So I was in the junkyard yesterday. I was looking at a passast in the 94-96 range. It was a standard with hydraulic clutch obviously....and It has a long skinny clutch slave. It is roughly 7" long and is probably 20-22mm in inside diameter.
Here is the cool part. It has a two whole mounting flange that is within maybe 2mm +/- of teh flange on the late model slave. It has a long rod....but that could be adjusted. The throw of the cylinder could be adjusted or spaced. It has teh most effective and perfect end seal/boot I have ever seen.
Here is the part # 357-721-261. Check it out. I will aquire the junk one for dissection this week and then inspect the throw length. Ray
Another possible clutch slave solution
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raygreenwood
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Wally
- Posts: 4564
- Joined: Mon Oct 28, 2002 12:01 am
Hey Ray,
I thought the Passat's had an annular (ring type) slave actuation??
Please make a picture of yours and post it. If its not possible, just pm/mail it to me. I am sure you still have my email
Tnx,
Walter
I thought the Passat's had an annular (ring type) slave actuation??
Please make a picture of yours and post it. If its not possible, just pm/mail it to me. I am sure you still have my email
Tnx,
Walter
T4T: 2,4ltr Type 4 Turbo engine, 10.58 1/4 mi in a streetlegal 1303
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
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raygreenwood
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- Joined: Wed Jan 22, 2003 12:01 am
Thats what I originally thought. Perhaps some years do. It appears that after 97...most of mysources do not list a slave or a master. They list pivot parts so most late ones must have gone back to the cable.
If you go to the site alloemcarparts.com and plug in the make VW, the year 96 you can see a picture of the exact part I have found.
Oddly...take a look at the picture of the master cylinder. It shows the reason why the slave can be so skinny. The master is fat....like on teh 412..
It got me to thinking...looking at the master cyl flange....if it fits.....why not plug the fluid tank port, modify the rod...and use the master as a slave?
The prices on that site are excellent. Ray
If you go to the site alloemcarparts.com and plug in the make VW, the year 96 you can see a picture of the exact part I have found.
Oddly...take a look at the picture of the master cylinder. It shows the reason why the slave can be so skinny. The master is fat....like on teh 412..
It got me to thinking...looking at the master cyl flange....if it fits.....why not plug the fluid tank port, modify the rod...and use the master as a slave?
The prices on that site are excellent. Ray
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Wally
- Posts: 4564
- Joined: Mon Oct 28, 2002 12:01 am
Yeah, I 've seen it.
Funny thng is, that if you type in 1989 as modelyear, no passat model is shown
Was the Passat model not imported in the US in earlier years?
Funny thng is, that if you type in 1989 as modelyear, no passat model is shown
Was the Passat model not imported in the US in earlier years?
T4T: 2,4ltr Type 4 Turbo engine, 10.58 1/4 mi in a streetlegal 1303
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
"Mine isn't turbo'd to make a slow engine fast, but to make a fast engine insane" - Chip Birks
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
I "think" that on this continent the Passat made its debut in either 90 or 91....except possibly for some gray market vehicles.
I did have a high school friend in 1981 who drove a 4 dr passat diesel....but that was the "dasher" chassis and her parents brought it from Germany.
There are lots of annular slaves that would bolt up to the type easily...but I have some issues with installing a slave that will potentially require dropping the transmission to change it in the middle of nowhere.
With the Passat slave that I found....there will be a couple of potential issues. (1) The stroke length is pretty long. I am betting that I could thread the outer end of the bore and install a long threaded "plug" as sort of an internal "stop" to limit the stroke. The rest could be adjusted by rod length.
(2) I'm not sure of its diameter looks to be about 22+mm....but it will require more pedal pressure to generate the same pressure as the stock 44mm type 4 slave.... if we use the stock type 4 master cylinder. That "might" be no problem, but I am betting that on the Passat, the push rod contacts the clutch release fork closer to where the release bearing is (farther from the pivot point).....wheras the type 4 pushrod contacts the release fork closer to the pivot point...requireing more leverage....and hence a larger diameter slave.
If I could find a replacement of slightly larger volume/dimater for teh type 4 master cylinder.....it might just even things out.
I could take a bus 22mm master cylinder....cut the end off, install a threaded plug (makig it a shorter single circuit cylinder) and one mounting ear and build a bracket for under the dash.
I have found a large amount of current larger volume clutch slave cylinders available that would suffice.....but the under dash mounting is still the issue at hand. Ray
I did have a high school friend in 1981 who drove a 4 dr passat diesel....but that was the "dasher" chassis and her parents brought it from Germany.
