Checking tachs accuracy

[Beck]

I have a tach that plugs into my control box but when it was new it started out at 800 rpm I adjusted it to 0. Then noticed that the paperwork said it would 0 itself after powered up. I took it to a friends house with same type control box, ran his motor to a perticular rpm then switched tachs. and adjusted. His motor was a 70 hp Johnson, mine is a 48 spl Evenrude. I will say the boat I had it on, 14' flat, it ran aprox. 5400 rpm. I switched it to a Tims custom 16x54. Hadn't put in the water yet still riging it up. Is there a better way to check the accuracy?<br />Thanks,<br />Beck

 

[Silvertip]

Re: Checking tachs accuracy

Sure! Borrow or rent an automotive timing light with an inductive pickup that clamps over a plug wire. Be sure the timing light has the built-in tach. Set the rented tack for the number of cylinders and then multiply x2 since you have a two stroke.

 

[Beck]

Re: Checking tachs accuracy

Upinsmoke,<br /><br />Thanks for the info. When I get my boat back together I will check with a local rental place to see if they have timing light with a tach.<br /><br />Thanks again,<br />Beck