mm 12 sided socket (double hex). A vice is very useful.

The PSP (power steering pump) is located bottom left near the front of the engine. You have 3 access points, through the bonnet using extensions and UJs, through the front left wheel arch (remove plastic flap and turn wheel to the left or remove) and from the bottom (remove the front bash plate, the one near the steering damper).

You can either drain the fluid from the system completly or just disconnect the pipes and catch what comes out. It you wnat to drain it completely you need to disconect the return pipe that goes into the reservoir, see red arrow below.
PS%20resorvoir.bmp

When doing this be prepared to catch any fluid that comes out of the reservoir into a jar or something. Now take the return pipe and pull it out the bottom of the truck and place a container to collect the fluid underneath it. Now get someone to turn the engine on and turn the wheel lock to lock until there is no fluid coming out (best to do this with the vehicle on stands). You need to keep an eye on this as you could cause damage to the pump if you run it too long without fluid.

Once drained you need to disconnect the 2 pipes on the PSP. The one on the top needs a 22mm socket (high pressure) and the one underneath (return) is held in place with 2 bolts, 10mm socket. You will need to unbolt the return pipe from the bracket that holds it in place before removing it from the pump. This is the return pipe:
PS%20return%20pipe.jpg


Now you need to unbolt the pump from the engine. The pump is held in place by 2 bolts, use 14mm sockets (green below). I could only get to these using a spanner as there is not enough space for a socket. Also I have some weird foamy material in between the PSP and the fuel pump so access is difficult. Once you get the bolts out pull the pump out and you should have this in your hands:
15062010081.jpg


Now you can see you you need a 17mm double hex socket. Hold the gear with a pipe wrench (gear wrapped in rag) and unbolt the 17mm double hex nut. Now you need to pull the gear off which was rather difficult as the shaft is in the shape of a cone. Use a soft hammer or equivalent to break it free. Now split the pump by undoing the 3 bolts, 14mm sockets, taking note of how the 2 sides fit together (use match marks).

Now you will have 2 halves, one with the shaft and the other looking like this:
15062010075.jpg

There is one seal inside the half in the above picture but i had great difficulty taking all the bits out so i passed on that. According to the FSM you need to use a hammer (at the time i did not know where the 3rd large o ring went). If you do remove it take note of how the vanes go in, round edges near the outside. Remove the flow control valve, see red above and below

The other half will have a snap ring, just behind where the drive gear was. You will need to remove it in order to remove the shaft and bearing. Be careful not to damage the bearing. Once out the shaft should come out if you tap it with a hammer. You will now see the oil seal, prise it out with a screwdriver and take note of which way round it was. You should now have something like this:
15062010058.jpg


When assembling it you will need to coat all the internal parts with ATF fluid DII or DIII and the oil seal on the shaft needs a film or red rubber grease. If you managed to get the bits out that are below the vanes etc then you need to make sure it all aligns properly using the locating dowel. Once assembled put it back onto the engine and connect the pipes using new o-rings and crush washers. Do not overtighten the small bolts on the return pipe. Now connect the pipe that you disconnected from the reservoir and fill with ATF fluid (DII or DIII). To bleed the system turn the engine on for a few seconds and turn off then top up the fluid. Remember to keep turning the wheels from lock to lock when the engine is off. Once you don't need to keep topping it up let it run for a few minutes turning the wheels lock to lock to get all the air out of the system. When the fluid in the reservoir is clear (not foamy) then you know you got all the air out. Keep an eye on the fluid for a day or so and top up accordingly. For a complete drain and hydraulic winch install I used just under 2 litres of ATF.

I also changed the pipes that go between the PSP and PSB(power steering box). To do this I needed to lift the radiator up a bit to get the pipes over the front cross member.

(To admin please add this to the 80, 100 and 70 stickys)
 
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