Update to Clutch/Throw bearing squeal

Good on ya, Bill, for letting everyone know what the fault was.  That's how we all learn.

I'd like to know how or why it happened with so few miles on new parts. Me thinks I may have one of those funky in between year (70-71) changes and had the wrong throw out bearing causing something funky... 

....or it just could be low quality parts, which I'm sure would be a surprise to most air cooled enthusiasts.

Do tell! Low quality parts!?!

From KEP:  All Kennedy Clutches are sold with an early style T/O bearing pressure ring. The ring is easily removed to make a late style pressure plate.  MADE IN USA.

 

 

 

Last year, the builder of my new engine - who does a lot of builds for drag racers - spec'd a Kennedy stage two clutch and solid disc for me. At the time, I was familiar with the Kennedy brand, but didn't know a 'stage two' from a stagecoach.

 

After the install, I was having clutch chatter problems, and my clutch pedal had turned into an elliptical workout machine. So, I decided to move down to a Kennedy stage one pressure plate and a 'softer' disc. We ended up installing a Kush Lock disc, and I've had no problems since.

 

The Kush Lock disc allows some 'give' on take up but does that without using springs.

 

A very wise air-cooled mechanic - who hangs out here sometimes - advised against the spring discs for exactly the reason you've discovered. Apparently, spring discs used to be OK back when car parts were made in places with names like Muncie, Sheboygan, and Ypsilanti. But now, springs that once knew their proper station in life are wont to drop out, stray from home, and wreak havoc in the neighborhood.

 

The neighborhood is changing. Be careful out there.

 

 

The snap ring snapped and bound up in the fingers. No noticeable damage but TB has a small bind. Can I reuse the pressure plate with a new ring and TB? Or is the pressure plate toast? Again less then 3K miles on all parts.

The stock pressure plate with a solid stock disc works good up to about 80hp. Then I use the Kennedy stage one and stock solid center ( no springs) disc up to 100hp. Next, suggest Kennedy stage two and stock solid center disc up to 150hp. Above 150hp, suggest Kennedy stage three and kush loc better solid center disc.  Never use the metal three or four puck disc as they are either ON or OFF and nothing in between. I tried these on several race cars and they caused all kinds of problems on the starting line and breakage.  I don't know what they are good for, but I never use them. 

 

The problem with the spring loaded stock disc or any spring loaded disc is they lack enough rivets to hold the center to the outsides of the disc and that is the weak link.  In a stock VW engine , they are great and smooth operating. 

 

If you don't see damage to the fingers on the pressure plate or they look all "even" to the eye, I would reuse it. Sometimes, things go wrong and do not cost an arm and a leg.

Going to convert it back to the way it was made, 3 Bolt collar over the input shaft and the late style throw bearing. My friend has the collar I'm looking for...

 

Thanks for all your help!

I'm going to disagree here. Kennedy Stage one pressure plate is good with my 180 hp. I'm using a stock 200 mm Sachs solid disc.

 

Why get a Stage 2 or 3 disc just to get a workout?

I would have not removed the better three bolt collar support. So, put it back on and use the Kennedy without the center part and all will match up and you have no worries about that center piece coming loose, as it will not be there. Problem solved.

The old Kennedy pressure plates, mostly sold by Berg Enterprises had a different pressure rating. When Kennedy came out with the "new" style , probably like you have, the rating dropped to 1700 psi on the stage one. If it works, leave your clutch set up alone. I believe the psi on the stage two is 2100 to 2300, depends on how old your Kennedy pressure plate design is and on the stage three 2300 to 2500, depending on design. I had to use the stage two with my 200 hp race engine with a Berg street/strip solid disc or I could hear the clutch slipping, not locking up, but ran slicks with aggressive launch.

 

My Kennedy stage two (with solid disc) had zero slip with a 100-120hp engine. And I mean zero. You couldn't make it slip if you tried, which is just what you want for the track.

