Thread: Carb Question(Walbro HDB)

I have two Walbro HDB carbs that spit gas(a lot) out the opening. I've rebuilt both of them but still no luck. Finally rebuilt a 3rd carb and it ran perfect on the same saw I had tried the other two on. I wonder if they are shot as I see nothing else I can replace. Any thoghts would be appreciated. Hate to trash them as I'm out of spares.

Check if the needle valve is holding 6-7 lbs of pressure.Your problem could be there and look at the inlet lever level.Check if welchplugs are not leaking.

Originally Posted by HiOctane

Check if the needle valve is holding 6-7 lbs of pressure.Your problem could be there and look at the inlet lever level.Check if welchplugs are not leaking.

Wish I had the means to do a pressure test but alas don't have a tester. As far as welch plugs, my breakdown schematic doesn't show any, as far as I can tell. I keep hearing about them in other threads but maybe someone can confirm if they exist on the Walbro HDB and if so where they are? Thanks for your thoughts. I've double checked the metering level so I'm stumped.

Originally Posted by redunshee

Wish I had the means to do a pressure test but alas don't have a tester. As far as welch plugs, my breakdown schematic doesn't show any, as far as I can tell. I keep hearing about them in other threads but maybe someone can confirm if they exist on the Walbro HDB and if so where they are? Thanks for your thoughts. I've double checked the metering level so I'm stumped.

Check if the inlet tip has not a kinda small ride around it.If so,you need a replacement because it wont hold fuel correctly.