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Discussion Starter #1
Got a Walbro Wt-603 that I rebuild very carefully. Still has an issue of the prime bulb not filling with fuel and obviously the engine is not getting any fuel. Can anyone help me figure this out? Where are you Silver talk to me :)
 

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After you replace it start the bike with the chain off and hold it wide open throttle turn the fuel mixture screw in and watch the exhaust smoke you will see the blue cloud get lighter and lighter as you turn the screw in once the blue clears up you know it's lean then back the screw out so there is some blue in the smoke not a lot that will get you in the ball park then you can start tuneing it under a load just turn it in or out 1/8 th of turn at a time for the most power and it will be good
 

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Discussion Starter #5
After you replace it start the bike with the chain off and hold it wide open throttle turn the fuel mixture screw in and watch the exhaust smoke you will see the blue cloud get lighter and lighter as you turn the screw in once the blue clears up you know it's lean then back the screw out so there is some blue in the smoke not a lot that will get you in the ball park then you can start tuneing it under a load just turn it in or out 1/8 th of turn at a time for the most power and it will be good
Man that’s awesome info Mr. Kitty. I can’t wait to do it. Thank you!
 

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Looks nice and comes with everything you need

Yeah that’s what I though and the extra items look good too. I can use that starter pull for when I convert to round style Pawl in the future as well.

Ok so you’re not gonna believe it. I got the Walbro running an hour ago. Through process of elimination I figured out what was wrong. A bend in the lever was enough to get fuel flowing and I think there might have been small leak on the outlet hose on the connector end which might have contributed to getting the primer to fill better... I just cut off 1/4” of the end and reattached and I think it helped... please correct me if I’m wrong on that part.

About you’re advice on the adjustment screw. The Walbro comes with the high and low screw adjustment. I figured the low adjustment is likely to be for idle am I right or is it more for take off? And what method is the easiest to taking off the chain with the least disassembly?
 

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L is for idle H is for high RPM those chain saw carburetors don't have mutch throttle response In between they are basically a all or nothing carby

The rotorey weed wacker Carby has better throttle response

I whould try both and see what one you like better
 

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Looks nice and comes with everything you need

Yeah that’s what I though and the extra items look good too. I can use that starter pull for when I convert to round style Pawl in the future as well.

Ok so you’re not gonna believe it. I got the Walbro running an hour ago. Through process of elimination I figured out what was wrong. A bend in the lever was enough to get fuel flowing and I think there might have been small leak on the outlet hose on the connector end which might have contributed to getting the primer to fill better... I just cut off 1/4” of the end and reattached and I think it helped... please correct me if I’m wrong on that part.

About you’re advice on the adjustment screw. The Walbro comes with the high and low screw adjustment. I figured the low adjustment is likely to be for idle am I right or is it more for take off? And what method is the easiest to taking off the chain with the least disassembly?
Nice job, that's what these bikes are all about, figuring out what's wrong and fixing it.
 
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