This Mercedes normally runs on benzine. It has a 4520 cc motor.
Now, this vehicle does not catch after trying to start.
I measured the current drawn by the fuel pump: More than 10A at 12V from an external power supply.
Question : Is this normal ? The pump clicks, but I cannot hear it running.
Who can help with hints ?
How to repair this car ?
Thanks in advance.
W.V.
They certainly aren't silent when in operation, this one of yours is seized, time for a new one.
Hello
The engine is equiped with a D-jetronic FI. Early D-Jetronic fuelpumps usually run with 6-8 amps at 13 Volt. So 10 amps doesn´t seem alarming especially if the pump still works ( Those pumps are a bit expensive today ). Also the currency draw was messured without runing engine wich will add some load due the "backpressure" in the system.
Now the get on with your problem first thing to check would be the condition from the fueltank. Rust is a know problem and sticks up your filters.
Next step is to messure the fuelpressure on the rail and messure if the fuelpump delivers enough quantity ( You can skip that as the engines usually work with pumps below specs in normal temperature zones )
If that show up correct we have to move to troubleshoot EFI and ignition.
First step would be to remove a easy accesible spark plug after a start attempt. If the sparkplug is wet we either have no spark or to much fuel. If the sparkplug is dry we have no fuel.
If you have wet sparkplugs the best is to renew them. But previously you must check the ignition for problems if not you might drown the new plugs again.
I recomend NGK over Bosch as they seem to work better under wet conditions ;)
Grüssle
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