450SL 107 fuel pump

Isdyldan

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'71 350 SL, Mercedes 350 CLS SB, '94 Shogun 2.8 LWB, '73 Porsche 914
Hi - I've been trying to get my '72 450SL started for a while now, and was wondering if someone could help please. I am trying to rule out a fuel pump or solenoid fault by disconnecting the fuel line where it joins the rail in the engine bay. I was expecting to see fuel when the ignition is switched on to pressurise the rail, but nothing comes out, even when cranked. I do hear a short 'buzz' from the pump when the ignition is turned on - is this correct please? Should fuel be pumping with the ignition on please?
 

television

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The fuel pump does run for a few seconds when you turn on the ignition. the pump package is under the rear of the off side wing

http://www.detali.ru/cat/oem_mb2.as...&L=765.701&CT=F&cat=048&SID=47&SGR=030&SGN=02


The fuel pump relay controls the fuel pumps,,the pulses are taken from the crankshaft sensor, if no pules within a few secs,it cuts. you can by pass the relay by removing it and shorting out pins 7 and 8
 
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Isdyldan

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'71 350 SL, Mercedes 350 CLS SB, '94 Shogun 2.8 LWB, '73 Porsche 914
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Ok, thanks Malcolm. I've found the pump - where is the relay please? If I short out those pins, will the pump run continuously when the ignition is on?
Thanks, Dylan
 

television

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Its a hard question where is it,,I think under the dash,but not 100% when it is shorted out it will run all of the time
 

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