P.S. Seal Softner

[davidb]

Others may have had luck w/P.S. additives, not me. My mechanic
advised against my using any for my modest leaks. His take was
sure it'll soften the seals for awhile. It'll continue to soften the seals
until they practically dissolve [over time]. I took the gamble & tried
some awhile back. This morning my P.S. reseviour fluid, 100%, was
on my garage floor. Re-built rack time for yours truly. Ouch $$$$!
Just a caveat for Forum cruisers w/ZF P.S. systems. Leaks = new rack.

[len_newstrum]

Others may have had luck w/P.S. additives, not me. My mechanic
advised against my using any for my modest leaks. His take was
sure it'll soften the seals for awhile. It'll continue to soften the seals
until they practically dissolve [over time]. I took the gamble & tried
some awhile back. This morning my P.S. reseviour fluid, 100%, was
on my garage floor. Re-built rack time for yours truly. Ouch $$$$!
Just a caveat for Forum cruisers w/ZF P.S. systems. Leaks = new rack.The seal softener that I used--for really, really bad leakage--has worked great for the last couple of months. Will it last for years? Who knows.

The point is that for about $5 US you can put your car back on the road while you work the problem of getting a rebuilt rack on your shelf. Then, when you need it, you have it. It is cheap way of minimizing your down-time. To me, it was well worth trying.

BTW: I have big drip pans in my garage to contain any possible problems of leakage. They have 2X4 edges to withstand my wife occasionally driving over one. Of course, I've never done that.:rolleyes:

Just from a theoretical standpoint, I doubt that seal softeners will dissolve your seals. What they do is replace the plasticizer in the neoprene. Plasticizers are not solvents, so it simply returns the seal to as-new (chemically, not dimensionally: wear remains, but distortion--flat spots often the result of long periods of inactivity--are corrected).

After a few months it might be best to drain out the softener and refill the system with straight PS fluid. The softener has already done its job.

My mechanic, who only does Fiat/Lancia but chooses to not rebuild PS racks himself, recommended the use of PS seal sealant, based on his 35 years of experience with them. Obviously there is some disagreement among the "experts".

[Charley]

Others may have had luck w/P.S. additives, not me. My mechanic
advised against my using any for my modest leaks. His take was
sure it'll soften the seals for awhile. It'll continue to soften the seals
until they practically dissolve [over time]. I took the gamble & tried
some awhile back. This morning my P.S. reseviour fluid, 100%, was
on my garage floor. Re-built rack time for yours truly. Ouch $$$$!
Just a caveat for Forum cruisers w/ZF P.S. systems. Leaks = new rack.

David,
A while back I helped a buddy replace a ZF PS rack in his 1982 Zagato.He had rebuilt the rack twice before and wasn't sure what kind of PS fluid was used. There appeared to be ATF in the system. Will Holding recommended we use Pentosin CHF 7.1 Hydraulic Fluid (http://www.etyproducts.com/pentosin%20hydraulic%20fluids.htm) . I believe using ATF was the cause of his leaking racks.Apparently regular PS fluid and ATF is not as resistant to heat,pressure,and moisture as the green Pentosin fluid. As for using a PS stop leak or conditioning agent,all I can say is that I have used a product called QMI LiquiSeal with incredible success.

http://www.tampapad.com/resources/qmi_test.pdf
(see page 22)

This stuff would have been tried in my buddies leaky ZF rack,had he not already removed it.

[davidb]

I suspected I was postponing the inevitable Len. As you implied.
My "expert" is a semi-retired Porsche/Audi mechanic so he
should know about ZFs. He wasn't happy to hear of the rack's
total failure. His back is almost as bad as Jim Keller's. Ouch!
I'll look into that stuff Charley. Was using 100% synthetic
Valvoline P.S. fluid w/sealant additive. Haven't seen the stuff
for a long time on anybody's shelves. Hmmmm? All in all it's
a huge disappointment & expense I wished to avoid. After 3
yrs. of restore & a measly few weeks of driving, now this. It's
become a what next scenerio: throw a rod or bend a valve or
lose a gear or the clutch or . . . ?

[Charley]

Another thing that should be considered before installing the new rack is to flush the pump system.It is a bit messy but probably worth the effort to clean out the contaminants left by the old fluid.On my friends Zag we used regular power steering fluid to douche out the pump and lines.We filled the reservoir numerous times and started the engine to pump through the fluid,one guy gets the messy job of holding the high pressure line into a drain pan.Don't let the reservoir run dry though ! We went through about two quarts of power steering fluid. Don't forget to replace or clean the filter in the reservoir.

[davidb]

Yeah "don't run the pump dry". Kinda knew that but in order to
move it I gotta re-fill the reseviour which means fluid everywhere
again. My garage floor/driveway I can wash off. It's that crap spray-
ing all over the engine compt. AGAIN I hate. So where's this filter
located. As bad as this sucker is leaking, I'm pretty damn sure it's
flushed itself my friend. Thanks.

[Jim Keller]

Just fill it up with Lucas Oil brand Power Steering Stop Leak, it WILL work, you will then be able to continue to drive it the rest of the season and do the rack during the doiwn time of winter without drippping all over your garage floor or spraying all over the engine bay or more dangerously, the exhaust, setting fire to the car........that's actually a common occurrance on a Beta and has sent many to the grave over the years, I almost lost a 72 Cougar XR7 once and years later, an 82 T-bird to PS fluid fires when they ignited off the exhaust systems, headers on the Cougar and pipes in front of the cats on the T-Bird

If one bottle doesn't completely stop it, drain down the reservoirand re-fill with straight Lucas Stop Leak, I had to use two bottles on my 82 Zag, till I replaced the rack a year later, but it had a real bad leak, it ran out as fast as you poured PS fluid in, and the Lucas stuff, recomended by Kevin from the Lancia Consortium at tha time, really really does work! I was shocked!

[dimonVX]

Hello
I have replace the PS main power seal last week on my 79 HPE. It is no leaking now.
Thanks for idea, I have catch the codes on audi 100 ‘82 internet catalog.
The main seal is ZF 0770 196 053 The size 25x15x7
The bended rubber/steel gasket for tube ZF 7844 033 108
The replacement were easy, any qualified mechanic can do this.