Shift coupler adjustment question--post-Wevo

[mbintx]

I installed a Wevo shift coupler last week. Buttoned it down and rowed through the gears in the garage and during a neighborhood test drive. All gears engaged perfectly, and I felt quite pleased with myself.
Fast forward a few days and I was cruising down the highway when I needed to downshift from 5th to 4th. Apparently 4th gear is not where it used to be, and it needs a more deliberate pull back and to the left than before. This makes me a bit nervous, as I don't want to accidentally find 2nd instead of 4th.

Since all other up- and downshifts are fine, I'm wondering how to adjust the shift coupler to alleviate this issue. It's a 915 box.

[DRACO A5OG]

How do the shifter bushings look?

[mickey356]

I had to do some coupler tweeking on my 915 when I put a rennshift in my SC. I recall driving around with a couple 10mm wrenches (I think they were 10mm) and pulling over to do slight adjustments. Not sure where I found the info on which direction correlated with which adjustment but I wanna say they came with the shifter. I just remember a little did a lot. Sorry for not being more specific. I'll do a search and see if I can find it.
I put a rennshift in my 912 and haven't had any issues with up or down shifting.

[mickey356]

Maybe this will help?
Porsche 911 WEVO Shifter Installation | 911 (1965-89) - 930 Turbo (1975-89) | Pelican Parts DIY Maintenance Article

[Bill Verburg]

besides bushes the stock clap goes bad w/ age,

symptom: the shifter goes out of adjustament after a few shifts solution a Wevo clamp

[emac]

I don't have a Wevo but after changing ALL the bushings including the shift rod bushing I can say it's never been better --and Oh. Don't do the fifth to second at high speed. Ask me how I know. $$$$$
Ernie

[mbintx]

Originally Posted by DRACO A5OG

How do the shifter bushings look?

Bushings are fine. Just trying to find out in what plane I need to adjust the shift linkage to get 4th gear back to where it was without affecting all other gear locations. It's just odd that only the 5 --> 4 shift was negatively impacted by the coupler install...

[universeman]

I have a WEVO PSJ in my car. I adjusted it the same way as the stock coupler and it's fine. The coupler shouldn't affect the distance between the gears at all, that's done in the shifter and transmission -- the coupler should just set the relative (front-back, left-right) placement of the gear pattern. Your issue could be in your shifter. You might look at a Rennshift or a rebuilt shifter box.

[mbintx]

Originally Posted by universeman

I have a WEVO PSJ in my car. I adjusted it the same way as the stock coupler and it's fine. The coupler shouldn't affect the distance between the gears at all, that's done in the shifter and transmission -- the coupler should just set the relative (front-back, left-right) placement of the gear pattern. Your issue could be in your shifter. You might look at a Rennshift or a rebuilt shifter box.

I guess I'm not being clear. When I removed the stock coupler and replaced it with the Wevo, I marked the relative position of the shift linkage so that it would be back in its original place and orientation when I tightened everything down. I then ran through all the gears in my garage and everything felt right. It wasn't until I got on the highway that I discovered that the 5-4 shift no longer slides in properly.
I could loosen the Wevo and try to rotate the shift linkage a bit on its axis, but since third gear is working fine (both up- and downshifting) I'm reluctant to move it. (I'm assuming 3rd and 4th are on the same plane.)

[universeman]

I think what you're saying makes sense. What I'm saying is that the double-H pattern of shifting is not shaped by the coupler, it's shaped by the transmission and the shifter working together. So if the double-H pattern isn't 'clean' like yours is not clean, the problem is not likely to be the coupler.

The coupler "positions" the double-H, moving it left-right-fwd-back, but does not control its shape.

The fact that the problem is happening with a new coupler might be coincidental. You might try putting your stock coupler back on and seeing what happens to confirm/deny this.

My hunch is that the tighter coupler exposed a wear issue elsewhere in your shifting. I say this because I can't imagine a situation in which the coupler would allow you to get into 3rd but not 4th, or change the 5-4 shift. There is of course, a spring on that side (5-R side) that pushes the shift lever back towards 4th gear, and I'm thinking there might be an issue with that part of your shift linkage...

One more thought, if shifting is not working now, your mark is not likely to be correct anyway so you might need to move the coupler at some point in your repair...best to get over that and move it, it's not terribly difficult to dial it back in if you need to and your mark can get you quickly back in the neighborhood.