Does anyone know for certain if the roll pins in the bronze bushing kits are any good or not? I read some time ago that they were having quality problems.

Maybe more helpful would be if someone has a pic of the Porsche roll pin vs. the Weltmeister pin. Any obvious differences?

I heard the same about the welty roll pins breaking. I destroyed my factory one trying to get the bastard out, so I ended up using the Welt one, hasn't broken but I haven't driven that 914 much since I did it.

If I remember, the factory pin had more rolls in it than the Welt ones. I can't be sure that was a few years ago.

It's generally recommended that you throw away the Weltmeister roll pin in the kit and find a spiral one. I did so on Brad's and Rich Bontempi's suggestion. Can't compare the two for longevity cause I'm still in the middle of my restoration. But the original spiral type is considered the best. HPH should have them.

The difference is that the Weltmeister pin looks like an O looking at the end, and the original spiral one is like a @. (Don't have a pic).

The Welt pin I have is the rolled variety, it has 3 layers in the thickest spot.

I have a stock pin that I saved from my shift console on the transmission, I believe it is the same pin as is used in the pedal cluster. I also think the one I have is factory, and it looks very similar to the Welt pin. The only difference is that the factory pin might be made from a slightly heavier gauge metal? Hard to tell.

If the Welt pins were once made in a non spiral variety I am not surprised that they failed. If they have corrected this then I don't see any reason why we shouldn't use the Welt pins?

Hmmmm. The Weltmeister pin in my kit wasn't spiral. Maybe they've been improved. Not sure how they would stand up to the thicker factory ones.

i bought 3 factory pins recently, added them to a Stoddard order with a bunch of other small parts.

the pin in my bronze bushing kit (i couldn't tell you if it was a Weltmeister or not, got through PerfProds) was visibly indistinguishable and since i had spares on hand, used it as a test. that was 2 years ago - no issues.

i do believe that once upon a time, the kits came with substandard pins, but the word got back to the producers and they learned. (you can't have a whole lotta Porsche owners pissed at you for very long and not get the message...)

let's face it - the Porsche factory doesn't make the "factory" pins, they buy them from a hardware manufacturer. anybody can buy equivalent pins from the same suppliers...

Agreed Rich.

I will take a pic of the Welt pin when I get a chance. If someone has a factory pin on hand we can compare.

I think this is one of those things where a failure is corrected but not before it gets "urban legend" status. (like stainless steel brake lines et al.)

QUOTE (jkeyzer @ Aug 26 2005, 09:38 AM)

Agreed Rich. I will take a pic of the Welt pin when I get a chance. If someone has a factory pin on hand we can compare. I think this is one of those things where a failure is corrected but not before it gets "urban legend" status. (like stainless steel brake lines et al.)

Oops, I forgot to take pictures for you.. I rebuilt my pedal cluster with the weltmeister kit, and it was a "somewhat" old one that I picked up at dunkels 2.5 years ago. It was at the swap meet and was new in package, but not "new" (the guy I got it from had apparently bought it and not needed it, who knows how long ago). It came with a spiral roll pin, but it was made of significantly thinner metal than the original one. I reused my old one because of all the horror stories.

What we really need is to hear from people that have had them break, and whether or not they were spiral type.

I think they mythbusters should do the SS brake line myth.. that would be a fun one.

can the roll pin be substituted for some solid metal of the same size?

i could take some brass or aluminum and lathe it down

what size are we talking about?

QUOTE (bd1308 @ Aug 26 2005, 10:21 AM)

can the roll pin be substituted for some solid metal of the same size? i could take some brass or aluminum and lathe it down what size are we talking about?

We are talking about a pin about 3/16" diameter, that holds the clutch pedal to the rod that goes through the pedal cluster which has an arm on it that pulls the clutch pedal. The pin needs to withstand a few hundred pounds of shear force.. aluminum or brass isn't going to do it. A roll pin is nice as it holds itself in place, and the factory steel one does the job just fine. You could substutute a tight fitting piece of an appropriately sized drill bit, but then you would have to devise a way to hold it in place. Something like that may be necessary for some sort opf mega-clutch with insane pedal force, but not for anything near stock.

I installed the Weltmeister bushing kit a few years ago and used the roll pin that came with the kit. After 4000 miles It is still OK. It's just one of the things I'll be rechecking before the ride up to Portland next year.
Cheers, Elliot

QUOTE (jkeyzer @ Aug 26 2005, 12:38 PM)

I will take a pic of the Welt pin when I get a chance. If someone has a factory pin on hand we can compare.

i still have my stash of 3 factory (via Stoddard) pins; i'll scan them tonight...

