915 shifter fore/aft freeplay?

mmack · 04-27-2009, 08:02 PM

I've been lurking for a few months, but I'm new to my 911 (December), and this is my first post. Please be gentle.

The car in question is an '86, 915 with factory short shift and a Seine Systems gate-shifter (using the centering spring, but not the 1/2 gate itself - different story).

I got in the car today and the usually-tight (for a 915) shifting felt loose. I'm noticing about a half to three quarters inch of free play, fore and aft, when in gear (any gear), or in the neutral plane. I may be losing my mind, but I don't think the play was there yesterday. The car has new shifter bushings.

I guess the questions are: 1) do they always have that kind of fore/aft freeplay (i.e., am I losing my mind)?, and 2) if not, what most likely "let go" to make the difference between tight yesterday and loose today?

Obligatory photo of car in question...
And useless photo of shifter, in case anybody wants to draw on it...

Any input is appreciated. Thanks,

Mark

Fishcop · Fishcop's Garage

Hi Mark (and welcome)

There are three bushings in the linkage between the shifter and the gearbox (all in the tunnel) that make a remarkable difference to the shifting feel of your car. They're relatively cheap, but expect a full day in the garage removing a seat, carpet and console to get to it all

Use the search function and enter "shift"+"linkage" and you'll see there are a heap of threads on this topic.

Fishcop · Fishcop's Garage

Oops - double post.

911pcars · 04-28-2009, 12:41 AM

Mark,
Check the set screw at the front of the shift housing. These hardly loosen since a large lock nut prevents rotation, but if it's loose for any reason, it will allow the shift lever "box" to move fore and aft and without transferring movement to the shift tube.

A more likely possibility is that the two-piece shift lever is about to separate. They're permanently joined at the factory with non-permanent epoxy. Move the shift boot out of the way and observe the shift lever/linkage movement.

Check also the shift lever bushing holder where it attaches to the front of the shift tube.

Okay, I'll ask. Why did you not install the Gate Shift kit top carrier plate?

Sherwood
Seine Systems

mmack · 04-28-2009, 03:57 AM

Thanks guys.
John - I'll see which ones my mechanic replaced. I don't think he took a seat out to get to anything, so maybe there's one or two that were untouched. Will check the searches as well. I'm still confused by the overnight change. If it were a bushing issue, I would think it'd be a slow decline(?). This just seems like something slipped.

Sherwood - The shift lever separated a few months ago (that was fun). The yellow line in the picture is the reference line my mechanic used when he tack-welded the other side. It's solid now. I'll check the bushing holder as you mentioned.

Regarding the top carrier plate - when I bought the car in December, the plate was installed, but for some reason, it was creatively 'bent' by the PO. It forced the 1-2 shift into some nasty contortion. Now that I've checked out the site, I see how it should look (nice and flat with the tabs sticking straight up). I'll definitely order a new plate.

I appreciate the responses.

Mark

Brian 162 · 04-28-2009, 05:26 PM

Check the nut and bolt which holds the shifter rod to the shift coupling. I had the same problem and what I found was the bolt was stripped allowing the shift rod to slide along the coupler.

mmack · 04-30-2009, 08:42 PM

I checked the movement of the shifter in relation to the movement of the coupler, and I found that even a brand new stock coupler allows a surprising amount of fore/aft slop. It's appears as if the pin that holds it together (with the black smooth ends on each side) is quite a bit smaller than the opening in the coupler that it passes through.

I looked at the Stomski and WEVO PSJ pieces on our host's site. I'll do a search for some more info on the advantages. Thanks again for the responses. I think I've identified what's going on.

Mark

911pcars · 04-30-2009, 09:27 PM

The factory bushing for the shift coupler is oval, with the wider ID in the fore-aft direction. This is supposed to reduce vibration transferred from the gearbox to the shift lever. Some folks prefer tightening this up. The 914 versions are round. Some aftermarket bushings are made of plastic; some metal. Other aftermarket products replace the entire shift coupler with an aircraft/commercial CV joint - all solutions to one degree or another in order to reduce play in the shift linkage.

Sherwood