Bringing 280GE back to life
Hello from Canada!
I recently bought myself a 1987 280GE originally from Germany so LHD. It sat in someones field for the past 10 years so needs a bit of work. The fuel tanks are rusted petty bad and are out of the vehicle. I needed to replace the fuel pump, accumulator, fuel distributor, spark plugs, wires, filters, battery. I got it running using a fuel tank from a snow blower then it randomly stopped pumping fuel through the return line. it runs excellent if I pour fuel down the metering plate. Anyone have any idea why fuel will not pump through the return line anymore? Do you think it needs a pressurized tank to work? This sure is one heck of a complex fuel system. Any advice would be greatly appreciated. I am tired of replacing $200 parts on educated guesses.
Thanks
Sounds like your return line is blocked. After sitting for 10 years your G will need quite a bit of work. Mine had sat for about 10 years after the main drive shaft u/j broke & wrecked the powertrain. Don't worry about the $200 parts, its the $800-$1,500 parts that test your resolve. Disconnect both ends of the return line & blow compressed air and check for flow. Watch the crud blow out the other end! LOOK for any crimps in the return line. Reattach and test.
Also, listen for the fuel pump to pressurize when the ignition is turned on before starting the vehicle.
Anyways this is left to be done:
Pull the fuel tank(s) and steam clean, replace the control pressure regulator mounted to the engine, replace the injectors ($20 each), learn how to use a fuel pressure gauge & purchase the Bosch fuel injector book.
Also, there are several fascinating Youtube Bosch training videos. After mastering CIS injection, you can work on everything from Porsche's to Ferraris.
Stuart
You're testing my memory cells now but an educated (well that maybe an exaggeration!) guess would be:
The metering plate relies on fuel pressure to open/position itself at idle, you are by passing that when you open it with a screw driver. As I assume you are starting the vehicle from cold I would suspect the cold start valve. Failing that I would guess fuel pressure. To figure that out you will need some test equipment.
When you first turn on the ignition you should hear a relay operate from the fuse box area and the fuel pump run for a few seconds and then stop. If it doesn't it will be the relay. These fail quite often and are pretty cheap. I can't remember the code for them but you'll find that online.
As stated above there are online resources for CIS. Once you know how it operates it's pretty simple and a great system. Unless you're lucky to find a mechanic who know the system you're better off figuring it out for yourself though.
You're testing my memory cells now but an educated (well that maybe an exaggeration!) guess would be:
The metering plate relies on fuel pressure to open/position itself at idle, you are by passing that when you open it with a screw driver. As I assume you are starting the vehicle from cold I would suspect the cold start valve. Failing that I would guess fuel pressure. To figure that out you will need some test equipment.
When you first turn on the ignition you should hear a relay operate from the fuse box area and the fuel pump run for a few seconds and then stop. If it doesn't it will be the relay. These fail quite often and are pretty cheap. I can't remember the code for them but you'll find that online.
As stated above there are online resources for CIS. Once you know how it operates it's pretty simple and a great system. Unless you're lucky to find a mechanic who know the system you're better off figuring it out for yourself though.
I will second all that, post or PM your chassis number and i can give you the Fuel Relay numbers etc
Gav
Thanks for the replies everyone. This fuel system has me confused. I think the no fuel going back to the tank was a minor leak off of the accumulator. Now... it still wont start on its own. If I prop the metering plate open with a screw driver it starts up really nice runs idles ect. If I hold it full open it will accelerate nice and stay running let off the gas dead again. Given all the parts i've replaced I'm pretty confused now. Recommendations as before are appreciated.