 

But on the street, sometimes a little slip when you want it can be a good thing - like starting up a driveway ramp from a stop, or easing your way into a parking spot at 2 mph, or backing into the garage.

 

The quick snap take-up and pedal pressure of the stage two felt like it was really hard on stuff like the clutch cable and pedal (both notorious weak spots on our cars) and on bigger stuff too, like wheel bearings, transaxle, and even the engine itself. I mean, why punish this stuff every time you let the clutch out if you don't have to?

 

The stage one feels like a 'normal' clutch to me, both in pedal effort and in the rate of take-up.

 

 

Like lots of other things- the clutch set-up on a VW Type 1 wasn't really designed for 150- 200 hp. It's regrettably small, and no amount of "stage anything" can change that, so life becomes a bit of a compromise brought on by the nature of the beast. It's a bit like exhaust in that regard- there is no readily available ideal solution available on the commercial market. A dual disc set-up would be nice, but I doubt it would cost $200.

 

I've got a Stage 2 and an ACE/Blackline Copperhead disc (copper pucks on one side, composite on the other). It's aggressive on take-up- the hotter it gets, the better it feels. I've braced everything on the car to the point of absurdity, and have almost eliminated "juttering" in normal situations. Believe it or not, I can make it slip if I'm being nuts.

 

But I can't recommend this set-up for a normal street car. I've said it before, but after going a couple of bridges too far-- I think the perfect speedster set-up is about a 135- 150 hp 2110 (or similar). Such an engine would be perfectly happy with a Stage 1 and Kush-a-Lock. Good feel, nice take-up, enough holding power for the horsepower.

 

Perfect in it's simplicity.

Bill:

 

I had an "Early" clutch set-up on Pearl for about 14 years - early TO bearing, sleeve collar on the pressure plate diaphragm and a Kennedy Stage 1 running a non-spring disk.  I had slight clutch chatter from stop (only) especially when hotter out.

 

When I had the transaxle rebuilt, I got all the stuff to convert over to the later-style TO bearing (I bought the early-to-late bearing conversion from Rancho), installed the slider-sleeve on the case and removed the collar from the existing pressure plate diaphragm (not hard to do, but takes a fair amount of effort).

 

Clutch effort is identical (and was never all that hard to begin with, just nice) and the chatter is gone.  I also took my time putting everything in and adjusting it to a gnat's ass (especially the Bowden tube), rather than just throwing everything in in a semi-hurry as I often do.  I'm happy with the result.  gn

I guess you have not been around small block Chevy old engines ? The clutch set up is not much bigger, compared to the size on the VW. Actually, for a 98 Cu.In. engine, the clutch is more than big enough. That's 1594cc actual cc's.

On the exhaust systems, there is every size available from stock which is 1-1/8 inch ID or some are 1-1/4 ID, up to 2-1/4 inch ID. I don't know where you shop, but you will not find those exhaust systems advertised, because they have to be custom made, but many of the retailer who sell exhaust systems have shops doing the custom sizes. They are available, you have to ask and be willing to pay the price. For some reason, when you go from 1-5/8 inch up to 1-3/4inch, the price almost doubles. Ouch !!!

Well, different strokes for different folks I guess. I find this subject interesting. My Kennedy stage one setup came with a solid clutch disc and it was undriveable with the chatter. As an experiment, I put the vw sprung disc back in and the chatter went away but the disc wore out quickly from the extra hp I was applying to it. So, I had a local shop make me up a custom sprung disc with segmented Kevlar on one side and organic on the other.

 

Here are three pics showing the Kennedy solid disc which would not work and each side each side of the custom disc compared to the stock VW unit.

 

I have no way of knowing the HP of my engine but stock and new it should be 137 and I'm guessing with my setup I'm getting 115-120.

I'm lost. Are we talking about headers?

 

FWIW, a 180 mm VW clutch is just over 7" in diameter. I cut my teeth on old V8s (back in the day). SBCs are all 10.5"+. Most of the hipo stuff is 11". It doesn't sound like much, but that's actually quite a bit more surface area. 

