george44

Tachometer on '79 911SC (VDO Electronic) runs fine for about 20 minutes and then freezes. Knock on the glass but doesn't move. Comes to zero upon shutting down. Any ideas? I've pulled it out to check the wires, everything seems in order. Thanks,

George

John Brandt

send it to North Hollywood speedometer or Palo alto Speedometer.
they both do a good job

Bill Gregory

Since it's electronic, you might check to ensure it's getting a signal. Otherwise, as John suggested, it sounds like repair time. I've used North Hollywood and was pleased with their service on my speedometer.

george44

Hi John and Bill, thanks for responding. I know about those places and there is also a guy in Toronto that does VDO repairs. My only problem is that I don't understand how comes it works for 15-20-25 minutes and then freezes suddenly at whatever RPM it happens to be at the time. Good suggestion, stupid me, I will check to see if there is signal when it stops, at least I will know for sure it's the tach and not the sender.

George

davis911s

George
Try swapping your Tach out with one that you know works???

See if the same thing happens?

I have one that I am not using for the next few months, but mine has not worked for a while. I am sure the tach is fine I think it is the wiring in mine.

That would be the best thing to do if it were me. Save spending $ until you KNOW the prob.

Email me if you want


Shawn

davis911s

George I can't get ahold of you on email, your account is down?

I haven't heard back from you about my tach. I got the email saying you received it but nothing since. I hope everything is well.

Email me or post here if you have finished with my tach and will be sending it back please.

Shawn