[ToMang07]

OK.....

So left for work today, and about 1/4 mile down the road I notice my tach is not working correctly.....(Rivco)

I was running about 2,200rpms....and It was reading about 1,000. I dont know why it would do that....It would seem to me if it was broke, it would just not work......not just read incorrectly.

It DID seem to climb/fall with how many rpms I was running....but always seemed to be 1/2 or less of the actual RPMs.

Any Ideas of why or what to look for? :dontknow:

It is less than 1 year old, and I have NEVER had a problem with it before.

Any input/experience would be helpful. Thanks in advance. I have NOT had a chance to look at it yet...working doubles the next 2 days, too. :banghead:

 

[Scool3yDoo]

what kind of tach do you have?
i have a barons and just had an issue with it not reading and very shakey. i traced the wiring out to find the ground wire was broke and it was vampired together. i removed the vampire clamp and solder the wires together. fix it.
it is shakey less then 2000 rpms but above that runs fine.

i would check the wiring and for vampire clamps.

 

[ToMang07]

Rivco

 

[ShowTime65]

..........my boat tach does the same thing until I smack it a time or two. Then, it reads as it should!

Show

 

[X-Brit]

OK.....

So left for work today, and about 1/4 mile down the road I notice my tach is not working correctly.....(Rivco)

I was running about 2,200rpms....and It was reading about 1,000. I dont know why it would do that....It would seem to me if it was broke, it would just not work......not just read incorrectly.

It DID seem to climb/fall with how many rpms I was running....but always seemed to be 1/2 or less of the actual RPMs.

Any Ideas of why or what to look for? :dontknow:

It is less than 1 year old, and I have NEVER had a problem with it before.

Any input/experience would be helpful. Thanks in advance. I have NOT had a chance to look at it yet...working doubles the next 2 days, too. :banghead:

The Rivco tach takes input from both coils. It is probably reading 50% because input from one coil has been lost. Either due to a faulty tach module or a bad wire connection. I would check the wires under the seat that are spliced into the coil wires near the ECM. These types of connectors are not very reliable. Soldering is recommended.

 

[ToMang07]

The Rivco tach takes input from both coils. It is probably reading 50% because input from one coil has been lost. Either due to a faulty tach module or a bad wire connection. I would check the wires under the seat that are spliced into the coil wires near the ECM. These types of connectors are not very reliable. Soldering is recommended.

what kind of tach do you have?
i have a barons and just had an issue with it not reading and very shakey. i traced the wiring out to find the ground wire was broke and it was vampired together. i removed the vampire clamp and solder the wires together. fix it.
it is shakey less then 2000 rpms but above that runs fine.

i would check the wiring and for vampire clamps.

Yup....sure enough, ONE of the TWO vamp clips lost the wire...It did NOT cut through....Just came loose. I guess I'm going to have to give in and solder the wires....I have never done this before, but alas, I guess it needs to be done. :dontknow: I need to get some shrink-wrap for the wires I assume....I hate playing with electronics. :banghead:

 

[X-Brit]

Yup....sure enough, ONE of the TWO vamp clips lost the wire...It did NOT cut through....Just came loose. I guess I'm going to have to give in and solder the wires....I have never done this before, but alas, I guess it needs to be done. :dontknow: I need to get some shrink-wrap for the wires I assume....I hate playing with electronics. :banghead:

The best way is to CAREFULLY cut away the insulation for about 3/8" without cutting the inner wires. Then wrap the tach wire around the exposed wire and solder them together. Use liquid insulation to cover up the joint followed by a couple of wraps of tape.

 

[ToMang07]

The best way is to CAREFULLY cut away the insulation for about 3/8" without cutting the inner wires. Then wrap the tach wire around the exposed wire and solder them together. Use liquid insulation to cover up the joint followed by a couple of wraps of tape.

What???
:dontknow:

 

[X-Brit]

What???
:dontknow:

Liquid insulation; it's liquid vinyl or something similar. It comes in a can with an applicator brush. You can get it in marine supply and some autoparts stores.

 

[X-Beast Driver]

I had a Rivco Tach on my C model that was hard wired in (no vampire clips) and I never had a problem with it.