[DeTomaso] Seals
jderyke at aol.com
jderyke at aol.com
Thu Jul 3 20:26:02 EDT 2014
Line pressures in hydraulic clutches are only about 300 psi max, so the compressibility of silicone fluid and the difficulty in bleeding the stuff don't matter so much. Even race engineer Carroll Smith says its OK in clutches under most circumstances. Brake systems with silicones are still NOT recommended, though. I'd be sure to tag any system carrying silicone fluid so the next mechanic is fully informed.
Contrary to what everyone thinks, silicone hydraulic fluids do NOT eliminate water in the lines. It gets in from simple displacement of fluid out of the master cyl. reservoir when you push the pedal, which sucks in moist air. The water condenses and settles to the lowest spot; it just doesn't dissolve in large quantities like it does in mineral based fluids. Back East I read of one guy who used it for quite a while in a classic car, and one winter the collected water froze in his low spot, plugging the brake line & leading to a crash!
-----Original Message-----
From: Stephen Nelson <steve at snclocks.com>
To: jderyke <jderyke at aol.com>; detomaso <detomaso at poca.com>
Sent: Thu, Jul 3, 2014 1:08 pm
Subject: Re: [DeTomaso] Seals
The thing I love most about this forum is the variety of folks that use
it. I am in the midst of honing the clutch slave cylinder; fortunately
it is not that bad.
Silicon brake fluid. Talk about an emotional issue. My poor '69 XKE
just doesn't know how bad it has it. I pulled rubbing alcohol through
the clutch and brake systems 35 years and 140,000 miles ago to clean
out the paint remover that was in it, pulling from the bleeds on the
calipers and the clutch slave. I then pulled a vacuum to clean out the
flushing alcohol, and filled with silicon fluid.
I've purged it every 5 years or so since. And, well, 35 years later
the brakes and clutch still work. Go figure.
I don't race my cars, I don't want to race my cars, and I don't want to
have the hassle of using a fluid designed to soften seals. I also
don't drive the Silver State events. Not sure what Silver State events
are, but I don't drive them.
Reminds me of a comparison some guy down in Dallas did 40 years ago -
showed that a nail rusted in silicon brake fluid and didn't in paint
remover. Go figure. Being a chemical engineer I sort of discounted
that demonstration.
Had this discussion many times over the years - always admire those who
want to go racing, but have to wonder if they ever think about those of
us grannies that just like to drive our cars. At less than 100 mph.
To my way of thinking silicon is good stuff if one is not panic
stopping often from high speeds.
Stephen Nelson
[1]SNClocks.com
Click here to join one of our mailing lists [2]Contact Lists
Click here for our new [3]Hammered Dulcimers galleries
Click here for [4]my new blog on finding happiness in retirement
_______________________________________________________________________
From: jderyke at aol.com [mailto:jderyke at aol.com]
Sent: Thursday, July 03, 2014 12:23 PM
To: steve at snclocks.com; detomaso at poca.com
Subject: Re: [DeTomaso] Seals
Two problems with stock clutch slave cylinders. First, they are made of
some sort of pre-rusted iron. Pits form immediately even in the box.
Second, when you hone out the pits that tear up seals, the resulting
bore is often either too oversized for new replacement seals to fit, or
the honed bore becomes cone-shaped front-to-back. So the repair usually
leaks within a week. And since the clutch hydraulics wear out as a
system, fixing the slave often causes a matching master to begin
leaking.
The REAL Fix is to find a slave (or master) that does not instantly
corrode: hard-anodized aluminum or a steel or brass liner pressed in a
stocker. This has been a problem since the Pantera was still in
production. All the above 'fixes' applies to clutch masters too. Some
originality-freaks use silicone fluid in non-leaking clutches only.
Clutch pressures are low enough so the stuff works half-way-decently on
the street, unlike in brakes. But I wouldn't drive Silver State events
with silicone fluids anywhere in my car.
-----Original Message-----
From: Stephen Nelson <steve at snclocks.com>
To: detomaso <detomaso at poca.com>
Sent: Thu, Jul 3, 2014 11:22 am
Subject: [DeTomaso] Seals
Got to the point I needed seals for the clutch slave cylinder on 5332.
