Wiring Diagram For Two Gas Engine Tachometers And A Syncronizer

December 21, 2021

1986 vdo engine synchronizer wiring diagram??

http://item.mobileweb.ebay.com/viewi...d=400310123161
I have the above synchronizer that isnt working. On the back on the left are 2 male spade terminals. One has a " ground" symbol so that is self explanatory. Above that is another labeled "R" . I'm thinking that is "positive"?? On the right there are terminals for each engine which is self explanatory as well along with the ground symbol but there is also a "+" terminal. I can't figure out why it would need 2 " hot " wires so now I'm thinking maybe the "R" is not positive after all. Anyone have this gauge or a wiring diagram to help me how to wire it? If you click on the description it will show you a picture of the back of the gauge.

Last edited by sammi; 06-21-2013 at 05:11 PM.
Re: 1986 vdo engine synchronizer wiring diagram??

The unit that you show is for a 24 VDC system. Is this correct for your application???
Most of these Syncronizer units sense tachometer pulse input... so whether gas or diesel engines, you'll have a pulse signal to electronic tachometers.... either via gasoline engine ignition pulse, or diesel engine alternator pulse.

The Syncronizer unit will require 2 inputs (Port and Stbd pulse signals)......., and may also require power and negative sources.... although I can't confirm that.

If you connected the pulse sensing terminals to POS, you may have damaged the unit.

.

Rick ... aka Ricardo..... AQ series Volvo Penta repair
Portland, Oregon
28' SDN F/B w/ twin Volvo Penta 5.7L DP drives

"Intellectual growth should commence at birth and cease only at death." Albert Einstein

Please... no PMs! Post your questions on the forum.
Re: 1986 vdo engine synchronizer wiring diagram??

have you tried calling VDO's Tech Support Group?
They'll want the catalog number off the sticker
Re: 1986 vdo engine synchronizer wiring diagram??

Mine is the 12 v version. But wiring it is the same.the backs are identical. Pulse wires were hooked up and never changed. They appear to be correct. Everything makes sense except for the "R" terminal. I dont know what that is. 2 grounds(why 2 idk but it has the ground symbol). Two from tachs(one each) and a "+". That's it.

Last edited by sammi; 06-25-2013 at 04:37 PM.
Re: 1986 vdo engine synchronizer wiring diagram??

The "R" and the "gnd" terminal below it are for the internal red light ... are the dip switches set correctly?
Re: 1986 vdo engine synchronizer wiring diagram??

OK! Well that solves the riddle. The "+" doesn't have a wire to it. I didn't want to do anything there since I wasn't sure why there would be 2 positives. I should be able to hook a 12 volt source and be good to go.
Re: 1986 vdo engine synchronizer wiring diagram??

Thanks for everyone's help. I found the wire that was supposed to be hooked to the pos. Terminal and I'm up and running again. I always felt a synchronizer was not necessary on my boat because you can tell by ear when they are in or out of sync but I hate not having stuff work on my boat.