Hi! I have a 1973 VW Beetle with a stock 1600cc DP Type I.
A few months ago I replaced the fuel hoses with 4.8mm Diameter hoses that I got from a local parts store. This weekend I replaced the oil bath air cleaner with a stock OEM paper element air cleaner. Then I started it up. It had a lower idle after changing the air cleaner. Could the extra volume of intake air have attributed to this? I raised the idle but did not adjust the carb. It seems to be performing OK now.
I also noticed an occasional air bubble passing through the fuel filter and an almost lack of fuel in it. Ususally at idle spped, the fuel filter is almost fuel. Could the smaller diameter fuel hose be acting like a pinched fuel line and be restricting the fuel flow? Could this cause extra wear on the fuel pump?
I sent off for the correct diameter, 5.5mm Diamter, fuel hoses today. Thanks! JP