Tach Help?

[Greg Duggan]

Hey all,

last season my tach started to act funky. The needle would bounce and not hold steady at any given RPM. This season it was dead all together, no bounce no readings. I ordered the same replcament tach from BPS and replaced..... Same results no reading.

So, any ideas for me? i am not a motor guy so beyound electrical issues i am out of my area of expertise.



GregD

 

[Dan J.]

Could be as simple as a corroded lead on the block. (Should be three on your Merc: ground, ignition and reading. A two wire tach will even be easier with just ground and read.) Check connections on the powerhead coil/rectifier lead, ground and return. Good luck!

 

[Greg Duggan]

easier said than done. i just took the cowl off. what the heck is going in there i will never know.

this is an 06 Opti 135. The amount of wires and molex connectors in is astonishing.

i did a double check under the dash. I definitely have power to the tach and the back light powered up. If i have to, i will let the dealer look at this at the end of the season...







GregD

 

[Dan J.]

Now that you've narrowed it down to a specific Mercury, is it the Smart Craft tach, Teleflex, Farina,...? I wholeheartedly suggest that if you are not comfortable sourcing the leads (especially on an Opti) that your dealer take a peek at it for you. Your Opti has built in safeguards (rev. limiter, trim peak, and others) with the ECU which makes reading your tach more of a novelty for the operator than a necessity, particularly if your rig is running good within the operational perameters you have experienced in the past. If you have a list building or need a 100hr. service, etc., you may want to add the tach issue to that list and have your dealer tech do it all at once. Just food for thought. Good luck!

 

[Greg Duggan]

Dan,

i feel the same about the tach being a novelty. i have been without it since last July. Not a big deal really. thought if there was a quick fix, then it would be worth the effort to make it work again.

I will wait for the year end winterization service to have it looked at.

Thanks for the input.



GregD