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#1 Tachometer not working

Posted: Sun Oct 21, 2018 4:48 pm
by TheDampMan
Hi all any help would be appreciated.
My tacho has 3 wires coming out of it
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The car loom to the tacho has a 3 pin block with 2 white and one green wire, the 2 white wires are bridged together allowing the car to run, the green wire has a 12v supply.
The car has electronic ignition.
Since owning the car the tacho has not been connected.
I have tried connecting the 3 wires to the connector without any luck.

#2 Re: Tachometer not working

Posted: Sun Oct 21, 2018 6:36 pm
by christopher storey
This is a sensing instrument of an early type. In standard form the white wire carrying the current from ignition switch to distributor is looped through a block, usually twice which is sometimes on the outside of the case, or alternatively sometimes inside the case, which provides a flux sensor to the circuit board on the instrument , showing by the frequency of its fluctuations the opening and closing of the points. The circuit board then provides this to a moving coil apparatus, the moving coil being powered by 12v from the green wire . Frequently, possibly even usually, even if properly wired these tachos will not work with electronic ignition

If you search for rvi and rvc tachos on this board you will find a fuller explanation, and suggestions about what to do

#3 Re: Tachometer not working

Posted: Sun Oct 21, 2018 7:10 pm
by Bfastr
Assuming thats a S2 tach, those wires are not original. maybe someone tried to convert it to work with the electronic ignition? and why are they partially stripped a half inch from the spade lugs? odd
the original had this type connector. have you opened up the tach to see whats going on inside?
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#4 Re: Tachometer not working

Posted: Thu Nov 01, 2018 1:06 am
by TheDampMan
Yes I think it has been converted to work with the electronic ignition, however im having no luck in getting it to work so I need it checked over and repaired has anyone got any recommendations of who to send it to?

#5 Re: Tachometer not working

Posted: Thu Nov 01, 2018 4:49 am
by mark10337
Do you know which type of electronic ignition you have?

#6 Re: Tachometer not working

Posted: Thu Nov 01, 2018 6:54 am
by abowie
TheDampMan wrote: ↑
Thu Nov 01, 2018 1:06 am
Yes I think it has been converted to work with the electronic ignition, however im having no luck in getting it to work so I need it checked over and repaired has anyone got any recommendations of who to send it to?
Speedograph Richfields in Notts. If you take the car to them with the tacho they may be able to get it working for you. My guess is it has been converted to a modern type.

#7 Re: Tachometer not working

Posted: Mon Nov 05, 2018 4:27 pm
by TheDampMan
All sorted and working now :bigrin:
Red cable + 12v supply
Black - negitive
Yellow - side of coil