3000 RPM at Idle?

[deandec]

2100SR Maxum, 5.7L Mecury carborator, Alpha One and 19P 5 High Stainless prop and doel fin.

Boat worked great for two days at 6,200 ft elevation.

The last day the tachometer idled at 3,000 rpm at and 6000 rpm at 20 mph in less than two foot waves.

Boat was on a plane and operated fine when I first noted the high tach readings, I did not shut it down for fear of not restarting in small boat lake warning environment while returning to launch ramp.

Ran the engine in my driveway at 800 ft elevation and idle was 600rpm with forward gear at 1,500 rpm. Normal.

It appears no high RPM damage occurred, but why would I get such high Tach readings that last time on the water?

My guess is gauge error????

Thanks

 

[Bondo]

Re: 3000 RPM at Idle?

My guess is gauge error????

Ayuh,.... What did it Sound like,..??..??

I believe it would have become an Anchor if you ran it very long at 6 Grand.....

 

[WizeOne]

Re: 3000 RPM at Idle?

My experience is that tachs do that and often times do it intermittantly.
I could never get an explanation as to why. Check with a local instrument repair business or google the Mfgr and ask them.

My current replacement tach, which is now numerous years old, does that all the time.

 

[chiefalen]

Re: 3000 RPM at Idle?

I don't think you spun a prop. But to make sure run a line thru the middle of the prop and next time out when you pull the boat check the line.

Freekin, stikin, tachs, Mine just started messing with me too, was a lousy connection. Did you check yours?