1971 100hp Evinrude lacks RPMS

[Flying Kidney]

I have a 1971 V4 2 stroke 100hp Evinrude that is lacking top end RPMs. Currently it is topping out at 3000 rpm. Both the slow speed and high speed idle adjustments are fixed. I.E.: there are no set screws. I've check the jets - they are clean. Funny thing is while running wide open, I closed the choke valve about 3/4 and the boat took off. Obviously holding a linkage while crusing isn't acceptable. Occassionaly the rpms will jump up for a second (just a second). The engine wants to go. Any ideas of how I can break the chains and let this baby go?

 

[DJ]

Re: 1971 100hp Evinrude lacks RPMS

FK,<br /><br />You are starving for fuel.<br /><br />I suspect a fuel line restriction (tank, hose, tank vent) or your high speed jets are clogged.

 

[Flying Kidney]

Re: 1971 100hp Evinrude lacks RPMS

Thanks D.<br /><br />I pulled the plugs, giving me access to the high speed jets. They seem to be crystal clear. I'll take a look at the fuel lines.<br /><br />I had it out this morning. The surges (more rpms) at high speed seem to be happening more frequently.