There are lots of annular slaves that would bolt up to the type easily...but I have some issues with installing a slave that will potentially require dropping the transmission to change it in the middle of nowhere.
With the Passat slave that I found....there will be a couple of potential issues. (1) The stroke length is pretty long. I am betting that I could thread the outer end of the bore and install a long threaded "plug" as sort of an internal "stop" to limit the stroke. The rest could be adjusted by rod length.
(2) I'm not sure of its diameter looks to be about 22+mm....but it will require more pedal pressure to generate the same pressure as the stock 44mm type 4 slave.... if we use the stock type 4 master cylinder. That "might" be no problem, but I am betting that on the Passat, the push rod contacts the clutch release fork closer to where the release bearing is (farther from the pivot point).....wheras the type 4 pushrod contacts the release fork closer to the pivot point...requireing more leverage....and hence a larger diameter slave.
If I could find a replacement of slightly larger volume/dimater for teh type 4 master cylinder.....it might just even things out.
I could take a bus 22mm master cylinder....cut the end off, install a threaded plug (makig it a shorter single circuit cylinder) and one mounting ear and build a bracket for under the dash.
I have found a large amount of current larger volume clutch slave cylinders available that would suffice.....but the under dash mounting is still the issue at hand. Ray
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
I "think" that on this continent the Passat made its debut in either 90 or 91....except possibly for some gray market vehicles.
I did have a high school friend in 1981 who drove a 4 dr passat diesel....but that was the "dasher" chassis and her parents brought it from Germany.
There are lots of annular slaves that would bolt up to the type easily...but I have some issues with installing a slave that will potentially require dropping the transmission to change it in the middle of nowhere.
With the Passat slave that I found....there will be a couple of potential issues. (1) The stroke length is pretty long. I am betting that I could thread the outer end of the bore and install a long threaded "plug" as sort of an internal "stop" to limit the stroke. The rest could be adjusted by rod length.
(2) I'm not sure of its diameter looks to be about 22+mm....but it will require more pedal pressure to generate the same pressure as the stock 44mm type 4 slave.... if we use the stock type 4 master cylinder. That "might" be no problem, but I am betting that on the Passat, the push rod contacts the clutch release fork closer to where the release bearing is (farther from the pivot point).....wheras the type 4 pushrod contacts the release fork closer to the pivot point...requireing more leverage....and hence a larger diameter slave.
If I could find a replacement of slightly larger volume/dimater for teh type 4 master cylinder.....it might just even things out.
I could take a bus 22mm master cylinder....cut the end off, install a threaded plug (makig it a shorter single circuit cylinder) and one mounting ear and build a bracket for under the dash.
I have found a large amount of current larger volume clutch slave cylinders available that would suffice.....but the under dash mounting is still the issue at hand. Ray
I did have a high school friend in 1981 who drove a 4 dr passat diesel....but that was the "dasher" chassis and her parents brought it from Germany.
There are lots of annular slaves that would bolt up to the type easily...but I have some issues with installing a slave that will potentially require dropping the transmission to change it in the middle of nowhere.
With the Passat slave that I found....there will be a couple of potential issues. (1) The stroke length is pretty long. I am betting that I could thread the outer end of the bore and install a long threaded "plug" as sort of an internal "stop" to limit the stroke. The rest could be adjusted by rod length.
(2) I'm not sure of its diameter looks to be about 22+mm....but it will require more pedal pressure to generate the same pressure as the stock 44mm type 4 slave.... if we use the stock type 4 master cylinder. That "might" be no problem, but I am betting that on the Passat, the push rod contacts the clutch release fork closer to where the release bearing is (farther from the pivot point).....wheras the type 4 pushrod contacts the release fork closer to the pivot point...requireing more leverage....and hence a larger diameter slave.
If I could find a replacement of slightly larger volume/dimater for teh type 4 master cylinder.....it might just even things out.
I could take a bus 22mm master cylinder....cut the end off, install a threaded plug (makig it a shorter single circuit cylinder) and one mounting ear and build a bracket for under the dash.
I have found a large amount of current larger volume clutch slave cylinders available that would suffice.....but the under dash mounting is still the issue at hand. Ray
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ubercrap
- Posts: 1394
- Joined: Sun Apr 18, 2004 8:00 pm
The vehicle you have always known as the Passat, was called the "Dasher", then the "Quantum" over here first, then, finally, the Passat name was applied with the 3rd generation (B3) platform.Wally wrote:Yeah, I 've seen it.
Funny thng is, that if you type in 1989 as modelyear, no passat model is shown
Was the Passat model not imported in the US in earlier years?
