So, it's not just the welds on the subframe that suck...

[Gofast]

My clutch engagement has been feeling a little funny for the past few weeks, but I chalked it up to clutch wear.
Then, today, I'm driving down the street and I feel something plop into the footwell...
It's the clutch stop, the two spot welds holding it on sheared clean off the firewall.



The car has held up to years of track and autocross like a champ, but I guess those thousands of furious clutch engagements finally took their toll.
So, here's my real question-
What's the over/under on JB-WELD'ing this thing back on?

I have a MIG that I'm good with, and my car is gutted, but space is limited and there's still a lot of crap in the footwell that I'd have to remove before I felt safe welding in there.
Additionally, the firewall looks to be internally sandwiched with asphalt sound deadening, which I'd rather not set on fire.

The clutch stop bracket is a solid 1.75 square inches of flat surface area, so I think I have a good shot at fixing this with epoxy...what say you?

[dcrothers]

What the hell. Give it a try. If it pops loose again you'll know you're in for the bigger job.

[thomas88162]

It's just a stopper; not like anything catastrophic can come from it falling back off. I'm not too familiar with JB weld, but I have heard that it doesn't respond to shock all too well. I think that epoxy would keep it where it is supposed to be, but it may eventually fail under shock as well. I bet a good silicon would work as long as it was properly cured.

[spacecowboy]

It's hard to tell without seeing the other side of the plate, but how about two Nutsert's & two small Allen bolts?

http://www.avdel-global.com/en/produ...-nutsertr.html

[Mark Bielick]

If you can reach the back side of the firewall, you could drill thru the spot welds on the flange, and remount the stop with machine screws. I would use stainless screws, and seal the holes with silicon. Use a large flat washer on the engine bay side of the firewall.

Mark

[Gofast]

If you can reach the back side of the firewall, you could drill thru the spot welds on the flange, and remount the stop with machine screws. I would use stainless screws, and seal the holes with silicon. Use a large flat washer on the engine bay side of the firewall.

Mark

Yeah, I've thought about that, or even re-designing the Clutch stop to be one big bolt, and just putting it through the firewall without the bracket.

[rf900rkw]

That looks to have failed from being hit repeatedly off-center. Rather than attaching to the floor at a single point, you may consider a steel strap say 3-ish inches long attached across the floor and the stop threaded through that.

You might also consider bronze pedal bushings to keep the pedal centered.

[328 Power 04]

Is there access from underneath? I'm not familiar with the exact location this falls at on the other side.

What I would do, if you're brave, is get a lot of wet rags, place them strategically around and weld like that in that small space. A small MIG might give you enough space. Since this isn't too structural, some tack welds would be enough, and wouldn't spray around too much. But of course this is just opinion, and it's what I'd attempt before JB Weld.

That looks to have failed from being hit repeatedly off-center. Rather than attaching to the floor at a single point, you may consider a steel strap say 3-ish inches long attached across the floor and the stop threaded through that.

You might also consider bronze pedal bushings to keep the pedal centered.

Are the Delrin ones adequate for this? Reason is that I bought a couple of sets from UUC a while back when they had a sale, and haven't installed them just yet.

[bplease]

Eesh I checked the bushings at Ireland engineering. $14? Sweet. Shipping to the middle of the US, $16.

[BladeRunner919]

Just wait for the 'Randy Forbes Clutch-Stop Reinforcement Kit'

[rf900rkw]

I've never tried the delrin in this application... can't comment on that. And the truth is it took 100K miles for the original bushings to fail, we don't have enough data on either set, yet.

But I like the bronze ones.

I get mine from Bimmerbum.com. Same price, don't know what he can do with the shipping.

[bplease]

Well crap, same price on shipping. Thank you for the link though. I guess I'll stick with the squeaky until I have a large enough order to justify the shipping.

[Randy Forbes]

Just wait for the 'Randy Forbes Clutch-Stop Reinforcement Kit'

I'd be crazy to develop something I had to lay in the footwell to install... :

I've had the Stygar Delrin bushes in my '99 for probably ten (>10) years now, and they're still keeping the pedal on-center and quiet. I bought two (2) sets at the same time (Stygar supplied them fitted to new pedals) and the other one is still in the box, waiting for the '01 (w/45k miles) to need it.

