1972 Mercedes 280SE V8 - No fire, suggestions?

[BenzGmarket]

Hello,
I have this 1972 Mercedes 280SE that is not getting fire to the fuel pump or fire at the plugs. It will run when I hot wire is ran directly to the fuel pump.  Any ideas?

[Big_Richard]

I just realised thats not a w116 so I've no idea.


Does that era car use a fuel pump realy ? check it, and what ever is supposed to power that relay and trace the wiring back from there.

[oscar]

Is it a 3.5L or 4.5L? I just realised you said it was a V8 so I'm assuming it's a w108 with a V8.

Anyway, I agree with the Major.  Check the fuel pump relay. 

[13B]

Oscar,

If the fuel pump relay is failed would putting a small amount of petrol down the intake and giving it a crank cause a momentary blurt into life?

I.

[oscar]

Yes.  I can't see how a faulty relay would affect the ignition at all so it should fire.  Haven't tried it myself but there's been a few others try that.