Volvo Penta 50 GLE Innacurate and Fluctuating RPM

"Only 30 hours on engine. Ran

"Only 30 hours on engine. Ran great last year. Started right up after winter but idle RPM fluctuates between 1000-1500 RPM with noticeable surging. With constant power setting, RPM can jumpt from 3000-5500 with no engine RPM change. Also, sometimes with throttle almost full forward, engine not producing thrust like normal. RPM shows 5000+ but boat sounds like 2500 RPM and speed confirms that would be closer to what it is producing. Could something with winterization cause this? (Bad gas, water in tank, something loose on engine?) I also had hull and outdrive painted. Could something be taped or painted over that would cause this?"

"I have a 2002 Glastron with a

"I have a 2002 Glastron with a 220HP 5.0L SX outdrive and I am having similar problems. My problems are electical. Tachometer fluctuation is most prevelent when the engine compartment blower is turned on.

Could it be a bad ground? Is the blower motor sending voltage back into the system?

Also, my fuel gauge fluctuates quite a bit. This doesn't seemed to be tied to the engine compartment blower.

Any feedback?"

"Stephen, you seem to have a f

"Stephen, you seem to have a faulty connection in the tachometer wiring. Check that the tachometer wire (usually a grey wire) attached to the (-) of the coil is tight and that the connector is clean.

Ken, your problem could be a defective fuel sender or a faulty connection. Make sure that the connections on the pink wire going between the sender at the tank and the gauge are clean and tight. Also, check the + and - wires behind the gauge in the console: if the connections are loose or rusty you could get the symptoms you described."

"El Pescador,

Thank you for

"El Pescador,

Thank you for the reply.

What do you think of my tachometer fluctuation when I turn on the engine compartment blower?

Ken"

"I think that if the connectio

"I think that if the connections and wiring are in good condition that should not happen. It could be that the tachometer is picking up some "noise" due to wiring or connections in poor condition, or due to the blower wire and the tachometer wire being too close together, or...?. You may also want to check that the selector switch (or jumpers) in the tachometer for number of cylinders and 2-4 stroke is set correctly."