[328 Power 04]

Actually, looking at the UUC site, I found out that their bushings are made of UHMW, ultra-high-molecular-weight polyethylene, which is self lubricating and claimed as the highest impact strength, and high abrasion resistance. Enough big words to justify my purchase .

[spidertri]

AKG Motorsport sells the bushings too, they have bronze and delrin.

I just bought some parts from them and they refunded some of the shipping charge once they realized everything could fit in a small flat rate box.

[Gofast]

After looking closer and turning it over and over in my mental CAD simulator, I think I'm going to work towards a through-bolt solution, with some epoxy for added permanence.

The Clutch stop is an M10 bolt, so I should be able to get a long M10 and thread it through the bracket, through the firewall, and use a washer/nut on the backside. This all assumes I can get to the backside of the firewall in that spot, which I have yet to confirm.
I've had upgraded pedal bushings sitting on the shelf for almost as long as I've owned the car, but never installed them (it turns out the clutch squeak doesn't bother you in a gutted racecar).
Now I might install them just to keep the pedal alignment true.

[328 Power 04]

Going to any autoX, TMS, or MSR soon? I'd love to see what you did to your car.

[Vinci]

If you want to fix the pedal once and for all, just bite the bullet and get the Mason steel pedal.

I got one a couple years ago as a gift with some custom Delrin bushings, and it is easily the best thing that happened to the shifting in my car.

[dcrothers]

Ditto on the Mason pedal.

[Gofast]

If you want to fix the pedal once and for all, just bite the bullet and get the Mason steel pedal.

Ditto on the Mason pedal.

Anybody using the Mason pedal with a modified clutch/flywheel?
I'm running an M5 clutch and lightweight flywheel, which combined with a light car means the clutch bite is super short and direct as-is.
People who aren't me have trouble getting it cleanly off the line...
I'm mildly concerned that the higher-ratio pedal could make my car un-driveable.

[KeysCoupe]

Its a shame that the firewall side failed rather than the bracket side. That would have left two perfect holes to roset weld!
With what that bracket does, and the surface area evidenced by the lack of paint, I would use 3M Panel Bond #8115. This is an epoxy that has a bond strength usually higher than the tensile strength of the sheetmetal (in this case, the firewall).
-Donny

[Randy Forbes]

Its a shame that the firewall side failed rather than the bracket side. That would have left two perfect holes to roset weld!
With what that bracket does, and the surface area evidenced by the lack of paint, I would use 3M Panel Bond #8115. This is an epoxy that has a bond strength usually higher than the tensile strength of the sheetmetal (in this case, the firewall).
-Donny

I agree with Donny on this one; perfect application for an automotive grade panel adhesive, with only compressive loads__assuming you fit the new bushes to the pedal pivot, so it hits square on.

[CMM3]

I've been amazed by how well JB works,
I'd scuff up the metal to remove the paint and give the JB or the other panel bond stuff a try.
On my nephew's track beater it's held his floor together for years now - LOL

[Vintage42]

... I'm not too familiar with JB weld, but I have heard that it doesn't respond to shock all too well. I think that epoxy would keep it where it is supposed to be, but it may eventually fail under shock as well. I bet a good silicon would work as long as it was properly cured.

JB Weld is epoxy full of metallic particles, hardens to metal-like compound that can be sanded, drilled, tapped. Silicone is a better sealant than adhesive.
I think JB Weld, particularly with those two holes in the bulkhead to form a mechanical lock, would be a good choice.

[Pat Gautier]

I'm a huge fan of JB Weld. Used it for a lot of projects. Haven't used it for anything super-structural but it definitely holds well. Don't use the putty or the JB-Quick - they are more prone to failure. Rough up the metal to give it some tooth and leave the "weld" for a full day before putting any stress to it. Ideally you would keep it clamped but not an option in your application. Perhaps a stick wedged up against the stop to hold it in place or wedge some materials between the clutch pedal and the stop. You get the idea.