Husqvarna 550XP fuelling/running issues.

[jonathanfp123]

I am looking for some advice about what the issue may be with my 550xp.

I have had it 5+ years now and it's never missed a beat. Tried to use it the other day and it would only run if I held the choke on. The second the choke came off it would die.

The primer bulb was not filling so I assumed that. Had it off and gave it a look and it seems to work fine - push the bulb in and cover the inlet hole and the bulb won't come back up, and can feel suction against my finger, suggesting it has no splits or leaks. Great news.

I reconnected it (inlet only) and again it wouldn't draw in any fuel. However, if I loosen the fuel cap it draws in fuel no problem.

This made me think there is a breathing issue stopping the bulb drawing out any fuel.

I've gently blown through all the fuel and breather lines and there is no restriction. However when I tried with the fuel tank inner vent (p/n 501 15 29-01) it was extremely hard to blow through.

It doesn't appear to be visually blocked, but could this be the cause of my issues?

 

*I should note that the carb was removed pretty early on for easier access to the tank lines so I could check them independently.

 

Thanks all

[Mark_Skyland]

It sounds like you may have an issue with the carb. If a check valve is faulty it will draw air in through the carb rather than fuel. Its worth checking the carb diaphragm for tiny holes as this can cause the same issue. You may need to hold it up to a light.

Have a look here