fuel pump
 

Is it normal to hear the fuel pump humming when in the driver's seat, top up in a 380 SL. Or is the "humming" sound an indication of a faulty pump?

Thanks

I had the same sound (intermittently) for a few months before the fuel pump relay blew. In the interim, I replaced the fuel accumulator and the sound went away for a week - then the relay blew.

Frank

If you do this _now_ you may save that pump :

Remove it and run it backwards , pumping some clean Diesel fuel through it ~ the pumps get sediment in them and this is what causes them to die ~ lack of lubrication from proper fuel flow .

If you ever run the car out of fuel , the pump may well be ruined .

Failure to change fuel filters annually causes many pump failures too .

If it begins to squeak or howl , -immediately- drive it home or to shop as it's going to pack up shortly .

While there's talk of the fuel pump relay, can somebody tell me the location of the fuel pump relay on a 560SL and what if anything to do to gain access to it?

>>If you do this _now_ you may save that pump :

Remove it and run it backwards , pumping some clean Diesel fuel through it ~ the pumps get sediment in them and this is what causes them to die ~ lack of lubrication from proper fuel flow .<<

Ummm.... 380SLs and 560SLs ain't got no diesel engines.:silly:

Frank

fuel pump backwards?
 

Thanks . This is a gasoline pump not a diesel pump. Your advice to run some diesel fuel through backwards still okay if its a gas pump? Also when you say run backwards , is this manual or powered? IF POWERED HOW DO i DO THIS?

Thanks for all the comments

The fuel pump relay on a 560SL is behind the glovebox. There are three relays back there. One, I believe is for the AC. I think the fuel pump relay is behind the other two (naturally) and is much harder to get at.

Thanks for the info maheath.:cool:

FWIW; Just replaced the fuel pump in a Chevy S-10- $275 for the pump please. Parts man told me I was lucky it wasn't a v-6, they are $400. Anyway, from what I deduced, the failure was caused by a grossly plugged fuel filter. The filter had not been change in the life of the truck-145k miles, and I think that it was the strain of pumping against a plugged filter that caused the failure.

Might be sure that the pump is not overpressuring against some blockage in the line.

The pump in a GMC Sanoma is $400+ too. I lost that one and one in a Dodge Grand Caravan because of fuel filters.