BenzWorld Junior Member
Date registered: Jun 2007
Vehicle: 1973 280c
Location: Seattle, WA
Mentioned: 0 Post(s)
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280c W114 Carb/Fuel Issues
I've got a 1973 280c with some fuel issues. This car has been sitting off and on for a while before I got it. My uncle drove it for a time but stopped after it started leaking blue smoke. We eventually tracked it down the vacuum leak and fixed it. Since then the car has sat off and on while I stored it at my parent's house during college.
After fixing my vacuum leak problem and putting in new plugs, the car ran really well. I left in the car of my family for three weeks immediately after that. When it got back to me, it was running very wonky. Exhaust smells like fuel and I have to really pump the gas to get the car started. Also it idles rough after the car warms up and the choke goes off.
I'm pretty sure a lot of my issues are carb related. The idle and mixture screws were adjusted for poor vacuum. So I'm assuming with more air getting pulled in so it is now running lean. Does anybody with some experience in Solex 4A1 carbs want to give me a quick run down on adjusting the mixture? I've heard that you need to disable the egr valve to do this correctly. Is that true? I can just pop the vacuum line off the egr valve and plug that line closed to do that right?
On a somewhat unrelated note, I've heard they purposely put smaller jets on these carbs to make them pass emissions in the US. Some have said upgrading to larger jets meant more efficiency and power. Does anybody have any experience with this?
Please don't suggest a Holley conversion. I can't afford that right now and I'm trying to keep it as stock as possible. A mercedes tech a few years back said the carb head looked good with no warping and to torque the nuts to specification if I ever popped it off to rebuild it.
I'd also like to clean out the fuel system since it has been in storage so long. I crawled under the car today but the fuel filter doesn't seem to be in the usual position (American cars) next to the driver side door. I've also heard there is a fuel screen in the tank itself. I'd like to do this all in one go so I don't have deal with the mess/waste of gasoline twice. I couldn't find a stock fuel filter so I'm unsure what I'm looking for. What is the location of the fuel filter on this vehicle? Any advice on taking the tank off, what to use to flush the lines, and how to clean out the tank?
Thanks for all your help.