200mm closer to 8 inches. The 228mm ones if you have a type four are about 9 inches. Again, talking here about 98 to 120 cu. in. 1600cc to 2000cc engines, not 300 plus cu. in or 5.0L size engines. By comparison the VW has plenty of clutch surface area. Who still uses the 180mm?? I never see any of my customers with that small clutch set up. Someone mentioned it was also hard to find large size and a variety of exhaust systems, so added that to my post.

 

Actually, there's another use for a stage two clutch - and, by chance, I just stumbled across it today.

 

It helped the doo-wop group, The Platters, record one of their signature songs - Only You. The song flopped when first recorded, but then, it was released a year later with a significant change they discovered while riding in a car that must have had a stage two clutch. That little change made it one of the most famous songs of all time.

 

Here's how Wikipedia explains it:

 

The Platters first recorded the song for Federal Records on May 20, 1954, but the recording was not released. In 1955, after moving to Mercury Records, the band re-recorded the song (on April 26) and it scored a major hit when it was released in May. In November that year, Federal Records released the original recording as a single (B-side - "You Made Me Cry") which sold poorly.  Platters bass singer Herb Reed later recalled how the group hit upon its successful version:

 

"We tried it so many times, and it was terrible. One time we were rehearsing in the car ... and the car jerked. Tony went 'O-oHHHH-nly you.' We laughed at first, but when he sang that song—that was the sign we had hit on something." According to Buck Ram, Tony Williams' voice "broke" in rehearsal, but they decided to keep this effect in the recording. This was the only Platter's recording on which songwriter and manager Ram played the piano.

 

And now you know the rr-rest of the story.

 

 

 

 

Friction is independent of surface area. Friction's only dependent on the materials' coefficients of friction and the clamping force. A larger surface area, however, does spread the heat out over a wider area. And since friction coefficients are dependent on temperature, you can play with the surface area to adjust the friction profile of the clutch. For example, a 4-puck with its small area will heat up more and faster than a full disk clutch of the same material and thus reach its peak friction sooner. This means it grabs faster than a full disk clutch.

 

The larger diameter clutch does provide more torque-holding capability because the force is applied, on average, at a greater distance from the center of the disk. Just as using a long breaker bar on a nut lets you apply more force than using a short wrench. Same reason larger diameter brake rotors provide greater stopping force.

Shifting gears a little bit, but staying on the subject of clutch parts, I was wondering if all the speedster owners, with the monster , high horsepower engines have added support to the middle of the clutch cable tube, which is found inside the tunnel ? Berg Enterprises used to put out their collection of "technical" articles. In that, they point out, with anything other than the stock clutch set up, with more PSI on an aftermarket pressure plate, the stock welded "tab" which the VW factory used will break. The break is caused by a slight bend in the clutch cable tube, inside the tunnel. Each time you press on the clutch pedal that cable tube tries to become straight and over years of use, with the high pressure plate, that point will snap off, inside the tunnel.

The recommended "fix" is to add new bracing at the point where the clutch cable tube bends. To do this requires some cutting into the tunnel for access to the bent spot, to attach some hardware to make that bent point stronger. Now, welding on the thin clutch cable tube is tricky, as the metal tube is not very thick. What I do, as my welding skills would burn a hole through the tubing is to install a small threaded U-shaped clamp, around the clutch tube, having drilled two small holes to match the OD on the U-clamp. You find these at any hardware store. They have light weight U-clamps but better to buy Cable clamps as the material is much stronger steel. So, with the two small holes, the bend in the clutch cable tube is now held good to the driver's side of the tunnel. Cut off any access past the two NUTS, which will be on the outside of the tunnel. Less exciting to use the threaded U-clamp and you will not burn down your speedster. This modification should be used with any pressure plate, other than the stock one. Not doing so, will certainly put stress on the other welded spots on the clutch cable tube. Those being by the pedal assembly, inside the tunnel, with two small spot welds from the VW factory to a cross over brace, inside the tunnel and last, better welds by the shift rod coupler area, under the back seat.