Not sure which size but here is a link to the Spirol page

(I use them at work)

Spirol metric pins

M

QUOTE (Engman @ Aug 26 2005, 01:42 PM)

Not sure which size...

900.309.002.00 -- pin - S 6x28

says ETKA...

I just used a bolt and a nut. The clutch pedal was a press-fit on the shaft on my car, so the bolt is only there to ensure it doesn't spin on the shaft over time, or come off if it does loosen up. Has been working fine for several months now.

QUOTE (bondo @ Aug 26 2005, 11:27 AM)

QUOTE (bd1308 @ Aug 26 2005, 10:21 AM) can the roll pin be substituted for some solid metal of the same size? i could take some brass or aluminum and lathe it down what size are we talking about? We are talking about a pin about 3/16" diameter, that holds the clutch pedal to the rod that goes through the pedal cluster which has an arm on it that pulls the clutch pedal. The pin needs to withstand a few hundred pounds of shear force.. aluminum or brass isn't going to do it. A roll pin is nice as it holds itself in place, and the factory steel one does the job just fine. You could substutute a tight fitting piece of an appropriately sized drill bit, but then you would have to devise a way to hold it in place. Something like that may be necessary for some sort opf mega-clutch with insane pedal force, but not for anything near stock.

got ya....

so the OE ones work fine....until they snap, right?

About 15 years ago, when I rebuilt my pedal cluster with a Weltmeister kit and the roll pin supplied was just that a roll pin.

The pin did not last long. Luckily it broke in the parking lot at school. I was able to dig through some of the engineering labs and found a bolt that was close to the same size. The bolt, while close in size, was not an exact fit. The bolt lasted for the trip home but that was about it.

I replaced the failing bolt with a "coiled spring pin" as can be found in a good hardware store. These pins are like the name suggests, multiple wraps of the spring steel.

I don't know what comes with the newer Weltmeister kits, but I would check it to make sure that you are not stranded somewhere over a few cent part.



P.S.

did anyone else realize some of the pedal bushings are the same size as the headlight bushings and the bellcrank bushings for a 914-6 throttle?

I used the roll pin the came in my bushing kit from Pelican. Install about 9 months ago and driven steadily since and no problems.

I have "heard" of these problems as well, but not until I had installed the new roll pin. So, we'll see.

QUOTE (bd1308 @ Aug 26 2005, 01:53 PM)

so the OE ones work fine....until they snap, right?

you are having quite a run on obvious questions today, BD - Friday has come just in time...

*all of them* are fine until they snap.
the good ones are fine longer...

this pin is very highly stressed and it gets a LOT of repetitive stress. fatigue will overtake them all, eventually, even if they're somehow able to be kept non-rusty. (corrosion doesn't help fatigue resistance...)

the pin is in double-shear (good) but it still takes a lot of stress, which is why the triple-layer spiral is needed. in case of emergency you might use a 6mm bolt but since it cannot flex like a spiral pin, it will eventually transmit all the stress to the clutch actuating rod, which is fairly thin and just mild steel. a strong bolt (like 12,9) will be brittle and a ductile bolt (8,8) might not be strong enough. (bolts are rated for tensile, not shear, strength.) so eventually it'll wear a nice oval in the rod, or break, or both.

QUOTE (JOHNMAN @ Aug 26 2005, 01:58 PM)

did anyone else realize some of the pedal bushings are the same size as the headlight bushings and the bellcrank bushings for a 914-6 throttle?

Weltmeister has :-)

they package those bushings in pairs just for throttle bellcrank restoration. (911's use them too...)

yes, it's all my fault in phrasing....

Here's the stock roll pin. I couldn't find the weltmeister one I didn't use, but it looked just like this but the hole in the middle was about twice the size (because the metal was thinner). The number of layers was about the same.

this is a new pin as received from a dealer bought by the Porsche part number.

There's no problem with the new pins. If you're rebuilding your pedal assembly make sure you press the pin in from the top.

I have 12 cores here. 6 are now plated and 6 will get Zero-Rust for a factory look (all hardware replated). I did this thinking people might be interested in a lower price alternative or a "stock" look alternative. Am I right?

Zero-Rust is what the military uses to coat the bottom of Hum-Vees... billions of hours of salt testing etc. I use it now more than POR-15.

peeectures. we need peeeectures !

Broken camera... wifey dropped it!

Stock Look

QUOTE (jkeyzer @ Aug 25 2005, 10:39 PM)

Does anyone know for certain if the roll pins in the bronze bushing kits are any good or not? I read some time ago that they were having quality problems. Maybe more helpful would be if someone has a pic of the Porsche roll pin vs. the Weltmeister pin. Any obvious differences?