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bradey bunch
- Posts: 189
- Joined: Tue Aug 04, 2009 9:13 pm
Re: Another possible clutch slave solution
I need a slave cylinder for my car; I put on the 1980 vanagon master cylinder, and now the slave is leaking 
so I was wondering if anyone has actually tried any other slaves. It is the 44.5mm one.
so I was wondering if anyone has actually tried any other slaves. It is the 44.5mm one.-
raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
Re: Another possible clutch slave solution
The tough part is that its a very unique slave. I was actually just thinking about the slave problems this past weekend. The reason the 44mm slave has leaking problems is because it has several design flaws.
(1) The seal is far back on a rather long piston. There is no guidance for the long nose. During clutch actuation...the piston cocks slightly in the bore. It causes an odd wear pattern to both piston and seal. This would be very easily fixable by having a band about 2mm deep turned into the piston ahead of the seal groove within which it would be easy to install a teflon or UHMW wear strip or packing that keeps the piston centered in the bore and supports it so it cannot @@@@
(2) The piston skirt on the pressure side of the seal is the same diameter as the piston with no inlet vents. It makes for poor fluid flow with excessive pressure and poor lubrication of the seal. Its easily fixable by filing several small grooves across the skirt.
(3) The outer boot material sucks. I have one rock hard but pristine one that I could cast a silicone boot with. Or ...simply fashioning one out of sheet of high temp silicone and wiring it onto teh cylinder with thin stainless wire works well.
The real problem is getting seals. There is a place I know that can machine them out of the proper material for this. They made a couple of sets for me years ago. They were of the wrong material at the time (I didn't know it). They worked very well for about 30k miles then became too stiff because of the heat and fluid composition combined.
I think I asked this before but if any are interested in a group buy I could get one together. If I was buying one seal the cost woudl be roughly $200. If I were buying about 35 ...they would be about $5.71 each.
When rebuiling these slaves...one has to avoid the temptation to "hone" them. Honing should be only enough to remove rust specs. Then teh cylinder should be polished. Ray
(1) The seal is far back on a rather long piston. There is no guidance for the long nose. During clutch actuation...the piston cocks slightly in the bore. It causes an odd wear pattern to both piston and seal. This would be very easily fixable by having a band about 2mm deep turned into the piston ahead of the seal groove within which it would be easy to install a teflon or UHMW wear strip or packing that keeps the piston centered in the bore and supports it so it cannot @@@@
(2) The piston skirt on the pressure side of the seal is the same diameter as the piston with no inlet vents. It makes for poor fluid flow with excessive pressure and poor lubrication of the seal. Its easily fixable by filing several small grooves across the skirt.
(3) The outer boot material sucks. I have one rock hard but pristine one that I could cast a silicone boot with. Or ...simply fashioning one out of sheet of high temp silicone and wiring it onto teh cylinder with thin stainless wire works well.
The real problem is getting seals. There is a place I know that can machine them out of the proper material for this. They made a couple of sets for me years ago. They were of the wrong material at the time (I didn't know it). They worked very well for about 30k miles then became too stiff because of the heat and fluid composition combined.
I think I asked this before but if any are interested in a group buy I could get one together. If I was buying one seal the cost woudl be roughly $200. If I were buying about 35 ...they would be about $5.71 each.
When rebuiling these slaves...one has to avoid the temptation to "hone" them. Honing should be only enough to remove rust specs. Then teh cylinder should be polished. Ray
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albert
- Posts: 834
- Joined: Mon Mar 22, 2004 2:08 pm
Re: Another possible clutch slave solution
RAY,,if you look the part ,,251-721-263 A ,,this is a slave cylinder for the vanagon,, for to see the pict. ask to google pict. for that pn.. and google show you all the slave cylinder,, but this pn,, look like the 412 slave,,,albert
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
Re: Another possible clutch slave solution
Yes, techniclaly the vanagon slave would work. Because its a smaller diameter it would simply make the pedal pressure higher. But...it is also physically smaller and will not fit the bolt spacing of the 411/412. An adaptor plate could be made as well as a different rod.
This leads me back to the main argument: I can make kits for the 44.5mm slave that would be world class. The company I occasionally do work with can make the seal of ECOrubber 3 (an EPDM) that woldl just rock. But to really use teh new seal well and to keep the flaws in the piston from coming back...our pistons would need some light machine work. (a) a groove ahead of the seal for a packing (b) the rear skirt would have to be machined off...and then reattached with a center screw so the seal could be installed without stretching it to the breaking point...because machined seals woul have to be 85 durometer. In mnay ways they are better than molded seals. They are stiffer and have better profiles....but that stiffness means that stretching them over the end of the piston....considering that this piston has a very small center pin and very wide outside.....means that you will have problems. On the original seals I had made...bearing in mind that they were the wrong material.....I ripped 3 out of five seals installing them on the piston leaving me with an operating slave and one spare seal for my effort.
