Yamaha 50hp 4-stroke starting problems

[stinga]

Recently bought a second hand quintrex with 50hp 4s yam. Over the last couple months when using it, the motor will never crank on the first attempt even if it has only been turned off for five minutes. It is an electric start and seems to turn over ok but it just doesn't start. On the second attempt it usually goes but sometimes it takes 5 or 6 attempts before it fires up. The primer bulb doesn't ever get all that tight and am not sure if the valve is letting fuel leak back out of the motor. It seems like it must be a fuel problem but stuffed if I know. I haven't had much experience with 4-strokes so any help on this matter would be much appreciated.

Thanks, Stinga

 

[stinga]

Re: Yamaha 50hp 4-stroke starting problems

Might just add that it is a 2000 model.

 

[WillyBWright]

Re: Yamaha 50hp 4-stroke starting problems

Some models have automatic chokes that disengage if you give it throttle. Make sure that you leave the warm-up lever alone if you have one of those. If you hear a click when you toggle the choke switch, then it's manual.

Primer bulbs are prone to failure, especially aftermarket ones. If you have a genuine Yamaha fuel line, it should be okay. But gas deteriorates those eventually as well. Once the motor is warm, you shouldn't need to pump the primer bulb at all. Once gas is in the carb bowls, it can't syphon back out.

 

[Cavanaugh68]

Re: Yamaha 50hp 4-stroke starting problems

Does any one have a suggestion for a good starting battery for a 2007 Yamaha 4 stroke 50HP?(MCA and CCA)