So, about six months ago I reported on by success fixing the leaf blower.
That had a bad carb and stuck piston ring. So, I finally decided to do the
same with the Troy-Bilt convertible weed whacker. (It has a shaft that
converts between whacker and a lawn edger widget). It hasn't run in a
decade. IT is still in really good shape, wasn't heavily used.

I took the carb apart and first thing, the fuel hoses were shot, disintegrating.
The carb had a little bit of fuel gunk in it, not surprising since it was left
with fuel to evaporate all that time. I fully disassembled it, except for
removing one welch plug. Sprayed it with carb cleaner, blew it out with
compressed air, rinsed the fuel tank, cleaned the fuel filter. I thought
I'd have to get new fuel lines, but then I realized it was the same size
as the fuel line I had bought for the leaf blower! So, I checked for
compression with my finger, pulled the plug and checked for spark, put
the new hose in, put it back together. Started on the first pull.

I revved it up, all was good. But then when run at high speed it starts
to struggle, like it's not getting gas, then it quits. Put the choke
on give it a pull or two, and it starts right back up. And that is
what it was doing a decade ago when it wouldn't run! Doh! So now I'm
thinking it's likely the primer bulb. It seems to have a lot of air,
like 50% in it when it quits. Also, pumping the bulb, I can watch fuel
in the lines and it looks like it moves back and forth, instead of in
one direction. I'm thinking that it probably has a check valve in it
that's kaput and it's probably also leaking air. But there is no sign
of leaking any fuel. Being old, it should be replaced and I have one
on order. But in the meantime, some questions:

This bulb is separate from the carb. Do they typically have a check valve
in them? There was a little plastic widget in the fuel line, but on the
parts diagram it calls it a "connector" and from the size and shape, I
think that's all it is. I didn't use it, opting to just run one length
of fuel line instead. I think it's purpose is just that it's a bit easier
to put together with two pieces of line and then join them. But since
I don't have the new primer bulb, I'm thinking that I will get it fired
up, then remove the primer bulb and bypass it with that old connector.
I figure once it's full of fuel and good to go, it doesn't need the primer
and I can find out for sure if it is the primer without waiting for the
new one. Does that sound like it should work?