Author Topic: Fuel Pump?  (Read 1003 times)

acbrock

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Fuel Pump?
« on: May 13, 2024, 19:55:15 »
Ok, odd question.  So... I have been having some issues with the car not turning off when I turn it off.  It just keep running.  So someone mentioned I just just pull the #4 Fuse to the fuel pump and it will starve itself.

So I did that once.  Then I tried again and it did not turn the car off.  Odd.
So I pulled the fuse yesterday.  Today I needed to move the car, so I started it up and drove it around for about 5-10 minutes then parked it.  It would not turn off again.  I kept turning the key and it finally stopped when I turned it to the right.  Is made a screeching sound and stopped.

I was about to get back to some electrical testing and popped the Hood.  I saw that the Fuel Pump Fuse was still not IN.  I never put it back in.  It was just sitting there.  Is that possible the car could run without a fuel pump?  Or do I have some crazy other issue going on now.


1966 230SL Automatic 717G Papyrus White "Minny"

acbrock

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Re: Fuel Pump?
« Reply #1 on: May 13, 2024, 20:34:12 »
Hmm I guess reading around the internet sounds like I can run without the fuel pump?  Just won't run well?  And I will say it was the worst drive I have had in the car in a long time.  I thought maybe it was just really cold.
1966 230SL Automatic 717G Papyrus White "Minny"

Kevkeller

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Re: Fuel Pump?
« Reply #2 on: May 13, 2024, 22:26:34 »
My fuel pump seized one time and melted the plastic on the rotor. The fuse (correct amperage) never blew. The engine still ran.

I think the fuel injection pump has the ability to suck fuel but you don’t want to do that for several reasons.

If the engine doesn’t shut off when you remove the key then either the power to the  ignition and distributor is not being removed or you have enough carbon build up in the cylinder heads that is igniting the fuel mixture.

I would pull off the small wire on the side of the distributor and if the engine doesn’t stop you probably have carbon build up.  You can spray water into the air intake and you will steam clean the cylinders.

1970 280 SL

roymil

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Re: Fuel Pump?
« Reply #3 on: May 13, 2024, 22:33:57 »
Is it possible you have a bad ignition switch?
Mark Miller
1968 280SL
Rode in his pagoda's first mile.

acbrock

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Re: Fuel Pump?
« Reply #4 on: May 13, 2024, 22:48:49 »
Cool I will try those tests.  The ignition is 1 part I never touched on this car because to take it out I would have to drill it out.  So hopefully it has not suddenly failed.  I popped up with all these electrical issues I am having so I hope it all works itself out when I start getting other things fixed.
1966 230SL Automatic 717G Papyrus White "Minny"

Cees Klumper

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Re: Fuel Pump?
« Reply #5 on: May 13, 2024, 23:01:31 »
Ignition should not require to be drilled out I would think/hope! Just removing one small wire from the coil should do it. Carbon build up should manifest itself by a very unsteady idle, bucking etc and should not continue for a long time, I would think.

You know, I am in Santa Monica every Tuesday and if it would help, can swing by on my lunch break one of these weeks? 'A picture paints a thousand words' after all, I just may be able to give you some pointers after my 25 or so years of Pagoda ownership and my general mechanical experience with older cars. Just let me know.
Cees Klumper
1969 Mercedes 280 SL automatic
1968 Ford Mustang 302 V8
1961 Alfa Romeo Giulietta Sprint Coupe 1600
1962 FIAT 1500S OSCA convertible
1972 Lancia Fulvia Coupe 1.3
1983 Porsche 944 2.5
1990 Ford Bronco II

acbrock

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Re: Fuel Pump?
« Reply #6 on: May 13, 2024, 23:44:53 »
Wow what a nice offer!   If I cannot figure this out I might take you up on that!

Last summer when I started this I was trying to get the ignition out so I could clean it up.  Maybe it was just the chrome front but after digging thru this forum I found some posts that said there are 2 screws that need to be taken out to get it out.  But for a couple years they just used pins that needed to be drilled out.   So I got a camera in there and the little holes I had did not have screws.   But interesting.  Maybe the entire ignition could come out in a bigger piece with the chrome attached.  I will dig into my videos and see what is there.   I took everything out of the dash except the ignition and steering I did not touch… oh and the wire harness.
1966 230SL Automatic 717G Papyrus White "Minny"

acbrock

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Re: Fuel Pump?
« Reply #7 on: May 13, 2024, 23:47:09 »
Haha as I hit post on the last one I realized something funny.  Of those 3 things I did not touch 2 are now giving me grief!  Hope I don’t lose my steering next.   Maybe those pieces are jealous they did not get the deep clean bath and get to live inside for a few months. 
1966 230SL Automatic 717G Papyrus White "Minny"