Talked to Dennis at my favorite supplier - Panty Perf - he doesn't
carry. So, tried a couple of seal outfits here in Portland. Unanimous
opinion - people don't carry seals any more, but one shop did manage to
find a 1 inch piston that would go in, and all I would have to do is
turn a different cup on the end that the rod goes into.
So, being from OKC - I called Sealco in OKC.
[1][5]http://www.sealcompany.com/ God bless Sealco. I used to live in
OKC - needed any kind of seal they had it. And yup, like $3.30 each -
no problem.
Youse guys need seals - Call Sealco!
Stephen Nelson
References
1. [6]http://www.sealcompany.com/
_______________________________________________
Detomaso Forum Managed by POCA
DeTomaso mailing list
[7]DeTomaso at poca.com
[8]http://poca.com/mailman/listinfo/detomaso_poca.com
References
1. http://www.snclocks.com/
2. http://fs19.formsite.com/kagforms/form675003155/index.html
3. http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/About-Steves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
4. http://www.perfectoldman.com/
5. http://www.sealcompany.com/
6. http://www.sealcompany.com/
7. mailto:DeTomaso at poca.com
8. http://poca.com/mailman/listinfo/detomaso_poca.com
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DeTomaso mailing list
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http://poca.com/mailman/listinfo/detomaso_poca.com
-------------- next part --------------
Line pressures in hydraulic clutches are only about 300 psi max, so the
compressibility of silicone fluid and the difficulty in bleeding the
stuff don't matter so much. Even race engineer Carroll Smith says its
OK in clutches under most circumstances. Brake systems with silicones
are still NOT recommended, though. I'd be sure to tag any system
carrying silicone fluid so the next mechanic is fully informed.
Contrary to what everyone thinks, silicone hydraulic fluids do NOT
eliminate water in the lines. It gets in from simple displacement of
fluid out of the master cyl. reservoir when you push the pedal, which
sucks in moist air. The water condenses and settles to the lowest spot;
it just doesn't dissolve in large quantities like it does in mineral
based fluids. Back East I read of one guy who used it for quite a while
in a classic car, and one winter the collected water froze in his low
spot, plugging the brake line & leading to a crash!
-----Original Message-----
From: Stephen Nelson <steve at snclocks.com>
To: jderyke <jderyke at aol.com>; detomaso <detomaso at poca.com>
Sent: Thu, Jul 3, 2014 1:08 pm
Subject: Re: [DeTomaso] Seals
The thing I love most about this forum is the variety of folks that use
it. I am in the midst of honing the clutch slave cylinder; fortunately
it is not that bad.
Silicon brake fluid. Talk about an emotional issue. My poor '69 XKE
just doesn't know how bad it has it. I pulled rubbing alcohol through
the clutch and brake systems 35 years and 140,000 miles ago to clean
out the paint remover that was in it, pulling from the bleeds on the
calipers and the clutch slave. I then pulled a vacuum to clean out the
flushing alcohol, and filled with silicon fluid.
I've purged it every 5 years or so since. And, well, 35 years later
the brakes and clutch still work. Go figure.
I don't race my cars, I don't want to race my cars, and I don't want to
have the hassle of using a fluid designed to soften seals. I also
don't drive the Silver State events. Not sure what Silver State events
are, but I don't drive them.
Reminds me of a comparison some guy down in Dallas did 40 years ago -
showed that a nail rusted in silicon brake fluid and didn't in paint
remover. Go figure. Being a chemical engineer I sort of discounted
that demonstration.
Had this discussion many times over the years - always admire those who
want to go racing, but have to wonder if they ever think about those of
us grannies that just like to drive our cars. At less than 100 mph.
To my way of thinking silicon is good stuff if one is not panic
stopping often from high speeds.
