Tachometer Bad?

[ziggy2]

Farina tach needle Is pegged beyond 7000 and will not operate. Is there a way to determine if tach is bad or there is a problem on the sender end?

 

[achris]

Remove the sender wire (should be grey unless you're not working on a post 1981 Mercruiser), and see if the tacho reads 0 with the power on.

What are we working on? (engine, not boat)

Chris......

 

[Fun Times]

Also you could try tapping on the gauge with power on to see if it frees up and also try Exercising a switch on the back of the gauge a few times while ensuring to put the Arrow back on the matching engine cylinders your boat has… The gauge should generally have marks on it somewhere suggesting the number of cylinders.

 

[ziggy2]

Remove the sender wire (should be grey unless you're not working on a post 1981 Mercruiser), and see if the tacho reads 0 with the power on.

What are we working on? (engine, not boat)

Chris......

Tach reads beyond 7000 with key off and jumps slightly towards 7000 when key is turned on. Removing the signal wire made no difference with key on or off tach stayed at beyond 7000

 

[achris]

Sounds like a failed tacho...

 

[ziggy2]

Sounds like a failed tacho...

Any recommendations for a new tach. I need it operating so I can sell the boat.

 

[achris]

A cheapie off eBay?

I find the tacho, despite being the biggest instrument on the panel, the most useless. Oil pressure, coolant temperature, even the voltmeter, give useful information that can be acted upon. What the engine speed is, is entirely dependant on how fast you want to go.

Chris....

 

[nola mike]

A cheapie of eBay?

I find the tacho, despite being the biggest instrument on the panel, the most useless. Oil pressure, coolant temperature, even the voltmeter, give useful information that can be acted upon. What the engine speed is, is entirely dependant on how fast you want to go.

Chris....

And how loaded the boat is, and what prop you have on there. Trim gauge is most useless.

 

[achris]

And how loaded the boat is, and what prop you have on there. Trim gauge is most useless.

On any given day you can't change the loading or the prop. They are part of the 'fixed data' package. You can only change the boat speed using the throttle. Tacho is nice and pretty and, totally 'unfunctional'...

 

[Bondo]

Farina tach needle Is pegged beyond 7000 and will not operate. Is there a way to determine if tach is bad or there is a problem on the sender end?

Ayuh,..... Welcome Aboard,.... Sounds like a 2 stroke outboard tach,.....

 

[QBhoy]

Hi. I’ve seen this happen loads. Also seen them go back to working normally once you start the engine and give it a flick. One of my boats that spends most of the year in storage does it all the time on the faria gauge. Right at this moment…it’s sitting showing 1500 rpm…but I know if I go use the boat…it will sort itself out as soon as the engine starts.

 

[ziggy2]

Decided that tach was toast. I purchased a new one on ebay which I am hopeful will work ok. Size is ok and has pulses instead of pole settings. Mine is a 12 pole setting so I assume a 6 pulse will be ok. Thanks for all the feed back.

 

[achris]

Pulses is for outboards. Make sure you get a tacho that suits a stern drive...