SQLGuy

Hi folks,

A few months ago my car was in the shop for new TT bearings. While all that was out, my mechanic installed Roger's Delrin bushings in the shift coupler, and a new ball cup insert in the front piece. Last weekend the shifting got really bad. I finally got to look at it yesterday, and the problem is that the front insert has popped out of the end piece (i.e. the insert is still on the ball, but is no-longer in the cup).

Are there adhesives I can/should use when pulling the cup back down onto the insert, to keep it from doing this again?

Thanks,
Paul

Dave928S

It sounds like the cup mightn't have been properly pushed into the socket. The socket has a ridge which tends to stop the cup popping out, as can be seen in the photo. Glue isn't normally used, and may only act as a lubricant when it gets hot and cause it to pop off again.

Here's a pic of a ball cup pressed hard in .... it needs to be seated into the metal cup first and then pushed down onto the ball on top of the TT.

SQLGuy

My mechanic says that, if the insert hadn't been fully in the cup, it would have popped out at the first shift, and not a couple of months later. The insert was new, the cup old.

Any other thoughts on why this would fail, besides the insert not being fully inserted into the cup? I'll take another look to see whether the ridge has been torn off the insert or something....

I've heard of people putting tie straps around the shaft, but I thought that was more to protect against the coupler coming off of the ball.

Lizard928

The insert is for the clutch release arm and not really for the shifter lever.

When replacing it is best to replace the ball cup as a fixed unit. Or install one of my short shifters to prevent this from happening.

cfc928gt

Paul,

The proper part is a one piece unit, 928.424.005.01, not two piece with a replaceable insert. You will probably need to strap it to keep it in place since I don't think glue would work over time plus if you have to go so far as to take it out to glue it you might as well replace it with the right part.

Dave928S

A bit like the rear coupler is sold as one part and separate bushings aren't shown in PET ..... but you can get the genuine replacement factory bushings to put in them (or delrin).

PET shows the front coupler it as an assembly, like it does the rear coupler ... but that doesn't mean you can't put a replacement plastic cup in it, if there's nothing wrong with the metal component.

The plastic cup is shown as a separate item on the clutch release arm, and not on the front shift rod .... but the parts are identical.

Dave928S

If the insert wasn't fully pushed fully home it still may have hung on to the ball for some time, and not necessarily come off at 'the first shift'.

Because of the location the plastic cup gets quite hot, and that's a factor in its deterioration, and can also be some of the reason they come off. Are all your heat shields in place?

Lots of owners replace the ball cup bushing and they're fine ... yours should be too. As a precaution use a new one and make sure it's pushed fully home, before pulling it down on the ball.

I don't see any logical reason to replace the complete front ball cup joint (or a complete rear coupler) if they are still in good condition, when replacement bushings are available.

Mrmerlin

928 motorsport makes a metal cupped front shift coupler,
its a Bit..h to put on but it will last the life or the car

SQLGuy

Hi Dave,

Yes, the heat shields are all in place and in good shape. From what I remember, the insert itself looks OK. I may look into one of the metal ones, though, if I'm going to have tear apart as much as I think I'm going to have to to get things set straight.

Cheers,
Paul

AirtekHVAC

Colin, is your shifter the one Jim is installing on U-Tube?

NM...I answered my own question by re-watching it...also noticed you replied to my question on the clip...lol..

Dave928S

Wouldn't hurt to do that to be certain that you won't have a repetition of the issue, as they are a PITA to get at; or go for Colins setup which can be done from the top and eliminates that front joint.

It really is a matter of opinion and individual choice.

SQLGuy

The only thing that worries me about Colin's setup is that Porsche went to such pains to keep the shift linkage isolated from the body. I'd like to understand better why they thought that was important before undoing it.

WallyP

Perhaps they didn't want the movement of the power train relative to the body to put pressure on the transmission shift mechanisms...

depami

Or maybe it was simply an assembly issue. Keep all linkage on power train/running gear and just lower body onto it?

Lizard928

Ding ding ding, we have a winner.

It made assembly easier. If you have good mounts, and good delrin bushings in the back you will have no additional vibration or noise from my shifter design.