'05 YAM 90 High idle

[get n skinny]

ok, two weeks ago i had new throttle and gear cables put on. next day after a half day of fishing everytime a cranked the moter up it would idle higher and higher. 3000 rpm is has high has it got one time. then when it would come down to around 1500 it would idle rough and cut off. of course it didnt do it when i took it back to the dealer that put the cables on. they turned a screw on the throttle linkage and it was fine for the rest of the weekend. this past sunday(two weeks later) it did the same thing. To night i let it run on the hose for a hour and couldnt get it to do it. idled at 7-800rpms fine. oh and while it was idlein at 1800-3000rpms the butterfly on the carb was shut and throttle was sitting on the idle screw. someone told me i have water in the gas, but i thought to myself how can that make the motor rev so high?

thanks

 

[robert graham]

Re: '05 YAM 90 High idle

Same motor as mine, only mine is a 1999. That's a curious problem, but if the idle control screw is against the stop and adjusted properly, then I wonder if the ignition timing is somehow getting out of whack. Are the throttle and timing linkages all hooked up and set correctly after the mechanic changed your control cables? Please keep up posted with what you find out on this and good luck!

 

[99yam40]

Re: '05 YAM 90 High idle

I agree that the timing is not advancing when it should. Easy to check with a inductive timing light when it acts up again.
I believe timing is controlled by the CDI unit with input from the Throttle Position Sencer. Not sure on your 90 but on my 40 it is internal to the CDI and is not replaceable, will have to replace CDI if that is the problem you find.

 

[get n skinny]

Re: '05 YAM 90 High idle

ok so i fished this afternoon and ran the boat from one side of the lake to the other and ran like it was new. i dont have a timing light to check but i did pull the plastic cover of the top of the motor and what i saw which i guess are two fly wheels and the big fly wheel. the two small ones have arrows on them and they where perfectly across from each other so i dont no. if it was the cdi box going bad could it reset everytime i cut the main battery off? which in turn only make it rev high after it heats up? is there a way to check the cdi box?

 

[99yam40]

Re: '05 YAM 90 High idle

all I am saying is when it is running high rpm at idle check the timing since you are saying that the throttle is not sticking open