RPM Gauge & Vibration - The Hull Truth

casey344 · 08-10-2006, 08:46 AM

2000 Regal, 2100LSR, Faria Gauge package

Running 30 mph, engine sounds fine, RPM gauge showing in the red at 5,000 rpm. Stop and restart engine, 30 mph, gauge shows 3,000 rpm.

What would cause the gauge to read incorrectly?

billinstuart · 08-10-2006, 08:59 PM

Engine??

casey344 · 08-10-2006, 09:17 PM

Engine is a merc 260 I/O ... New prop is installed and will see if vibration goes away.

Could the RPM gauge and the vibration be correlated?

prockvoan · 08-11-2006, 07:09 AM

Is the engine reving up that high?If it is,yes,due to the fact that the prop bushing is slipping.With the boat out the water,in gear and the key switch OFF,try to turn the prop by hand to see if it is slipping.

casey344 · 08-12-2006, 07:48 PM

No engine doesn't sound like it's working any harder than usual.

Removed the dinged up 23P Aluminum and installed a new Quicksilver 19P Stainless, going to try it out tomorrow. The spike in RPM only happened once the last time out. I've had other 'Faria' gauges fail, wondering if the RPM gauge is the latest.

thataway · 08-12-2006, 07:57 PM

RPM guage (tachometer) is often driven by the alternator. Be sure that the alternator is working properly. Why are you dropping 4" in pitch on the prop? This quite a large drop, and truely may allow the engine to over rev.

casey344 · 08-12-2006, 09:43 PM

I know someone with the same boat (same engine) running a 19P ... he said it drastically improved his holeshot, and hasn't mentioned any problems over rev'ing. I'm bringing my original prop with me just in case there are problems. As I'm sure you can tell, I haven't experimented with props at all ...

prockvoan · 08-13-2006, 09:05 AM

Changing from an alumunn prop to a ss wheel,you have to drop pitch alot due to the fact that a alumunn wheel flexes out of place when under load and a ss wheel flex is alot less!