this is rebuild on an SC400 ps pump. but this proceedure should work for most every model. the only speciality tools needed are a slide hammer, snap-ring pliers, and a press, but not absolutely neccisary, meaning you can get away with out using it, but it would be better if you could.

assuming that you know how to get the pump out put it on a vise

take off the 17mm pully nut and the pully. i actually loosened the nut on car while there was still belt tension

then take off the two 12mm bolts that hold on the oil feed (thats one of my favorite wrenches and its snap-on. one of 2 i own )

that is the high pressure oil feed to the rack. that is a 27mm bolt, inside there is a valve and a spring.

this is what is inside

on the other side of the pump there is a snap ring that has to be removed

temporarily install a 6 by 1.0mm bolt and pull the seat out with pliers

then take the snap ring off of the main shaft side

then take the four 14mm bolts out of the backplate and remove

dont loose the wave washer

the seal kit

i scavenged 2 nuts and welded them together then used a slide hammer to pull out the shaft. a nut and washer would work too

then i used an extension and tapped the pump rotor out with my hand but a hammer may be needed if more force is needed but a press is recommended here it it doesent come out by hand. and be sure to have your hand covering the back side to catch the rotor or else it will be a big mess

drive the shaft seal out with a screw driver and hammer

give it a good solvent bath and make it all clean, then dry it off with compressed air or air dry. i cleaned it agian with simple green because i feared that it might not be good if the o-rings touched the solvent or residue. then coat all of the inside up with ATF.

here is the pump rotor and housing. i found it good not to take it fully appart as it will be alot of mess with the rotor plates. there are 2 o-rings on each of the 2 side plates. i found that the o-rings were rock hard and i had to cut it with an xacto blade.

here is the o-ring i had to cut and you can kind of tell that it has become brittle over the years of heat cycling and ATF.

after washig the pump housing and coating of ATF inside place the new shaft seal in and use a 22mm socket to drive it in.


using a press (or a hammer) drive the shaft back in

replace snap-ring

replace seat o-ring

replace highpressure feed o-ring

replace oil feed o-ring

install seat

this is optional but measure the spring length minimum length is 36mm

install spring and valve and high pressure side bolt

install rotor housing making sure the shaft goes in to the rotor, and use a press (or a hammer) to push in the rotor housing. becareful not to damage the o-ring while pressing in the housing, and then install the wave washer in its grooves

install new o-ring in backplate. NOTE: the rebuild kit comes with instructions that say where 3 of the o-rings go. pay attention to that. theninstall back plate and torque to 29 ftlbs

install oil feed and torque to 9 ftlbs using the human torque wrench

torque high pressure side bolt to 51 ftlbs

install the pully and torque the nut to 32 ftlbs and you are done!!!

now all you have to do is slap that baby back in. i found that over the years of ATF contact and heat the hoses from the oil resovoir and to the rack have hardened and now is a good time to order them and changed them too along with the two hoses that come off of the idle up valve right off of the high pressure feed.

Great Stuff jzz30 and it's exactly what i was looking for with the part # as a bonus

thank you very much!
cheers! Blue

Beautiful pictures, but your tutorial is much too geekish for anyone except seasoned mechanic types like yourself - you take too many things for granted - like in step 1 you say "take off the 17mm pulley nut and the pulley." For crying out loud the pulley doesn't just fall off into ones hands, a puller is needed and just learning how to use a puller requires a tutorial in itself since pullers don't come with illustrated instructions.

Non mechanics like lexls do a much better job at making understandable tutorials for beginners. Sorry for the downer, but how else would you ever know your tutorial is not well suited for beginners? And probably 90% of the people on this forum are beginners.

Where are your tutorials?!?

Take it easy VGR. You're point is quite valid, those bolts are a royal PITA. But no puller is necessary, while the bolts resisted with vigor, my pulley literally did just fall into my hands when I pulled on it after releasing the serp belt. I would expect that pulley to just slide right off in most situations without need for a special puller. I consider myself a beginner and I just finished replacing my p/s pump and pressure hose, but I don't think a power steering pump rebuild job is one that a "beginner" would typcially attempt.

