1998 yamaha 90aeto

[redyute]

i ran two boston wailers 17 footers with yamaha90hp motors on them.A 99 model and a 98 model,but the thing is that i get way more power from the 99 than i get from the 98,the boats are used for watersports activities.and i was wondering if it would be my only alternative to overhaul the engine to get the performance i should really get from it. But to me this is strange because the 99 model works much harder than the 98.

 

[steelespike]

Re: 1998 yamaha 90aeto

Id start with a compression check.<br /> Check throttle for full open, check timing,<br /> sync,compare props.Was there a gear ratio change<br />in 99,power head change?Motor trim,weight distribution,Any design changes on the boat.

 

[JB]

Re: 1998 yamaha 90aeto

I agree with Spike, Redyute.<br /><br />There are a lot of things that could reduce power in your engine that do not require an overhaul to correct.<br /><br />If it passes the compression check, overhaul the carbs and fuel pump, inspect the reeds and all other locations that could be leaking crankcase scavenging pulses and do a thorough link 'n' synch.<br /><br />Let us know what you find.<br /><br />Good luck.