The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Bill Conquest on October 14, 2015, 12:42:52 AM

Title: tachometer failure
Post by: Bill Conquest on October 14, 2015, 12:42:52 AM

Hi everyone, My tach on my 79 R65 recently quit working.. are there any first things to check before sending it off..it was rebuilt by Palo Alto about 4 years ago.
Thanks, Bill

Title: Re: tachometer failure
Post by: Barry on October 14, 2015, 03:37:40 AM

The first thing I'd check is the impulse connection from the coil to the tach. There should be a black wire from terminal 1 on the front ignition coil to pin 5 on the tachometer connector. For the tacho to work you must also have +12v on pin 6 and an earth on pin 8.

Title: Re: tachometer failure
Post by: Bill Conquest on October 15, 2015, 12:59:23 AM

That's great info, Barry..i'll check those and if i'm lucky it'll be one of them..mahalo!!
Bill

Title: Re: tachometer failure
Post by: Bill Conquest on October 17, 2015, 10:58:38 PM

well, I checked all the connections and wires and they are good...I guess it's off to the repair shop..

Title: Re: tachometer failure
Post by: Tony Smith on October 18, 2015, 01:22:48 AM

Quote

well, I checked all the connections and wires and they are good...I guess it's off to the repair shop..

I have managed to restore one to life, a long time ago by replacing the capacitors on the power supply side. i can't be more helpful that that I'm afraid as it was so long ago. Also i am aware that there are at least two 'series' of R65 Tacho and one has some discrete components that can be carefully removed and replaced at home, and the second uses surface mount components - I lack the equipment, the eyesight or the hand-eye coordination to attempt them.

Title: Re: tachometer failure
Post by: Bill Conquest on October 20, 2015, 12:44:24 AM

Thanks Tony...I've been tempted to take a crack at fixing them but always change my mind when I look inside!  I would probably do more damage than good.. any thoughts about the best place to send it to?
Thanks, Bill

Title: Re: tachometer failure
Post by: Tony Smith on October 20, 2015, 04:31:55 AM

Quote

Thanks Tony...I've been tempted to take a crack at fixing them but always change my mind when I look inside!  I would probably do more damage than good.. any thoughts about the best place to send it to?
Thanks, Bill

Sorry, no.
Fleabay is your friend, as recently as yesterday there was one for sale.

Title: Re: tachometer failure
Post by: marcmax on October 20, 2015, 09:43:04 AM

Bill. Send me a PM. I have two tachs sitting in a box in the garage. Both are off of an LS, one is 1982 the other is 1984. I have switched to digital gauges and they have been sitting there for a couple of years.

Title: Re: tachometer failure
Post by: Bill Conquest on October 22, 2015, 01:08:26 AM

Thanks everyone for the feedback!
Bill