Benzworld.org - Mercedes Benz Discussion Forum - View Single Post - 280 Running Excessively Rich, Copious Black Smoke

cheapold280ce · 01-31-2008, 08:25 AM

EUREKA EUREKA EUREKA,
Thank you for your post and thanks Nutz for your reply. As you know I am bring alive my cheap euro. I am having the same problems as noted below. I start car and if fires up even at 15 degrees outside no problem. But it runs Super rich. I mean there are black soot spots in my driveway. I pulled plugs and they were BLACK with carbon. I tired to feed as much air as possible backing out the 3mm hex screwing out CCW and raising idle. Still ran rich.
Now here's the BIGGY I know I have a restricton on my return. When I changed tanks the return line was completely clogged from the rust from old tank. I ran a coat hanger through end of it and got to damp part where old fuel was still in line so maybe I have an 1/8 in dia meter return or maybe my retun is still clogged. I figured that the return pressure would push out the crudge from return line but it was pretty bad. I assume it did since engine ran.
Here's my plan, Nutz let me know what you think. Disconnect the return line at fuel distributor (FD). Attach a fuel hose from FD to 5 gallon gas tank this will do two things drain my fuel tank and unrestrict the return line. I should be able to adjust the fuel mixture with return running to gas can (correct ?).
When gas tank is empty I can pull off return line and cut hard metal return line further back (more forward in car) behind the resriction and connect a longer flexible fuel line to tank this should unrestrict the return and correct the rich problem.
Poleaxed did you change or clean or flush your gas tank? My 280CE tank was toast I am thinking you might have the same restiction I have. Does your car leave black spot's on driveway does it run that rich?

01-31-2008, 08:25 AM	#3 (permalink)
cheapold280ce BenzWorld Extremist Date registered: Sep 2007 Vehicle: 1978 280ce euro bought for $300.00 Location: d.c. Posts: 1,108	NUTZ saves the day again EUREKA EUREKA EUREKA, Thank you for your post and thanks Nutz for your reply. As you know I am bring alive my cheap euro. I am having the same problems as noted below. I start car and if fires up even at 15 degrees outside no problem. But it runs Super rich. I mean there are black soot spots in my driveway. I pulled plugs and they were BLACK with carbon. I tired to feed as much air as possible backing out the 3mm hex screwing out CCW and raising idle. Still ran rich. Now here's the BIGGY I know I have a restricton on my return. When I changed tanks the return line was completely clogged from the rust from old tank. I ran a coat hanger through end of it and got to damp part where old fuel was still in line so maybe I have an 1/8 in dia meter return or maybe my retun is still clogged. I figured that the return pressure would push out the crudge from return line but it was pretty bad. I assume it did since engine ran. Here's my plan, Nutz let me know what you think. Disconnect the return line at fuel distributor (FD). Attach a fuel hose from FD to 5 gallon gas tank this will do two things drain my fuel tank and unrestrict the return line. I should be able to adjust the fuel mixture with return running to gas can (correct ?). When gas tank is empty I can pull off return line and cut hard metal return line further back (more forward in car) behind the resriction and connect a longer flexible fuel line to tank this should unrestrict the return and correct the rich problem. Poleaxed did you change or clean or flush your gas tank? My 280CE tank was toast I am thinking you might have the same restiction I have. Does your car leave black spot's on driveway does it run that rich?