I guess I should have taken some photos, perhaps I'll document my adventures for others here soon. For now, I have to figure out why my water pump seems to have frozen up. I put a new serp belt on in the process and of the p/s pump replacement and when starting up after repair the new belt got hot and snapped because the pulley on the water pump wasn't moving. Any ideas???

Timing belt or serp belt? The serpentine belt doesn't touch the water pump.

You're correct, it has nothing to do with the water pump, as far as I can tell. That was just an initial assumption. It is the second idler pulley that the backside of the serp belt goes around.

To be more specific, it sits directly between the fan bracket and the fan clutch (I think), unless it is actually part of the fan clutch. But it's the pulley that's actually bolted to the fan bracket.

For a visual, check out http://www.lexls.com/timingbelt.html. Step 11 in that tutorial shows 4 bolts that hold the fan clutch on. Is the pulley that those four bolts go through part of the fan clutch?

Whatever the case may be, that pulley does not turn whatsoever. So I was thinking either bearings have broken down in there somewhere or the fan clutch has gone out on me. For what it's worth, I can spin the fan itself all day long with my hand.

Make sense?

I had it diagnosed at a Lexus dealer not long ago and was told about the p/s pump problem. In that diagnosis, there was mention of noise coming from the fan clutch, but that the bulk of the problem at that time was the p/s pump. Perhaps the fan clutch was more of a problem than the dealer led me to believe?

Thanks for any help on this, I'm stuck driving a borrowed Oldsmobile (when available) until I get this fixed!!!

That car looks very familiar...hey that's my car...haha. Anyways, go to step 33, once you remove the fan clutch it looks like that...it's the fan bracket.

You have the serpentine belt off and the fan clutch still doesn't spin? Replace the fan clutch...they seize up sometimes.

Okay, so I was able to find a fan clutch locally for only $50 so I'm planning to do that job today. But now that I have the new clutch in hand, I am beginning to think the problem may not be the clutch.

In reading your last reply, I noticed you question the spinning of the fan clutch and, actually, the cluth appears to spin as it should as I noted in a previous reply that I can spin the fan with my hand all day long. It's the pulley part of the fan bracket that does not rotate, even when I try to turn it with my hands. And yes, the serp belt is off.

Does that still sound like a clutch problem or is it something in the fan bracket that's crapped out?? I haven't seen a fan bracket part from any supplier, is the dealer the only source for that part? I'm about to take it all apart and get to the bottom of the problem, just reaching out for one last bit of advice before I do

Thanks again!!

Finally figured it out...it's the fan bracket mounting assembly for sure. I just went to the dealer and they had the part in stock and it was clear the problem is the bearings inside of it. They wanted $238 for it, so I'm looking around to see if I can get it cheaper before dropping that. Anyone know of a good place for that part? It's part #16307-50011.

As soon as I get that swapped out I should be good to go. Can't wait!!

Glad to see you found your problem. Try Taprecyling.com for a used bracket.

I checked out Tap, they have quite a stock of LS400s

This whip's been jacked up for a couple weeks now and I can't wait another one, so I just shelled out and got the part from the dealer. Swapped the parts out with very little trouble last night. I also kept my fan clutch and should be able to return the one I bought. Although a couple of those bolts almost had me giving up at one point, I finally got it all done. I didn't quite complete the job though. Today I'll flush the steering and coolant, put the battery back in, then go for a drive!!

hmmm....yea....like shaggz said the pulley did just fall right in to my hands...and i also noted that i used the serpentine belt tension to help with losening the nut.
seasoned mechanic??? i work on cars when needed, and im 20 going to college... i hope i didnt rub off as a veteran mechanic.

I rebuilt my son's P/S pump following the directions in this thread and it was great except that I have a noise in the pump kind of like you get when you turn the wheel all the way to the side and the steering is really stiff. Now I am going through trying to see if I did something wrong. My question is: On the high pressure oil feed (the picture with the caption "this is what is inside", do I understand correctly that the spring goes in first, then the piston (pointing toward the spring as shown) and then the 27mm bolt? I think we got it right but I needed to check.
Thanks for any help you can give.

Is it best to the the kit from Lexus? Could I use the AC Delco kit that other places offer?

Does anyone have a tutorial with pics on how to remove the p/s pump?