Anybody got a write-up on a PS rack rebuild?
05-28-2009, 10:49 PM
#16
Former Vendor
The racks are way harder than the pumps....
I made a bunch of special tools to install all the seals, so that they go in straight.
Still takes me 6 hours or so to do one. The cleaning sucks up a bunch of time, all by itself. Then you need to decide what kind of uber lubricant is needed to keep the gears from "eating" themselves for lunch.
I made a bunch of special tools to install all the seals, so that they go in straight.
Still takes me 6 hours or so to do one. The cleaning sucks up a bunch of time, all by itself. Then you need to decide what kind of uber lubricant is needed to keep the gears from "eating" themselves for lunch.
05-28-2009, 11:19 PM
#17
Rennlist Member
The Rennbay seal kit is great, and generally their how-to is good, but beware of the advice on prying out the bottom seal in the "tower". If you screw that up you will have a permanent leak and an unusable (ie unexchangeable) rack. The best way to remove that seal is with a pilot (blind hole) bearing puller. HF has them for (IIRC) about 40 bucks. Makes life a lot easier.
05-29-2009, 02:29 PM
#18
Rennlist Member
I've put in new seals at the end of the rack several times. Sometimes it failed right away as it's hard to get the seal in well when you need to drive it backwards. I finally found that the rod was pitted way down the shaft where I didn't notice it. Only goes into the seal when near lock and I always remove the racks near center.
I've got the P/N for that seal somewhere and the one for the old-style PS pump, if anyone cares.
I've got the P/N for that seal somewhere and the one for the old-style PS pump, if anyone cares.
05-29-2009, 07:59 PM
#19
Nordschleife Master
Didn't use a kit. Just got a 20x42x7 double lip seal and put it on the front. The rack takes 26x35x7 and those are single lipped.
Like $4 a piece, although I had to get a few. If anyone's old-style pump (pre-83?) is leaking from the front, shoot me $5 plus shipping and one is yours.
Like $4 a piece, although I had to get a few. If anyone's old-style pump (pre-83?) is leaking from the front, shoot me $5 plus shipping and one is yours.
05-29-2009, 09:20 PM
#20
Rennlist Member
Hmmm... FWIW my front pump seal had the following info on the face:
ZF 0770 080 326
STEFA 18/CC/19.05x33.33x7.93/8.93 (near as I can make out from the full-resolution pics -- could have some of this wrong).
Anything ring a bell with what you have?
ZF 0770 080 326
STEFA 18/CC/19.05x33.33x7.93/8.93 (near as I can make out from the full-resolution pics -- could have some of this wrong).
Anything ring a bell with what you have?
05-29-2009, 10:07 PM
#21
Nordschleife Master
No, doesn't seem to match up. I ordered by that size and it's written on the seal. I think there were only two pumps offered on the 928. Call them early and late. The late one is aluminum and similar to the 944 pumps.
05-29-2009, 11:25 PM
#23
Former Vendor
I just found that Carl at 928 Motorsports has a steering rack rebuild kit, but I didn't find a write-up on how to do it.
Searches here didn't turn up much I could use. I think there were two or three that said they'd done it, but no pix or descriptions.
I found something on 928 Intls. site, but it doesn't have any pics and it basically says to replace all the o-rings and seals you find with new ones.
If anyone has done it or there's a write-up, I'd appreciate if you could point me in the right direction. The shark fund could sure use that extra few hundred if I don't have to pay for a rebuilt rack.
Thanks in advance for any help.
Searches here didn't turn up much I could use. I think there were two or three that said they'd done it, but no pix or descriptions.
I found something on 928 Intls. site, but it doesn't have any pics and it basically says to replace all the o-rings and seals you find with new ones.
If anyone has done it or there's a write-up, I'd appreciate if you could point me in the right direction. The shark fund could sure use that extra few hundred if I don't have to pay for a rebuilt rack.
Thanks in advance for any help.
05-30-2009, 01:24 AM
#24
Former Vendor
I just found that Carl at 928 Motorsports has a steering rack rebuild kit, but I didn't find a write-up on how to do it.
Searches here didn't turn up much I could use. I think there were two or three that said they'd done it, but no pix or descriptions.
I found something on 928 Intls. site, but it doesn't have any pics and it basically says to replace all the o-rings and seals you find with new ones.
If anyone has done it or there's a write-up, I'd appreciate if you could point me in the right direction. The shark fund could sure use that extra few hundred if I don't have to pay for a rebuilt rack.
Thanks in advance for any help.
Searches here didn't turn up much I could use. I think there were two or three that said they'd done it, but no pix or descriptions.
I found something on 928 Intls. site, but it doesn't have any pics and it basically says to replace all the o-rings and seals you find with new ones.
If anyone has done it or there's a write-up, I'd appreciate if you could point me in the right direction. The shark fund could sure use that extra few hundred if I don't have to pay for a rebuilt rack.
Thanks in advance for any help.
The only racks I rebuild are for the air bag cars, with the "clocking" issue and the "increased" power assist. I do these simply to make sure that the "increased" power assist can be retained....and I got sick of taking rebuilt racks back apart to correct the "clocking" problems.
The rebuilders (even Porsche's racks) don't seem to be able to understand that the flat on the input shaft needs to point in a certain direction, in order to be able to install them in the "airbag" cars.
The rebuilders also do not seem to understand that the racks with "increased" power assist have different pieces, than the racks without "increased" power assist.