Per question : Use regular roll pins rather than a bronze pin. The Pcar engineers gave you consideration when they put the roll pin in that pedal. The pin is a shear pin. Shears when there is excessive force that could damage other parts in the train of mechanisms.
You can put whatever you want in there but you are creating a worse problem in the long run because if it doesn't shear as intended, an expensive part, the whole clutch pedal assembly is going to have a wobbled out hole. Then none of the roll pins mentioned work because they won't stay in the hole as intended. As far as using the new, more expensive pins mentioned, IMHO, you are just paying more money for something.

Who's talking about a bronze pin?

Alllllsssssssooo... I'm pretty damn certain it's not a shear pin.

Bronze pin, I assumed, included in a bronze repair kit meant that it was bronze. My error.

It's a shear pin if it is a roll pin. Neither of us will ever change it's intended purpose historically but as a retired lifelong industrial machinist who knows and experienced their intended purpose, I will stick with my experiences that roll pins are designed to shear under excess stress. Otherwise they would have used surface harden dial pins.

Won't argue with you since it's not that important to me but facts are facts. My 914 's will always have roll pins/shear pins/soft metal pins where the Pcar engineers put em.

Beyond that: It your 914. Use whatever you think is best suited for your dollar.

A roll pin is not a shear pin. It is designed to last, not to shear!

A shear pin is a specially designed pin, that has a built in weak point of specified strength, so that if the load on it is excessive, it will shear rather that cause the mechanism to find another weak point (IE if the load is excessive the weakest link in the "chain" will break first, and a shear pin is designed to be the weak link). A shear pin usually is a pin that is partially cut in half. In industrial equipment they are commonly used in mechanical drive mechanisms. This is done to keep the machinery from breaking (the shear pin will) in case of a jam. The shear pins are usually in a location with "easy" access, for ease of changing/replacing.

In a clutch mechanism on a 914/911, the cable itself is (in my opinion) is easier to change that the "roll pin" at the base end of the clutch pedal. And what possible reason is there to put a "shear" pin in a cable actuated clutch mechanism, ie what could bind up so bad that you would want to design in a shear pin to prevent something else from breaking?

Touche ... logical.... read like a page from a book.... BUT.... why is a roll pin in the clutch pedal assembly in all the 914's in the 1st place rather than anything more substantial, like a harden dial pin?

QUOTE (cooltimes @ Aug 27 2005, 12:48 PM)

why is a roll pin in the clutch pedal assembly in all the 914's in the 1st place rather than anything more substantial, like a harden dial pin?

my guess is that the roll pin can flex a little and absorb the constant shock loading. since it can flex a little, it keeps the hole in the mild steel clutch shaft from getting ovalled.

and, probably, it's easier to manufacture. it is designd to be removable. when you design plastic bushings into the pedal cluster, you are designing in a need for the cluster to be dismantled periodically for bushing replacement.

as long as the pin lasts longer than the bushings, it has done its job. more is not required.

Good explanation. I learned something new because of this thread.
I noodle off wrong sometimes but I always pay attention to those who probably know.

And, they are probably cheaper.

All of our cars, even Porsche's, don't forget, are at least 50% engineered by bean counters, and a penny saved on a thousand little pieces is another $10 profit at the end of the fiscal year.

Aren't you constantly amazed at how little parts on our beloved 914 came out of a vw parts bin, and are "cheap", ie window crank handles made out of cheap cast "pot" metal, and how much foam rubber you found in the window winder mechanism the first time you took one apart. If you did not find any, think about what all of that dried up dust was in the bottom of the door. Wonderful German engineering of anti-rattle design, stick in some foam rubber.

But, they do spline their shafts and do not use keys glued into sloppy fit keyways.

Here's the Weltmeister pin.

Definitely thinner metal, you can tell by the larger hole in the center.

Strong enough? I dunno. Definitely different and seems like thinner metal would make it weaker. I installed the cluster in the car with the Weltmeister pin, guess I'll see how long it lasts...

bondo, is this pin like the one you had that you opted not to use?

QUOTE (jkeyzer @ Aug 27 2005, 06:26 PM)

bondo, is this pin like the one you had that you opted not to use?

Yup, that's the one!

The Weltmeister pin WILL FAIL, mine did after 3,000 mile. The thin gauge of the pin starts to crack, then eventually splinters. You'll notice it when you start loosing clutch adjustment and the pedal does not come all the back.