That being said.....an easier thing to do would be to build an external bracket similar to the vanagon...with an adjustable fulrcum/pivot point and then you could use the vanagon slave, Audi 5000 slave....or most any slave. Ray
This leads me back to the main argument: I can make kits for the 44.5mm slave that would be world class. The company I occasionally do work with can make the seal of ECOrubber 3 (an EPDM) that woldl just rock. But to really use teh new seal well and to keep the flaws in the piston from coming back...our pistons would need some light machine work. (a) a groove ahead of the seal for a packing (b) the rear skirt would have to be machined off...and then reattached with a center screw so the seal could be installed without stretching it to the breaking point...because machined seals woul have to be 85 durometer. In mnay ways they are better than molded seals. They are stiffer and have better profiles....but that stiffness means that stretching them over the end of the piston....considering that this piston has a very small center pin and very wide outside.....means that you will have problems. On the original seals I had made...bearing in mind that they were the wrong material.....I ripped 3 out of five seals installing them on the piston leaving me with an operating slave and one spare seal for my effort.
That being said.....an easier thing to do would be to build an external bracket similar to the vanagon...with an adjustable fulrcum/pivot point and then you could use the vanagon slave, Audi 5000 slave....or most any slave. Ray
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albert
- Posts: 834
- Joined: Mon Mar 22, 2004 2:08 pm
Re: Another possible clutch slave solution
RAY,, you can go on ,,google ,, and ask,,,www.yiparts.com,,there you can see all the slave 300 cluth slave,all the model ,with the dimention plus ,,the oil cc,,and ,,kw,,, for each cluth slave,,
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
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raygreenwood
- Posts: 11907
- Joined: Wed Jan 22, 2003 12:01 am
Re: Another possible clutch slave solution
There are some problems everyone needs to think about when trying to swap in a different slave cylinder. These are severe problems.
(1) The original 411 had a 22.25mm slave cylinder. The late 411 and 412 went to the 44.5mm slave cylinder.....withthe same master cylinder stroke and volume. With this design.....the 411 had a slave cylinder stroke exactly double The length of the stroke of the 412 with the 44.5mm slave.
(2) The problem this leads to is that if you go to a smaller diameter slave cylinder....which you will have to because 44.5mm is possibly the largest diameter auto slave I have ever seen.....then it will have to have a way to limit the stroke length. You cannot CHANGE the stroke length that is required of the clutch fork. If you shorten it....it will not disengage. If you lengthen it...it will damage both fork and pressure plate....been there and done that. This is set by where the pivot/fulcrum point for each particular clutch fork design is located.
(3) your only option in this case is to limit the master cylinder stroke by changing the pedal stop. This could get very bad very quick.
The best two options are to find a wat to suitably rebuild the stock 44.5mm slave cylinder....or install whatever cylinder you want externally with a variable fulcrum point so you can set the correct stroke length for any cylinder used. That actually has a lot of advantages. Ray
(1) The original 411 had a 22.25mm slave cylinder. The late 411 and 412 went to the 44.5mm slave cylinder.....withthe same master cylinder stroke and volume. With this design.....the 411 had a slave cylinder stroke exactly double The length of the stroke of the 412 with the 44.5mm slave.
(2) The problem this leads to is that if you go to a smaller diameter slave cylinder....which you will have to because 44.5mm is possibly the largest diameter auto slave I have ever seen.....then it will have to have a way to limit the stroke length. You cannot CHANGE the stroke length that is required of the clutch fork. If you shorten it....it will not disengage. If you lengthen it...it will damage both fork and pressure plate....been there and done that. This is set by where the pivot/fulcrum point for each particular clutch fork design is located.
(3) your only option in this case is to limit the master cylinder stroke by changing the pedal stop. This could get very bad very quick.
The best two options are to find a wat to suitably rebuild the stock 44.5mm slave cylinder....or install whatever cylinder you want externally with a variable fulcrum point so you can set the correct stroke length for any cylinder used. That actually has a lot of advantages. Ray
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albert
- Posts: 834
- Joined: Mon Mar 22, 2004 2:08 pm
Re: Another possible clutch slave solution
for who want the pn for the slave kit ,,411-798-041,,, in the kit we have the boots k4450 , the piston seal and the boots ring,,for the big piston,,albert