Not getting full power and has some bog

I have a 1993 superjet with a stock 62t out of a raider with dual 38s. Ski has 150psi in each cylinder, good spark, always use 90 oct non eth, new jets 130 main 70 lower, new needle and seat with whatever the stock springs are im pretty sure. I'm pretty sure the adjuster screws are out about 1 1/4 turn to 1 1/2 turn. I tuned the carbs at the ramp and ran the ski between adjustments and checking the spark plugs each time. Ski was running great for a few months then recently started to bog and give me trouble starting after it was hot. It doesn't have the low end or mid range power it used to and it feels like it won't go WOT. After jumping wakes it really bogs then clears up after a little. My reeds are stock and in great shape too. I don't know what else to check. And I looked at the fuel pump in the carbs they are clean. Took the in line fuel filter out too and the pick up in the tank is clean.
 

Quinc

Buy a Superjet
Location
California
If the stator was going out wouldn't it show low spark on a spark test?
Not sure if you could tell the difference between good and bad spark? But normally when the electronics are on there way out they start having issues once warmed up. To save money you could swap just the lightening coil with another oem coil.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
62T stators and flywheels are known for having issues when hot , the magnets in the lighter 62T flywheels are weaker and the source coils go bad as in pretty much all Yamahas across the board, the fix is to install a 61X ignition , heavier flywheel, stronger magnets better stator coils , an all around better ignition system , I am not saying this is your problem but it could be.
 
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62T stators and flywheels are known for having issues when hot , the magnets in the lighter 62T flywheels are weaker and the source coils go bad as in pretty much all Yamahas across the board, the fix is to install a 61X ignition , heavier flywheel, stronger magnets better stator coils , an all around better ignition system , I am not saying this is your problem but it could be.
Thanks I'll look into that
 

hornedogg79

dodgin' bass boats
Think he got that a little backwards. 62t has the heavier flywheel with better magnets and stator coils. Not saying the stator isn't your problem.
 

hornedogg79

dodgin' bass boats
Gotcha, I might let it get up to temp when it acts up then try doing a spark test. I'm hoping I can get away with replacing a coil or maybe messing with my spark plugs wires
If boggling after a jump, that's where I'd start. Trim them a bit and install msd crimp on plug ends.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
Think he got that a little backwards. 62t has the heavier flywheel with better magnets and stator coils. Not saying the stator isn't your problem.
Depends on which 62t flywheel but yes they are heavier but only by .2 lbs on the 61x with the thick ring gear , regardless of all of that the magnets on the first years of 62T's were weak which made it really hard to diagnose, the only real way was if you had a good flywheel handy to compare it to and even then the test was subjective , the magnets on the 62T flywheels are smaller being an internally cased type magnet versus the nice big external screw on magnets on the 61X flywheels .

I will go along with your spark plug cap theory as I have run across quite a few bad spark plug caps on Yamaha's over the years and it sure can't hurt anything to try it.
 
Also would be a good idea to pull your water box out and shake it. A broken baffle can cause a bog like that too.
Funny you say that, I was thinking it could be a bad waterbox. I saw some soot outside of some rivets so I re riveted and sealed it. I even put some pipe in place of the waterbox to run it without one and still ran the same. I'm going to mess with the plug wires this week I will keep you guys posted. Thanks for the replys
 
Depends on which 62t flywheel but yes they are heavier but only by .2 lbs on the 61x with the thick ring gear , regardless of all of that the magnets on the first years of 62T's were weak which made it really hard to diagnose, the only real way was if you had a good flywheel handy to compare it to and even then the test was subjective , the magnets on the 62T flywheels are smaller being an internally cased type magnet versus the nice big external screw on magnets on the 61X flywheels .

I will go along with your spark plug cap theory as I have run across quite a few bad spark plug caps on Yamaha's over the years and it sure can't hurt anything to try it.
It's the easiest thing to try to so I'll start with that and move deeper if I have to. Thanks for the replys
 

Quinc

Buy a Superjet
Location
California
As long as they let air into the tank then no. Also you should cap one of those off and put a oneway valve on the other.
 

WFO Speedracer

A lifetime ban is like a lifetime warranty !
Location
Alabama
Unless one was laying in the bottom of the hull and sucking up water no , and yes I have seen that happen before.
 
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