Stihl 015AV won't idle

[Ifitaintbroke]

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Hi folks

This is my first post so I hope it's in the right place!

I've rebuilt an old Stihl 015 AV and it will start at half throttle, run at full throttle but as soon as I lift my finger off the trigger it dies.
I've tried adjusting the idle speed screw, but the result is always the same: no idle.

Am I right in thinking that this means not enough fuel is getting through?
What should I try next?

Any suggestions appreciated!

 

[Lakeside53]

It's likely that you have an air leak and the only way the fuel gets any pressure is by vibration of the tank when you rev it up. Bascially you have lost impulse pressure. Crank seals? Carb gaskets?

 

[Ifitaintbroke]

Thanks for your reply Lakeside. How do I check the crank seals and carb gaskets for leaks? Pour something in the crankcase and see if it leaks out?

 

[Lakeside53]

You need to pressure test the crankcase..., and more likely, a vacuum test as that's where seals usually fail. Try to get a service manual, or search this site for "pressure test" or
or "pressure testing".