300/440/550 Pop off question

[Flyboy]

So I have a piece of junk 550 the has been a pain in the butt to get tuned. I have a sbn 44 with 120 high, 100 low, needle and seat 2.3 with dull silver spring which the manual says should put the pop off at 20psi but I just check and I'm getting 10.... So should I get a new needle seat and spring or did I screw something else up?

 

[DAG]

double check your spring, does it have 2 flat coils at the top? More than likely you have a shiny in their.

http://www.x-h2o.com/attachment.php?attachmentid=62363&d=1213727719

 

[Flyboy]

hmmm...I will have to check that out. I was messing around with it again the other day and I had to push the needle in other wise it wouldn't build pressure. I'm thinking I just need to get a new needle and seat and spring.

 

[schicks]

do you have a mikuni pump? are you lubing the needle with wd40..need to compress the spring and spray some in to make sure the rubber tip is getting wet on the needle. Make sure that the pump line is not leaking where you hook up to the line nipple, I had to clamp mine...kept getting a little leak throwing off the pop off. also make sure you plug the other carb lines good as well.

 

[wmazz]

It wouldn't surprise me if someone cut the spring. Many shops will do this when the ski comes in for repair
for being difficult or impossible to start.

Check the pop-off pressure with the carb inside a gallon zip-loc bag, and be sure to use gasoline, or a light
oil product (wd-40) to see if it is just leaking.



Bill Mazz