But , with any shorter and modified tunnel, as required on the speedster and/or 550, that clutch cable tube was made shorter and re-welded by the coupler area. But, that mid point, where the clutch cable tube bends, from the VW factory is not touched. I wonder if anyone doing these stock tunnel cutting and re-welding has done this modification to the clutch cable tube, inside the tunnel. So, you might want to consider this, as over time, more than likely, the small spot welds will break off at the mid-point of the clutch tube or at the welded area by the pedal assembly, all inside the tunnel. I know because I have done welding repairs on a flopping around clutch tube, many times. Given the chassis, if a modified VW floor pan is 40 plus years old, one really needs the clutch tube with more supports and/or clamp as described or added metal tab with new welding, where that bend is located.

If you hear some metal scrapping sound, coming from your tunnel, each time you press on the clutch pedal, with the engine OFF, that is the sound of a broken center weld, from the VW factory. Or, the spot welds by the pedal assembly, inside the tunnel have snapped or broken. Fix is to cut an access hole in the tunnel and use some professional welder to re-weld the tube to that factory front cross brace.

I added this little restraint which prevents the front end of the Bowden tube from pushing on the weld where everything enters the body. Seems to work.

That's a good idea, but the clutch cable tube still wants to be straight, so the moving and forces caused by the clutch cable, inside the tube, over 40 plus years of working will cause that small welded tab inside the tunnel to break.  If you ever had a chance to look closely at the welding VW did to hold the clutch cable tube inside the tunnel, it was engineered for only 1200psi pressure plate loads.  Amazing, their factory welds hold up as good as they do.  To repeat, I have seen many of the tubes come un-welded at both the center tab and second most place, at the area , inside the tunnel, by the pedal assembly. 

 

The question comes up about cutting access holes in the stock tunnel .  Does this weaken the car's chassis.  In the 2000 pound stock full bodied steel Beetle I have seen no problem caused by the access holes. In fact, I have seen some look like Swiss cheese , on race cars, where major sections of the tunnel were cut out to lighten up the vehicle.  I do not recommend but one four inch round hole on the passenger side close to that cross brace, which supports the clutch tube and one four inch round hole, a few inches back from the back end of the emergency brake.  If the emergency brake is still located in it's original location.  Front hole allows changing the clutch cable with no tools as you can slide the cable into the tunnel and hook it on the clutch pedal LEVER found inside the tunnel.  The middle hole in the tunnel is only to allow access to re-weld and/or add the suggested hardware clamp to hold the clutch tube to the driver's side of the tunnel.  Even if all the factory welds are good, that clutch tube is bending every time you press on the pedal.  Sooner or later, the welds will give out.  When the break, you have no clutch action, only noise inside the tunnel.  On custom made chassis with new tubes and new welds and I hope, more welds on the clutch tube, all this discussion should not apply. 

 

On sand rails, as I do not like the lack of feeling with hydraulic clutch parts, I use 3/8 inch diameter thick wall brake line, you can buy at any auto parts store.  That is welded in front, in the middle and at the transmission end, making for a stronger clutch cable tube insulation than what VW did at the factory.  If the only length they sell ( and this can be a fix for your badly worn out factory stock clutch tube) buy two pieces and use a union to join them, but drill out the inside of the middle of the union, to allow the cable to slide through. 

 

Changing VW's from semi-auto to manual, I have welded into the tunnel many of these creative engineered clutch tubes, as with the semi-auto chassis, there was no clutch tube.  I have yet to see any fail after years of daily use.  Try to find eight feet of quality 3/8 diameter mild steel round tubing and good luck on that.  All the metal sales places where I live, say they cannot get any, but they do have stainless steel.  Not easy to work with stainless steel, for welding into the tunnel, stainless to mild steel.  Not going to happen.  I know this might be a rare event, the clutch tube coming loose inside the tunnel, but just saying, with Stage Two and Stage Three, you really need to reinforce the clutch cable tube in your speedster.