Adding a tach

[firedawg662]

I'm new to boating and have learned alot in this forum, but I can't find the info I'm looking for about installing a tach. I have a 1985 Bayliner 1710 Trophy Bass Boat (I think) with the same year 85hp Force motor. My question is can I use an automotive tach since there is a tach lead on the electrical block on the engine? The unit I bought says its not for marine use, but isn't a 12 volt system a 12 volt system? I need the tach since I put a larger prop with 2 degrees less pitch and do not want to over rev the motor.

 

[NYBo]

Re: Adding a tach

It won't work, at least not properly. You need a tach that works with a 20-pole stator, which is getting hard to find. I don't know if anyone still makes them. I had to score a used one off eBay for my boat.

 

[Jiggz]

Re: Adding a tach

Tachs are rated not only in voltage but also in the number of poles from the signal source. In this case you will need a 20 pole tach. Of course, there is always those magnetic signal tachs or pulse tachs like tiny tach.

 

[pnwboat]

Re: Adding a tach

Here's one that says it will work with a 20 pole stator. Might want to contact the seller because one of the pictures of the back doesn't show a 20 pole setting.

Faria Nantucket Matte Gray 7K Gas Outboard Boat Tachometer Tach Tacho Universal | eBay

Or this one.

Faria U s Marine Tachometer Gauge 20 Pole TC9819A Marine Boat | eBay

 

[jerryjerry05]

Re: Adding a tach

pnwboat, both of those tachs will work.

 

[Jiggz]

Re: Adding a tach

20 Pole tachs are getting harder to come by with each passing year