Catastrophic Power steering pump failure

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SKULLGRINDER

SKULLGRINDER

Joined
Jun 24, 2023
Threads
26
Messages
278
Location
Tucsonistan
Yesterday on my drive home I accelerated at an abrupt rate while “testing” out my newly installed o2 sensors. When I went to turn onto my street all of a sudden zero power steering assist. No noises whines or boom just nothing all of a sudden. With the engine at idle the fluid in PS res dos not move or circulate thus telling me the pump is no longer building pressure. Poor thing has seeped since I’ve owned the cruiser but I always kept it topped off and bled. Either way I have new hoses and rebuild kit on the way…. Just curious has anyone else experienced a complete pump failure like this before?
 
When my pump went out last summer, it threw fluid all over the engine compartment and made the failure known. When you look into the reservoir can you see the fluid moving or is there nothing? And no major leaks either? (I see you say it was weeping but nothing greater than the "norm")
 
Brindleboxer said:
When my pump went out last summer, it threw fluid all over the engine compartment and made the failure known. When you look into the reservoir can you see the fluid moving or is there nothing? And no major leaks either? (I see you say it was weeping but nothing greater than the "norm")
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No fluid movement. I have to rev up to 2-3k and it starts to move normally but at idle (950) it’s clear and staginent. Only other thing that I can think of is some sort of major blockage on the suction side from rapid acceleration although I feel like that would be rare
 
Ok, was going to suggest you loosen the pressure side at the pump and see if it was pushing fluid but it sounds as though it is not (deduced from there being no movement in the reservoir).

Has there been any work done to the truck in the last few months (other than the o2 sensor)? I only ask because I recall an issue a while ago with similar symptoms and it turned out to be the crank bolt not being torqued and therefore not driving the PS pump.

If you lift the truck and turn the wheel with the truck off does it move smoothly? Does it work the same with the truck running?
 
Brindleboxer said:
Ok, was going to suggest you loosen the pressure side at the pump and see if it was pushing fluid but it sounds as though it is not (deduced from there being no movement in the reservoir).

Has there been any work done to the truck in the last few months (other than the o2 sensor)? I only ask because I recall an issue a while ago with similar symptoms and it turned out to be the crank bolt not being torqued and therefore not driving the PS pump.

If you lift the truck and turn the wheel with the truck off does it move smoothly? Does it work the same with the truck running?
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Naw no recent work. Im going to further diag this evening when home. I’ll let you know what I find!
 
landtank said:
The vanes are bound up. Flush the system and start driving it. They usually free up. If they do flush the system again.
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I am afraid it’s too late

IMG_3136.webp
 
it was the vanes. the pump relies on centrifugal force to create pressure. It had pressure at the higher RPMs because there was higher centrifugal force than at idle.

Get a seal kit, clean everything up including the slots where the vanes go and put it back together. The vanes themselves have a rounded and flat end. The rounded end faces out toward the egg shaped bore.
 
landtank said:
it was the vanes. the pump relies on centrifugal force to create pressure. It had pressure at the higher RPMs because there was higher centrifugal force than at idle.

Get a seal kit, clean everything up including the slots where the vanes go and put it back together. The vanes themselves have a rounded and flat end. The rounded end faces out toward the egg shaped bore.
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Hoping dealership calls me today for seal kit. Opted for new HP and LP hoses as well. Why do a $20 flush when you could do a $400 system refresh :idea:
 
landtank said:
I bought this hose for my HiPressure hose


Perfect fit and used Japanese hose. Only issue is they put the protective sheathing on the wrong hose. And don't used the copper O rings that are supplied. I use the double ringed ones from belmetric in the 16mm size.
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I went with the rein branded high pressure hose as guys seemed to have good luck. Local hydraulic store for both hoses coming off the PS resi. PO had cut in some gotty in-line magnetic filter on the smaller of the two hoses. Happy to get rid of that. I’d imagine it’ll increase flow as well. My bearing is stamped HCH china… likely going to run down to grainger and grab a FKS bearing for piece of mind.

IMG_3139.webp
 
FWIW and future searches, AFAIK the original power steering "vane pump shaft" bearing (90363-17016) is/was a KOYO 6203Z (17x40x12 - shielded on one side, open on the other so the bearing is lubed/cooled by the PS fluid). Clearance is likely C3 (looser than C0 or C2) which allows for thermal expansion.

@SKULLGRINDER : How does the used shaft bearing feel, stiff, loose, grinding?? Generic parts store rebuilds are often sketchy, IME sometimes better to start over, either personally rebuilding a working original (not already rebuilt) pump, or pop for a new one.

FWIW
 
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Kernal said:
FWIW and future searches, AFAIK the original power steering "vane pump shaft" bearing (90363-17016) is/was a KOYO 6203Z (17x40x12 - shielded on one side, open on the other so the bearing is lubed/cooled by the PS fluid). Clearance is likely C3 (looser than C0 or C2) which allows for thermal expansion.

@SKULLGRINDER : How does the used shaft bearing feel, stiff, loose, grinding?? Rebuilds are often sketchy, IME sometimes better to start over, either
personally rebuilding a working original (not already rebuilt) pump, or pop for a new one.

FWIW
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Shaft is clean no hot spots or pitting. Bearing also feels good but will be replaced just due to that fact it’s a cheaper unit.
 
How much is a new pump? Are new pumps available?
 
The pump is still available and is around $350, part#44320-60182. I did mine last summer. I also replaced the hoses as one blew out and not knowing the condition of the others was piece of mind for me. IIRC the total was around $500 for everything.

The Toyota sales would definitely help the overall cost of this job, just on the pump and the HP hose would be worth the wait for a sale.
 
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SKULLGRINDER said:
I went with the rein branded high pressure hose as guys seemed to have good luck. Local hydraulic store for both hoses coming off the PS resi. PO had cut in some gotty in-line magnetic filter on the smaller of the two hoses. Happy to get rid of that. I’d imagine it’ll increase flow as well. My bearing is stamped HCH china… likely going to run down to grainger and grab a FKS bearing for piece of mind.

View attachment 4136266
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rein and CRP are the same company. thats what I'm using too its good.
 
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