QUOTE (motorphotog @ Aug 28 2005, 04:13 AM)

The Weltmeister pin WILL FAIL, mine did after 3,000 mile. The thin gauge of the pin starts to crack, then eventually splinters.

without having the two parts in hand to compare, to my eye, the dealer pin looks substantially identical to the pictured "Weltmeister" pin.

if we're getting the same part through dealer channels, perhaps we should be looking at alternate sourcing on the "good" pin. OTOH - there's thousands of 911's out there that specify exactly the same pedal arrangement, and this doesn't seem to be a big issue with them... perhaps there is less total drag without all the pulleys and such, but i have to believe the clutch forces for the bigger engines are greater. so i donno.

6500+ mi on my cluster rebuild...

I know that the hole through the "pedal" end and the hole through the "shaft" can wollow (spelling?) out and become elongated, because I have seen it. On one pedal cluster I drilled them out so they were round.

Roll pins are sold in all kinds of sizes, both english and metric. I do not have a metric drill set, but do have english in fractions and the numbered set (because I needed some once for some taps). Good fastner companies carry a wide selection of roll pins, and even ace hardware in the KC area has a large selection. The most expensive ones are made with spring steel.

If the roll pin fits tight enough that you have to drive it in, I do not think they will fail, but if you can push it in with your finger, then it is going to rock and flex everytime you engage and disengage the clutch, and eventually develop stress cracks. A loose pin will not only further distort the hole, but it will fail. So will a loose key in a sloppy keyway, therefore the reason in industrial machinery, that keys are held tight in a keyway with a lock bolt.

Is it possible that those of you who are having failures need to ream out the holes and use a larger pin in order to keep the pin from stressing due to "rocking back and forth" and stressing?

I suspect that both Porsche and Weltmeister just used the cheapest roll pins they could get their hands on at the time.

looks like jkeyzer needs to do a side by side pic of a weltmeister pin and a "current porsche" pin.

QUOTE (bondo @ Aug 28 2005, 07:59 AM)

looks like jkeyzer needs to do a side by side pic of a weltmeister pin and a "current porsche" pin.

That's basically what we just did, Rich posted a pic of his pin, and if you look at it closely, the metal is thicker than the one I posted. I will get a Porsche pin and show you both pins in the same photo if that's what it will take...

The roll pin that I had fail (Weltmeister kit from approx. 15 years ago) was a roll pin. (A single thickness of spring steel shaped into a coil).

The roll pin was almost one complete circle, not several wraps as shown in the photos posted in this thread. I would tend to believe that the vintage of the kits with problems was probably way back when my kit was put together (15 years ago), and the problem pins have been addressed.

I have no pictures of my failed pin as it failed some 15 years ago. The pin broke in 2 spots (at the stress concentration on either side of the shaft). I suspect that the bolt I used began to fail due to a sizing issue because it was not an interference fit.

The coiled pins are what the correct part should look like (as shown in the pictures in this thread). These high strength spring steel components are designed to slightly compress when installed (which is why the ends are slightly tapered). This profides for a very tight fit in the hole through the shaft and the clutch arm.

The holes in the shaft and in the clutch arm should be exactly the same size for the coiled pin to perform as intended (not allow any movement between the shaft and the clutch arm).


As far as I know this issue was addressed long ago.

If not, the coiled pins are available at better hardware stores, McMaster Carr, Porsche, or any number of other places.

Luckily, when one works well, you need not worry about it for years.



just my $0.02

Here is the photo of the Weltmeister pin that failed on me.

It broke in 3 places, both ends and the center portion staying in the long rod

i think what we've established in this thread is:

• All pins used in this application will eventually fail.
  
• Ovalled holes in the pedal and/or shaft will make matters worse/
  
• There -was- a batch of bad pins in the distribution chain a while ago.
  
• The current kit pins are substantially identical and appear to be working in service.
  
• The dealer pin is still available from the dealers and is cheap.
  
• The ultimate solution (what Porsche eventually did) is a hydraulic clutch, which is not cheap.
  

The only thing we're missing is whether the Weltmeister pins consistently have a shorter lifespan than the Porsche pins, despite the switch to a spirol design. The Porsche part is visibly made from heavier gauge steel so it may be stronger.

i agree, but i donno how to test that, zackly.

to an extent, the pins supplied with the bronze bushings are a victim of their own success. with the factory plastic bushings, they'd wear out, and you'd replace them - using a new pin. when the master cylinder seal failed, it'd flood the pedal cluster with brake fluid, and the bushings would swell, and you'd replace them - using a new pin.

now, the bronze bushings last long enough that the pin, not the bushings, are the wear/failure item.

side by side

As cheap as these roll pins are at your local hardware store, just do an annual on the replacement. Takes only a couple of minutes if you catch it before it breaks, shears, whatnot and needs replacing