Primer bulb drawing air

[adw]

just another thought, the fuel hose with fuel filter on the end, which connection on the carb have you connected it to?

[Stubby]

9 hours ago, adw said:

just another thought, the fuel hose with fuel filter on the end, which connection on the carb have you connected it to?

I would connect it to someone else's saw ?

[Phil H]

just another thought, the fuel hose with fuel filter on the end, which connection on the carb have you connected it to?

The stubs are different sizes, fuel tube from the tank flows into the uppermost stub on the carb.
The tube that flows from carb to primer bulb is a smaller diameter and is half way down the carb.

Pic of actual carb attached.

I have owned the saw from new, ~10 years, it has done very little (occasional home use) and was spot on until the neighbour used it & put bad fuel in it a couple of years ago.

I'm suspecting a poor quality (ebay) carb kit but want to eliminate other issues first

[Stubby]

If he, the borrower bloke , used old shite fuel it might have nipped up . have a look at the piston through the exhaust .

Edited August 21, 2020 by Stubby

[Toad]

Are they the original or oem fuel lines?

[Phil H]

If he, the borrower bloke , used old shite fuel it might have nipped up . have a look at the piston through the exhaust .

Doubt it nipped up, engine starts and runs sweet, the problem appears to stem from air being drawn into the carb.

[Phil H]

Are they the original or oem fuel lines?

Yes but they appear good & are tight onto the carb stubs, I have trimmed a bit off tge ends.
No air is drawn into the carb via the tube from the tank but air is coming out of the stub that goes to the bulb when the bulb is released.

[Toad]

48 minutes ago, Phil H said:

Yes but they appear good & are tight onto the carb stubs, I have trimmed a bit off tge ends.
No air is drawn into the carb via the tube from the tank but air is coming out of the stub that goes to the bulb when the bulb is released.

Numerous pumps don't change this? Sounds like air getting into the system through the carb then.

[Phil H]

A slow release of the pump no/little air, fast release =lots of air.
Numerous pumps make no difference, one or two slow pumps makes it air free again.
Must be the carb then, I just wanted confirmation that I'm not missing something obvious.

[Stubby]

5 hours ago, Phil H said:

A slow release of the pump no/little air, fast release =lots of air.
Numerous pumps make no difference, one or two slow pumps makes it air free again.
Must be the carb then, I just wanted confirmation that I'm not missing something obvious.

Have you tried fitting a new primer bulb . It would be a cheap way to eliminate my suggestion earlier of a punctured primer ?