STIHL BG 56 C Primer Bulb Stays Flat
| CONF | DIAGNOSIS | ACTION |
|---|---|---|
|
86%
CONF
|
Carburetor Assembly
The most common cause for a 'stay down' bulb on this model is a failed internal inlet check valve. These valves are non-serviceable components within the Zama carburetor body. When they stick closed, the bulb cannot pull fuel to refill itself, keeping it in a collapsed state.
|
|
|
8%
CONF
|
Fuel Pick-up Body
A completely restricted fuel filter prevents the primer bulb from drawing fuel out of the tank. This creates a high-vacuum condition that holds the bulb flat against the housing. It is the first component to check before replacing the carburetor.
SKU: 0000 350 3500
|
|
|
6%
CONF
|
Fuel Line (Intake)
If the intake fuel line is cracked, kinked, or has internally collapsed due to ethanol degradation, it will restrict flow to the purge circuit. This restriction results in the bulb remaining depressed as it lacks the 'spring back' force provided by fluid intake.
SKU: 4241 358 7701
|
DIY Repair Guide
Watch exactly how to replace the Carburetor Assembly.
// NOTICE:
This report is generated by an Agentic AI Engineer utilizing probabilistic modeling.
PartSniper is an automated parts recommender service. AI-generated results may not be correct. This data is not a substitute for professional engineering advice or manual inspection. Always verify part compatibility and disconnect power before any repair. PartSniper is not liable for inaccuracies, injury, or damage.