3 gallons or less in your tank!!

[1nc 2000]

Do you have pictures and instructions on how to do this. I’m having the same issue with mine. But it only happens after 3 or 4 hard pulls using my MSD Launch Master. It happens even with 1/2 to 3/4 full tank. Not sure if the pump it getting hot from the 2 step, or if it just can’t recover fast enough. It doesn’t do it all them time and cleans itself out, but then does it again. Just started happening this year after adding the MSD. That said though I have never in the past just lake raced all day like I did last weekend.

https://ty4stroke.com/threads/knock-light-causes.156051/page-9

 

[1nc 2000]

I measured the hole in the tank where the stock return line is with grommet removed. Its just a hair over 1/2" hole.
You need to remove the fuel pump housing from the tank to drill thru top cap. Watch out for the hoses on bottom side so you don't drill those by accident.

 

[1nc 2000]

Yamaha grommet and black elbow.
Also purchased 6 feet of 1/4" fuel injection hose and three clamps. I just cut the old fuel return line at the top of the tank and put a bolt in it with a clamp around it.

 

[BlueByYou2000]

Yamaha grommet and black elbow.
View attachment 159044

Thanks a ton man

 

[BlueByYou2000]

I measured the hole in the tank where the stock return line is with grommet removed. Its just a hair over 1/2" hole.
You need to remove the fuel pump housing from the tank to drill thru top cap. Watch out for the hoses on bottom side so you don't drill those by accident.

The pics in the link are confusing. I’m only seeing 1 fuel line in the first pic (the clear line). Then I’m seeing a loose line not connected to anything. I just looked at mine and only see 1 line, where is the return line in stock form?

 

[1nc 2000]

This is how mine is. Return line installed.

 

[1nc 2000]

The pics in the link are confusing. I’m only seeing 1 fuel line in the first pic (the clear line). Then I’m seeing a loose line not connected to anything. I just looked at mine and only see 1 line, where is the return line in stock form?

In stock form the return line is on top left of tank.

 

[DMCTurbo]

Yamaha grommet and black elbow.
Also purchased 6 feet of 1/4" fuel injection hose and three clamps. I just cut the old fuel return line at the top of the tank and put a bolt in it with a clamp around it.
View attachment 159044

Thanks 1nc. Gotta love this forum! I'm going to do this mod while I have my tank off.

 

[Phatboyc]

Is this still an issue on newer models? With no knock light on stock sleds it could be bad.

 

[max rolph]

soo i just had this problem on mine... i have a quarter tank of fuel and had it up on the stand, i went to start and would not start yet my guage says 1/4-1/3, looked at fuel pressure guage and was at 0, took off stand and turned key on and the fuel pressure went up to 45....WTF soo the pick ups must be in rear of tank.

 

[justinator]

Pickups are towards front of tank. You may have one that is turned or not sitting flat. Remove sending unit and you can their position. Might be drawing air somewhere too and thats why you couldnt get prime with fuel at front of tank.

 

[max rolph]

you mean pickups are at rear of tank.... that would explain on the stand starvation, is there a way of adding pickups... but i guess it would then draw air if skis are up.

 

[DMCTurbo]

you mean pickups are at rear of tank.... that would explain on the stand starvation, is there a way of adding pickups... but i guess it would then draw air if skis are up.

 

[DMCTurbo]

 

[1nc 2000]

The fuel pick-up lines in the tank do not connect to the pump. They dump into the cup the pump sits in.
It works on the scavage system dumping fuel into the pump cup and them the pump sucks the fuel out of the cup to the engine.
This cup can be sucked dry from the pump.
Re locating the fuel return line to dump into this cup helps ensure their is no starvation of fuel from the pump.