Diaphragm membrane for Carburettor on VIRE 6/7 Tillotson

    The picture carburettor is not included.

Rubber fuel-level-diaphragm (old ones harden - increasing flooding/surging of power)

Restores diaphragm flexibility and gasket suppleness.

Fault Finding - Fueling

if your carburettor has been running fine, but you dont know this part has been changed in the last 4-10 years, then you should order this part, to maintain it's reliability. It loses it flexibility after 4-10 years because petrol attacks rubber.

the diaphram's job, is to keep the fuel level constant height inside the carburettor, regardless of flow, instead of a traditional brass float. 

symptoms of a defective diaphragm are:

• hard to start (fuel level too low)
• revs hunting (fuel level too low)
• lack of power in gear (fuel level too low)
• cannot start -no fuel coming through carb at all  (cannot flex at all to open valve)
• engine revs go up and down regardless of throttle (fuel level changing)

note, these symptoms are also similar if you have other carb defects, but most commonly they are caused by an ageing stiff diaphragm alone.

If you are having problems with carburation, or have an unknown carburettor to overhaul, be advised its likely that you will need more than just this diaphragm, maybe the fuel valve, gaskets or pump valves/diaphragm that come in the 'kit'. 

simple choice i advise you order:

1. DIAPHRAGM (this part) = carb was running fine, just want to keep up with 4-10 year service interval
2. CARBURETTOR KIT = carb was running fine, now has definite problems, leaking, starting etc
3. REFURBISHED CARBURETTOR = dont have the skills to overhaul nor a carb that was running ok
4. NEW CARBURETTOR = prefer the manual choke lever or want top reliability against internal saltwater corrosion or your carb is obviously too damaged exterior or corroded interior