Resurrecting a 1986 420SEL

[engatwork]

I've got the above listed car in the shop trying to get it running for a customer. The car has sat at a couple different non-MB shops for the past two years with a no start issue. So far I have found the tank screen plugged along with both fuel pumps being bad. The owner had SIX used fuel pumps and from what I can tell they are not any good either. I am going to try to take one apart and see if I can do anything to it to get it working. I pulled one set of fuel pumps off of another car (560SEL) he had at his house and the crap that came out of the fuel tank looked like used oil and had the consistency of honey. Needless to say the same stuff was in the fuel pump. Is there any fluid cleaner that I could possible put in the fuel pump to clean this stuff out. It is pretty nasty stuff. I'm going to hit him up for two brand new fuel pumps and see how serious he is about getting the car going. I get the feeling that he is not wanting to spend money on new fuel pumps so we will see. I can drop a little gas on the fuel distributor plate and the car starts and sounds good as long as the fuel last. In addition, looking closely at the fuel line at the fuel distributor the inside of the line looks good with no build up/varnish.

My hands still smell like that crap that came out of the tank. I can't stand the smell of bad fuel.

[oldsinner111]

Almost sounds like someone put sugar in his gas tanks.You can get carb cleaner or brake cleaner to clean pumps.

[pmckechnie]

First, be careful. I got into a 83 380SEL one time and at about $1300 of approved work, the man disappeared and left me with a car that still wouldn't run. It had set for about 10 years and he wanted to get it running because it was this fathers car. I told him up front that it would cost a lot and $1500 to $2000 was possible.
Now, If the fuel strainer was plugged then the tank needs to come out and be cleaned. Then new filter and some good pumps. Unhook the fuel inlet to the fuel dist and flush out the fuel lines before even trying to start it. Look inside the fuel inlet at the fuel dist. There is (or should be) a screen inside the dist that can be plugged up. Clean it. Don't just get the pump problem fixed and then try to start it. If you get trash in the fuel dist the cost of repair will go up a lot. I have never been able to clean a dist and get it to work again.

Good luck. If you have any questions to someone that has been there, let me know. Is the car worth fixing?

Paul