Max 2600RPM???

[Ralph 123]

Re: Max 2600RPM???

Jim,<br /><br />You might want to consider a process of ellimination starting with the easiest/ least expensive and moving on from there<br /><br />Here is a way to check the gear ratio of your drive so you can eliminate it from the list of possibilities:<br /><br /> http://www.mercstuff.com/drivegearratio.htm <br /><br />Then go out and beg or borrow a 15p prop and eliminate that as the possibility.<br /><br />Then go out an spend the $ for a new carb.

 

[navigator336]

Re: Max 2600RPM???

Has anyone checked the emulsifing jets? These are the little holes you see when looking down into the carb throat to the fuel bowl side of the throat. If one is plugged, the engine will run fine up to a certain rpm and then bog down a little as you open the throttle butterfly more because the gas is not getting properly emulsified prior to the venturi. If one or both look plugged or restricted, run a piece of copper wire through it. Then in neutral run the rpm's up to 2500+ with the spark arrestor off and put your hand over the throat to create a super high vacuum. Pull your hand off quickly (before the engine dies) and repeat two or three times. This will generally suck the material you dislodged with the wire out of the delivery circuit. If this was the problem, expect to see no lag or bog and about 15 -20% improvement in fuel efficiency.

 

[jimmmy]

Re: Max 2600RPM???

My brother-in-law put a 17 pitch prop on yesterday. Got it up to 3200RPM and 32 MPH. Hope to try a 15 pitch now!

 

[jimmmy]

Re: Max 2600RPM???

Ralph and Bondo are very wise indeed.....<br /><br />The problem was the wrong gears in the outdrive. Some bonehead had put the wrong outdrive on the boat. Runs great 4500RPM and 40 MPH now!<br /><br />Thanks ppl