TACH METER ???

[buddyle]

got my boat out the lake today, it ran very well, strong and fast...it ran about 35 mph...here is the concern i have with the tach on my boat. i max out the throttle, it ran about 35 mph, but the tach needle went to the maximum rpm (tach meter is 7000rpm). is that normal? when it on neutral, it run about 1000 rpm. so how would i test this to make sure that my boat running right, or should i even concern about it? motor ran very well. thanks.

 

[roscoe]

Re: TACH METER ???

Glad the boat is running well now.<br />Your '89 85 hp has 10 magnets under the flywheel.<br />Each magnet has a north and a south pole.<br />10 magnets = 20 poles.<br />You need a tach that can read the signal produced by 20 poles, a tach known as a "20 pole tach."<br /><br />Some tachs have a selector switch on the back that allow it to read the signal 8, or 12, or 20 pole.<br /><br />I read in your other post that you bought a Honda tach.<br />I doubt that it will work for you and give you accurate readings.<br />I don't think Honda ever made a 20 pole tach.<br /><br />Look at the back for a selector switch, you might luck out.