SeaCoupe

Okay, I want to make sure my fuel pump is out before I go throwing money at parts. Can I get a confirmation....

When you put the key to the run position, do you hear your fuel pump from the rear of the car? Please insure you are not mistaking the throttle and S/C divert valve action.

Thanks for a fast response.

Ed

XsuperbeeX

run position = 1st turn right? if it is... maybe... I always hear a hissing sound

SeaCoupe

Run is the position the key goes to after you hit the starter.

So key goes in- turn clockwise to accessories, then run, then turn on....reverts back to run.

johnand

Ed,

I am really sensitive to noises in the car (Like Glyn), but I have NEVER heard my fuel pump. I should try and sit in the back seat and have my wife turn on the ignition and see if I can hear it.

LILBENZ230

I hear a constant buzzing sound on my C230K in that position.

SeaCoupe

John,

I think I started hearing it after I did my first fuel filter change. I just got in tune with it. So, when I didn't hear it, I kind of had a guide on where to start. Issue is that I don't want to start throwing money at parts that don't need to be changed. So, I need to get a drivers and passenger pump?

C230 Sport Coup

Ed, I usually can hear the fuel pump.
Best way to find out, is get a pressure gauge.
Is your car dead?

Glyn M Ruck

+1 - Ed - you only have & only need one pump. The other unit under the back seat round ports is just the other level sender unit.

SeaCoupe

So just confirming, the fuel pump is on the Drivers side? I have the cover off and see all the lines etc. So the sending unit is on the passenger side?

I'll order the part and get cracking.

Ed

johnand

WIS document I posted in your other thread says "right" (passenger?) side. Since you said you see the fuel lines on the drivers side one, I would say that is it. Hopefully someone that has physically changed it can chime in.

Glyn M Ruck

John & Ed. I have done this job & most SA cars have the pump on our drivers side - i.e. your passenger side.

Due to SA experience I misled ChrisBrown when we sorted his pump. It would appear that most US cars have the pump on the Drivers side rear. It seems this is not consistent. Both sides have senders & pipes.

This is how I expect yours to be - pump side = 120
]

splinter

#110 contains the pump proper.
Can unequivocally state at least some U.S. variants have their fuel pump fitted to the starboard side of the tank.

Had a failed pump, sender and rear SAM replaced recently. Don’t know which one ultimately precipitated the hapless chain of events, but my billfold was lightened to the tune of $2000 - mostly owing to its superseded AMG-specific goodies. Momentarily contemplated sending it downstream for a sensible Accord or Camry. Got over that mindset pretty quickly upon driving it once again...accounting department notwithstanding.
Coupé, late-model, and filter-in-tank members’ experiences may well differ. YMMV

SeaCoupe- trust you’ll take note of your four- or five-pin wiring connections when ordering appropriate replacement hardware.

Glyn M Ruck

OK there we have another example of things the other way round like I'm used to. You will find a thread somewhere cursing me & the Install University write up for misleading people that this is normal. Seems we have a lack of consistency in this. I have not established any MY correlation. Ed just check both sides starting with passenger then. It's very obvious which sensor contains the pump. I'm sorry if I have further muddied the water but after being criticised previously I had deduced that most US cars where different to SA cars built here.

Thanks - splinter!

Ed - the Install University write up should serve you well in that case.

johnand

Geez, looking at the WIS documents for fuel pumps, sending units, the tank rings, etc, just made me more confused. Why couldn't MB be consistent on which side the damn fuel pump is one

Splinter is right, and EPC shows the pump as #110. Glyn is right and there are fuel lines to both senders too according to WIS, so you can't use that to determine.

Good luck Ed. Let us know how it goes.

Glyn M Ruck

Yes - my bad - I used the #120 to indicate location NOT part. I will be more precise in future.

Indeed the EPC for SA models shows #110 to be pump containing sensor.

splinter

Did you get it squared away?

ISLAND03Z

Got a question for someone. I found this picture from google trying to find the answer. I've been installing the fuel pump on my c230 and there is an arrow on the lid that holds the fuel pump down. I didn't notice it when I took it apart but can someone tell me which direction the arrow is supposed to point?

I put the car back together and the most logical way to put the fuel pump in had the arrow pointing out the passenger side door but i've seen arrows before while doing other car maintenence and it's always pointed to the front of the car. Anyone know?

Glyn M Ruck

C230 Sport Coup

Geez Glyn, almost 15K posts in 4 years.