|
The aluminum lambda fuel heads have a rubber diaphragm sandwiched and squished between the upper and lower halfs of the fuel head and the older cast iron fuel heads have a single stainless steel diaphragm in between the two halfs.
No sealant is applied to the rubber diaphram in the aluminum heads, it all goes together dry other than a little oil on the control plunger cylinder o-rings so they don't get torn while pressing it all together and the stainless steel diaphragm in the older cast iron fuel heads needs a thin layer of sealant on it or it would leak fuel.
One picture shows the old and new steel diaphrams. You can see traces of old sealant on the old one. The old one also had small dimples from control pressure spikes which can alter the fuel mixture. That's why some of the old RUF 930 fuel heads had a pressure damper installed in the control pressure line to smooth out the pressure changes when on and off the throttle quickly.
|