Ski falls on FACE. Need Assistance!

I’ve recently had the engine of my 1995 Wave Raider (stock 62T) rebuilt from the bottom up by a professional shop. Both cylinders were compression tested today and both came back at 160.

I wanted to try to rebuild the carbs myself to try and learn more about how these things work.

I rebuilt both carbs with Mikuni kits and ensured they were clean and assembled properly. I did test the pop off pressure on carbs and it was popping off at 55.

Today I put the ski in the water and started it to get the new engine break in process going. Riding at idle seems to be fairly good, but as soon as I pull the throttle (1/4) to try and accelerate Up to 5MPH, the engine starts to go and then dies right off but doesn’t stall.... so there is no acceleration.

I assume this has to do with my carb rebuild job but I’m not really familiar with how to troubleshoot/correct this issue. I stoped into my local Yamaha dealer and they said they would need to look at it but would likely cost over $1k to diagnose and tun!!!! WTF!!!

Does anyone have any steps/recommendations on how to correct this?
 
Turn the screws on the carbs out to 1.25 turns each.
Thanks Quince. You think I should do that on both carbs?
right Now the low speed screws are turned out 5/8 from seated.
do you think turning it out by 1.25 will make a huge difference?

sorry for the questions, I’m pretty new to all this stuff...
 

Quinc

Buy a Superjet
Location
California
yes turn the screws out on both carbs. It sounds like you are not getting enough fuel. Also did you hook up your fuel lines correct and remember to put the pulse line back on?
 

Quinc

Buy a Superjet
Location
California
If the ski runs better turn the screws out to 1.5 turns. Then 2 turns. If it gets worse go back to 1.5 turns. Then try only turning either the top or the bottom screws and test again.
 
If the ski runs better turn the screws out to 1.5 turns. Then 2 turns. If it gets worse go back to 1.5 turns. Then try only turning either the top or the bottom screws and test again.

I attached a picture of Carb 2, i marked where the fuel lines are connected.. I believe they are correct but i’m not 100% on that.
 

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smoofers

Rockin' the SQUARE!!!!
Site Supporter
Location
Granbury, TX
Did you replace the needle arm in the carbs? If it isn't adjusted properly, the diaphragm on the square side of the carbs can hold the needle open when you bolt the diaphragm cover back on. Something else to check if Quinc's suggestion doesn't help.
 
Did you replace the needle arm in the carbs? If it isn't adjusted properly, the diaphragm on the square side of the carbs can hold the needle open when you bolt the diaphragm cover back on. Something else to check if Quinc's suggestion doesn't help.
Hey Smoofers, When I took the carbs apart, it looked fairly clean inside. I did clean out a bit of junk but not much. The needle arm in the carbs was replaced with what came in the kit. I’ll try Quinc’s adjustments first before I tear the carbs apart for the third time!!! Lol.
Thanks
 
i usually start with 1 turn out from closed on both high and low adjustment screws. i think 55 psi is the correct popoff as well. sounds like you just have a simple screw adjustment and youll be set
 
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