Fuel issues 1986 Suzuki DT115

[Numlaar]

Hey all,

Having a few problems with my motor...

First question:

1. Can anyone tell me what the factory setting is for the idle/air mix needle at the top of the carb(s)? (My wonderful seloc manual, just says they are all different, and doesnt even give you a starting point). I have 4 freshly rebuilt carbs I need to get setup correctly...
I need to know # of turns out from fully seated.

Second thing, After having the carbs rebuilt, it is now doing something very strange... it is sucking the fuel bulb flat... now before you go with the obvious "vent", I have already tried that... in fact, I have tried the onboard tank, two seperate portable tanks, and 3 different combinations of fuel hoses/primer bulbs, all new, ALL with the vents OPEN and its still doing it... Heck, I even took the dang gas cap completely off one of the portable tanks, and it will still suck the hose down...

I am wondering if its related to the mix question above, because it sucked down 3 gallons of gas in like 15 mins... its never done that before...

So looking for some direction on both issues... what the setting should be on the carbs, and ideas on why its gulping so much gas, and sucking the hose down.

 

[99yam40]

Re: Fuel issues 1986 Suzuki DT115

As a rule of thumb a 115 HP motor will burn 11.5 gallons of fuel at WOT in a hour. 1/4 hour should be close to 3 gallons at WOT.
Check the fuel pump pressure and vacuum as listed in the frequently asked section of the forum to see what is going on with the fuel delivery system, could be a bad primer bulb fuel intake screen if it has one in the tank or anti-siphon valve causing a restriction. Make sure the fuel pump does not have a bad diaphragm and leaking fuel into the crankcase
Hope you find some one with a manual to give you the specs, if not buy one yourself

 

[Numlaar]

Re: Fuel issues 1986 Suzuki DT115

Thanks,

I found the carb settings, and will be working on that...

I am also going to try to direct plumb the entire fuel line without any dis-connects...

After fiddling with the system, it seems they might be creating the vacuum from not opening up all the way... I'll let you know.