05-30-2009, 06:28 AM
#25
Addict
Rennlist Member
Rennlist Member
Mike
Here is the steering rack rebuild write up I did about 2 years ago
https://rennlist.com/forums/928-foru...ings-pics.html
It's not really a write up of the process just trying to identify the many new seals and parts involved, but this is the daunting bit of the process. All there really is to it is being methodical, labelling which parts go where and in which order and above all cleanliness. THere aren't too many gotchas in there othere than remove old wiper seals with a blind bearing puller - don't pry them out with a screwdriver, you'll scratch the housing they fit in and will then leak, and use new crush rings on all the hard pipe connections. Other than that use fingers only and lube everything with Dextron 3 ATF as you reassemble.
Just remembered - despite ,missing piece 9, which I didn't actually need to replace, the kit I had probably has more replacement bits in it than you find in the easiy available kits in the US. Normally the Nylon wiper seal support washers and the semicircular friction pad for the pinion (PN 30.1) are not in the generally available kits.
Here is the steering rack rebuild write up I did about 2 years ago
https://rennlist.com/forums/928-foru...ings-pics.html
It's not really a write up of the process just trying to identify the many new seals and parts involved, but this is the daunting bit of the process. All there really is to it is being methodical, labelling which parts go where and in which order and above all cleanliness. THere aren't too many gotchas in there othere than remove old wiper seals with a blind bearing puller - don't pry them out with a screwdriver, you'll scratch the housing they fit in and will then leak, and use new crush rings on all the hard pipe connections. Other than that use fingers only and lube everything with Dextron 3 ATF as you reassemble.
Just remembered - despite ,missing piece 9, which I didn't actually need to replace, the kit I had probably has more replacement bits in it than you find in the easiy available kits in the US. Normally the Nylon wiper seal support washers and the semicircular friction pad for the pinion (PN 30.1) are not in the generally available kits.
05-30-2009, 08:55 AM
#26
Craic Head
Lifetime Rennlist
Member
Lifetime Rennlist
Member
Thread Starter
I did the rack rebuild over a year ago. This is an old thread that Heinrich just revived.
I took some pics but didn't do the write-up because I didn't know if I was doing it right. Sorry about that.Save yourself a whole bunch of grief and buy a rebuit rack from 928 International. For what they charge for a rebuilt rack, you simply can't go wrong. That's what I do.
The only racks I rebuild are for the air bag cars, with the "clocking" issue and the "increased" power assist. I do these simply to make sure that the "increased" power assist can be retained....and I got sick of taking rebuilt racks back apart to correct the "clocking" problems.
The rebuilders (even Porsche's racks) don't seem to be able to understand that the flat on the input shaft needs to point in a certain direction, in order to be able to install them in the "airbag" cars.
The rebuilders also do not seem to understand that the racks with "increased" power assist have different pieces, than the racks without "increased" power assist.
The only racks I rebuild are for the air bag cars, with the "clocking" issue and the "increased" power assist. I do these simply to make sure that the "increased" power assist can be retained....and I got sick of taking rebuilt racks back apart to correct the "clocking" problems.
The rebuilders (even Porsche's racks) don't seem to be able to understand that the flat on the input shaft needs to point in a certain direction, in order to be able to install them in the "airbag" cars.
The rebuilders also do not seem to understand that the racks with "increased" power assist have different pieces, than the racks without "increased" power assist.
All I did was clean everything up and replace whatever seals I could find in my kit.
Mike
Here is the steering rack rebuild write up I did about 2 years ago
https://rennlist.com/forums/928-foru...ings-pics.html
It's not really a write up of the process just trying to identify the many new seals and parts involved, but this is the daunting bit of the process. All there really is to it is being methodical, labelling which parts go where and in which order and above all cleanliness. THere aren't too many gotchas in there othere than remove old wiper seals with a blind bearing puller - don't pry them out with a screwdriver, you'll scratch the housing they fit in and will then leak, and use new crush rings on all the hard pipe connections. Other than that use fingers only and lube everything with Dextron 3 ATF as you reassemble.
Just remembered - despite ,missing piece 9, which I didn't actually need to replace, the kit I had probably has more replacement bits in it than you find in the easiy available kits in the US. Normally the Nylon wiper seal support washers and the semicircular friction pad for the pinion (PN 30.1) are not in
the generally available kits.
Here is the steering rack rebuild write up I did about 2 years ago
https://rennlist.com/forums/928-foru...ings-pics.html
It's not really a write up of the process just trying to identify the many new seals and parts involved, but this is the daunting bit of the process. All there really is to it is being methodical, labelling which parts go where and in which order and above all cleanliness. THere aren't too many gotchas in there othere than remove old wiper seals with a blind bearing puller - don't pry them out with a screwdriver, you'll scratch the housing they fit in and will then leak, and use new crush rings on all the hard pipe connections. Other than that use fingers only and lube everything with Dextron 3 ATF as you reassemble.
Just remembered - despite ,missing piece 9, which I didn't actually need to replace, the kit I had probably has more replacement bits in it than you find in the easiy available kits in the US. Normally the Nylon wiper seal support washers and the semicircular friction pad for the pinion (PN 30.1) are not in
the generally available kits.
05-30-2009, 02:08 PM
#28
Under the Lift
Lifetime Rennlist
Member
Lifetime Rennlist
Member
The rebuilders (even Porsche's racks) don't seem to be able to understand that the flat on the input shaft needs to point in a certain direction, in order to be able to install them in the "airbag" cars.
The rebuilders also do not seem to understand that the racks with "increased" power assist have different pieces, than the racks without "increased" power assist.
The rebuilders also do not seem to understand that the racks with "increased" power assist have different pieces, than the racks without "increased" power assist.
