Re: Weber check list
Posted: Tue Oct 18, 2011 6:48 am
If it's 2 adjacent cylinders that are showing problems then I think I'd start looking at the two plugs to see if they are showing signs of either over-rich or weak mixtures & then move on to the carb feeding them. Do you still have the fuel leak mentioned earlier in the thread ? If so that's the obvious starting point.
I have a fuel pressure regulator on my system, but I'm using an electric pump. With the standard mechanical pump I can't see over-pressure being a problem & I've never used a regulator with the OEM mechanical pump.
If it's a weak mixture then air leaks are the first point, although to get 2 chokes with leaks at the same time sounds like a carb mounting or O-ring problem. It's easy enough to see if petrol is getting into the glass bowl of the mechanical pump, after that it's just the filters that could be blocked at the carb. entry.
If it's too rich then my starter would be to make sure all the jets are screwed in properly then the float chamber valve followed by (already checked) float height or possible a leaking float.
I have a fuel pressure regulator on my system, but I'm using an electric pump. With the standard mechanical pump I can't see over-pressure being a problem & I've never used a regulator with the OEM mechanical pump.
If it's a weak mixture then air leaks are the first point, although to get 2 chokes with leaks at the same time sounds like a carb mounting or O-ring problem. It's easy enough to see if petrol is getting into the glass bowl of the mechanical pump, after that it's just the filters that could be blocked at the carb. entry.
If it's too rich then my starter would be to make sure all the jets are screwed in properly then the float chamber valve followed by (already checked) float height or possible a leaking float.