Stephen Nelson
[1]SNClocks.com
Click here to join one of our mailing lists [2]Contact Lists
Click here for our new [3]Hammered Dulcimers galleries
Click here for [4]my new blog on finding happiness in retirement
_______________________________________________________________________
From: [1]jderyke at aol.com [[2]mailto:jderyke at aol.com]
Sent: Thursday, July 03, 2014 12:23 PM
To: [3]steve at snclocks.com; [4]detomaso at poca.com
Subject: Re: [DeTomaso] Seals
Two problems with stock clutch slave cylinders. First, they are made of
some sort of pre-rusted iron. Pits form immediately even in the box.
Second, when you hone out the pits that tear up seals, the resulting
bore is often either too oversized for new replacement seals to fit, or
the honed bore becomes cone-shaped front-to-back. So the repair usually
leaks within a week. And since the clutch hydraulics wear out as a
system, fixing the slave often causes a matching master to begin
leaking.
The REAL Fix is to find a slave (or master) that does not instantly
corrode: hard-anodized aluminum or a steel or brass liner pressed in a
stocker. This has been a problem since the Pantera was still in
production. All the above 'fixes' applies to clutch masters too. Some
originality-freaks use silicone fluid in non-leaking clutches only.
Clutch pressures are low enough so the stuff works half-way-decently on
the street, unlike in brakes. But I wouldn't drive Silver State events
with silicone fluids anywhere in my car.
-----Original Message-----
From: Stephen Nelson <[5]steve at snclocks.com>
To: detomaso <[6]detomaso at poca.com>
Sent: Thu, Jul 3, 2014 11:22 am
Subject: [DeTomaso] Seals
Got to the point I needed seals for the clutch slave cylinder on 5332.
Talked to Dennis at my favorite supplier - Panty Perf - he doesn't
carry. So, tried a couple of seal outfits here in Portland. Unanimous
opinion - people don't carry seals any more, but one shop did manage to
find a 1 inch piston that would go in, and all I would have to do is
turn a different cup on the end that the rod goes into.
So, being from OKC - I called Sealco in OKC.
[1][5][7]http://www.sealcompany.com/ God bless Sealco. I used to live in
OKC - needed any kind of seal they had it. And yup, like $3.30 each -
no problem.
Youse guys need seals - Call Sealco!
Stephen Nelson
References
1. [6][8]http://www.sealcompany.com/
_______________________________________________
Detomaso Forum Managed by POCA
DeTomaso mailing list
[7][9]DeTomaso at poca.com
[8][10]http://poca.com/mailman/listinfo/detomaso_poca.com
References
1. [11]http://www.snclocks.com/
2. [12]http://fs19.formsite.com/kagforms/form675003155/index.html
3. [13]http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/About-Ste
ves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
4. [14]http://www.perfectoldman.com/
5. [15]http://www.sealcompany.com/
6. [16]http://www.sealcompany.com/
7. [17]mailto:DeTomaso at poca.com
8. [18]http://poca.com/mailman/listinfo/detomaso_poca.com
_______________________________________________
Detomaso Forum Managed by POCA
DeTomaso mailing list
[19]DeTomaso at poca.com
[20]http://poca.com/mailman/listinfo/detomaso_poca.com
References
1. mailto:jderyke at aol.com
2. mailto:jderyke at aol.com?
3. mailto:steve at snclocks.com
4. mailto:detomaso at poca.com
5. mailto:steve at snclocks.com
6. mailto:detomaso at poca.com
7. http://www.sealcompany.com/
8. http://www.sealcompany.com/
9. mailto:DeTomaso at poca.com
10. http://poca.com/mailman/listinfo/detomaso_poca.com
11. http://www.snclocks.com/
12. http://fs19.formsite.com/kagforms/form675003155/index.html
13. http://www.snclocks.com/TheRestofourWorld/Hammered-Dulcimers/About-Steves-Dulcimers/19824807_4sHGgj#1558377542_LKmkrT7
14. http://www.perfectoldman.com/
15. http://www.sealcompany.com/
16. http://www.sealcompany.com/
17. mailto:DeTomaso at poca.com?
18. http://poca.com/mailman/listinfo/detomaso_poca.com
19. mailto:DeTomaso at poca.com
20. http://poca.com/mailman/listinfo/detomaso_poca.com
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