915 grinds going into gear

[TeeJayHoward]

My '81 911 SC has an issue. I'll pull up to a stop light, pull the shift lever out of first into neutral, and sit there while the light is red. Once it turns green, I'll try to put it back into first, and it will grind as though my foot is not on the clutch. I'm positive that I've got the clutch pedal all the way to the floor. Once I'm moving, I don't seem to have much difficulty shifting (The 915 still resists going into other gears, but doesn't grind). It's just from a full stop that the issue occurs.

I'm assuming that there's a way to adjust the friction point for the clutch - also that the issue is one that can be resolved by adjusting the clutch. Does this sound correct or is this a common issue with a different resolution? Are there any troubleshooting steps I could be taking to narrow down specifically what is broken or misaligned?

And if the clutch pedal just needs to be adjusted, where is that done - at the tranny or the pedal box? Is there a write-up I missed?

[Steam Driver]

Sounds like a dragging clutch to me. Probably worse going into reverse isn’t it?

Adjustment is made at the transmission.

[Superman]

Adjust the clutch. Done underneath the car.

I was just thinking of how important it is to get these cars maintained and adjusted properly before making decisions about what upgrades to make. These clutches work almost unimaginably smoothly when the parts are refreshed and adjusted. So....before someone imagines they need a different shifter, replace the coupler and also the clutch disk, release bearing, pressure plate, guide tube, fork and cable. My guess is that the owner will feel the car does not need to shift any better.

[Rodsrsr]

Originally Posted by Superman

Adjust the clutch. Done underneath the car.

I was just thinking of how important it is to get these cars maintained and adjusted properly before making decisions about what upgrades to make. These clutches work almost unimaginably smoothly when the parts are refreshed and adjusted. So....before someone imagines they need a different shifter, replace the coupler and also the clutch disk, release bearing, pressure plate, guide tube, fork and cable. My guess is that the owner will feel the car does not need to shift any better.

Facts....

[gduke2010]

My clutch went out a few months after buying my car. The symptoms were the same. I was out of town on a drive and tightened it up. Seemed fine going into first gear. However, I was about 50 miles from home and the clutch was completed gone by the time I got home.

Your situation sounds similar. But, could easily be something else.

[gduke2010]

I tightened at the tranny. If it’s your clutch, this fix won’t last long. Before this happened there were no symptoms, the clutch seamed to fail almost without warning.

[gduke2010]

Oops see you do have a new clutch.

[911obgyn]

Clutch needs to be adjusted according to bentley manual, and adjust the stop at floorboard.

[cabmandone]

Next time you drive the car and come to a stop do as you stated above but when trying to go to 1, first pull down into 2 and then go up into 1 and see what happens. Before I did my 1/2 refresh on my transmission, it would always grind if I came to a stop light and put the car in neutral then tried to go up into 1. I started pulling down into 2 then up into 1 and it would work every time.

[Tinkerer]

Mine goes into 1st smoothly while rolling since replacing the synchros. Spent a lot of time changing the other stuff mentioned above before getting to this point but it was all worth it

[Alex599]

I’ve got a grind once every five times I go into reverse. All I do is bleep the throttle before engaging reverse. Never ground since. I always assumed my reverse syncro was toast but I’ll look into the adjustment now.

[Showdown]

I occasionally have a bit of resistance/grind getting into first. If I put it into second for an instant and then first there’s no problem. This is usually when at a dead stop like a traffic light where I’m in neutral for a while.

My synchros are probably due for replacement (car has 55k miles) but that’s not on the budget for this year so double clutching and hitting second before first will suffice.

Other than that, it runs from 1st-5th and 5th-2nd flawlessly- I can shift as fast as I’m able without issue.

[yelcab1]

Originally Posted by Alex599

I’ve got a grind once every five times I go into reverse. All I do is bleep the throttle before engaging reverse. Never ground since. I always assumed my reverse syncro was toast but I’ll look into the adjustment now.

Reverse syncro can never be toast... there is no syncro on reverse.