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Yamaha 70hp low rpm problem in drive

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Rory ONeill

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"i have issues with 1988 70hp

"i have issues with 1988 70hp in drive mode with the rpms not going over 3000rpms, but in neutral it will rev to 5800rpms, how can i adjust for the full rpm range in drive?"
 
"Most motors will rev high in

"Most motors will rev high in nuetral and you must not do that! ----- Do a compression test and a spark check, spark must jump a gap of 7/16" or better.You are likely running on 2 cylinders."
 
"it is a 2 stroke model, i am

"it is a 2 stroke model, i am not familiar enough with this engine to know the normal cruising rpms, i thought it was pretty slow cruising speed. is this the normal rpm range on a 1988 2-stroke motor? thanks"
 
That motor should run at 5300-

That motor should run at 5300-5500RPM at full throttle.So is this a new installation? Did you just get the motor?? What boat is it on??
 
"i purchased the 24ft grumman

"i purchased the 24ft grumman pontoon with the yamaha, the coastguard max recremended hp is 90hp. i have taken the boat out for around 12hrs now and thought i should be getting more power out of the motor, but I haven't had a boat in years... i do apprieciate the help"
 
"one last thought, can i rule

"one last thought, can i rule out that it maybe a problem with the tension on the throttle cable at the side mount controls? thanks again"
 
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