Swapped master cylinder, but the linkage seems too short?

[DrieStone]

I swapped my master cylinder a few months ago, but due to other tasks, I didn't reconnect the pedal at the time. Tonight I attempted to reconnect the pedal to the linkage, but it seems too short. Even with the pedal at the floor, I couldn't line the hole in the linkage up. There is some adjustment left, but even if I maxed out the adjustment I'd still be really short.

I'll admit I tossed the old cylinder a while ago, but I did do a side by side comparison and didn't notice a significant difference.

I feel like I'm missing something here. I'm regretting tossing the old unit, because at least I could see if the connecting bits were different. I did try pulling on the linkage, but it doesn't seem to want to come any further back.

[Chillidoggy]

Brake, or clutch? You don't say which one. I would suggest you get in there with a camera, take some shots of the problem area,  and post them up here for the specialists.

 

[CarBuff]

Shouldn't have tossed the old cylinder.  I always fit the old adjusting arm to my new clutch cylinder (never needed to replace the brake master...JINX)

 

Another watchpoint is that there are TWO holes in the pedal arms, marked B or C. 🤪 Make sure you are aiming for the correct one...

[DrieStone]

This is the clutch. You can see in my pic that the pedal is all the way on the floor, I have maybe 4-5 exposed threads on the adjustment, but I would obviously need a lot more than that. There's no way that the linkage will mate up with the pedal.

I can press down on the linkage and it seems to have good feedback (and it bounces back), so I think the cylinder is functioning as designed.

I'm 90% that I adjusted the linkage to be the same distance out on the new assembly. It seems wild that I wouldn't have noticed that the fork is a good inch shorter (but it's possible).

I'd rather not do it, but my "B" plan would be to modify the fork (cut and weld) to make it work, but I fear that I'm just missing something here.

[DrieStone]

I took a good long look at things again today, and it looks like there's about 2 1/2 inches that I need to come up with. 

FYI. I bought the master cylinder form JAE in the US many years ago. It appeared to be a direct replacement. I'm scratching my head on this. I'm also pretty damn frustrated.

[drdoom]

It's been reported that one must retain the OEM pushrod when changing M/C's as the aftermarket can't cover all the variations in a practical manner. It's therefore quite possible you need to resolve a suitable pushrod. Sorry.

[DrieStone]

 

4 hours ago, drdoom said:

It's been reported that one must retain the OEM pushrod when changing M/C's as the aftermarket can't cover all the variations in a practical manner. It's therefore quite possible you need to resolve a suitable pushrod. Sorry.

I reached out to JAE, and they said as much. I didn't realize this, and I've discarded the original. I guess I'll be doing some fabrication!

[Chillidoggy]

Information about pedal heights is in the Lotus Service Notes.

[DrieStone]

My solve was to build an extension that fits over the existing linkage. I just finished it up tonight, and everything seems to work as expected. I'll need to test further, but I'm pretty happy with the result. I just don't like that it turned a 2 hour project into an 8 hour project.

[drdoom]

You'll be a lucky man if that 8 hour project is all the Esprit throws at you. Sublimely driving cars but not built to highest standard at every point, and whatever the DPO(s) may have futzed along the way might add to the challenges of owning. That said, you're in an enviable situation. Well done.

[DrieStone]

13 minutes ago, drdoom said:

You'll be a lucky man if that 8 hour project is all the Esprit throws at you. Sublimely driving cars but not built to highest standard at every point, and whatever the DPO(s) may have futzed along the way might add to the challenges of owning. That said, you're in an enviable situation. Well done.

There's a reason my car has sat in my garage for a good 15 years! Every time I work on it, I run into a roadblock. This time I'm not going to let it stop me. I know for a fact that as soon as I think I have everything sorted, it's going to throw more at me. 

I'm just disappointed in myself for discarding a part before I was 100% sure the problem had been fixed.

Now comes the arduous task of setting timing, synching carbs, tuning carbs. Even then, my plan is to just get it on the road, then find someone who can properly tune the car.

[drdoom]

Snagged my S2 in'97, still looking forward to my 1st turn at the wheel.