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  #1  
Old 01-19-2003, 04:50 PM
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Location: Kingsport, TN
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oh no, fuel pump nr.2 leaks, too

Hi everybody,
I thought I had it all under control. This morning I went under the car again to see if I should replace any other parts/hoses besides the fuel filter and the copper sealing rings. Started it just to see that it was still not leaking, but it leaked again. This time it comes from pump 2 and it seems to come right from the terminal. I took the connector off to see better but nothing to see. Pump 1 is still ok.

1. If it comes throught the terminal, does that mean the pump needs to be replaced?
Was "rudy" correct, after all?
My fortune cookie today said: Face facts with dignity.

2. If I have to replace the pumps, should I replace the check valves, the fuel storage unit, the tubing and the hoses that tie it all together? The tubing doesn't really look too good to me.

3. Is it difficult to replace the 2 hoses that connect to the tank or can you just screw them in and out? (It looks like that).

4. Is the "fuel storage unit" in the CD identical with "fuel accumulator" for $87.48 at Fastlane ($136.00 list)? Doesn't look like it could cost that much.

5. Anything that I should know before attempting to replace everything like tools etc.? I know fuel will come out and I will have to deal with that.

Right now I feel like I should clamp the hose that comes from the tank and the one that goes to the engine and disconnect from these two hoses. Then the whole unit should come out after loosening 2 screws on a bracket to the floor. Put it on the kitchen table and use as model to rebuild out of new parts. Then back under the car and mount new unit.

Your knowledge/advise is very much appreciated.
Reinhard Kreutzer

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oh no, fuel pump nr.2 leaks, too-leaky-terminal-2.jpg  
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  #2  
Old 01-19-2003, 09:24 PM
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You did not mention what model...

but, you should change all the hoses that "don't look good" while you are there. Caution, some new hoses are different than the old ones. In other words, if you change one, you may have to change others as well. Yes, they just screw in and out. Check with your parts department.
Check valves are not expensive and they should be changed. As far as the fuel accumulator (it is expensive), if the car is not giving you problems, you may skip that item but change the fuel filter if it has not been done recently.
Common tools would work. Disconnect the battery for extra precaution and work on a ventilated area.
In your picture is not clear (to me) where the fuel is leaking from. Can you be more specific? Is it possible that may be leaking from somewhere else and going down the wire to the terminal?
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  #3  
Old 01-19-2003, 10:48 PM
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Thanks, J.HIDALGO
I could'nt get a good picture but it is leaking right out of that blue terminal. The banjo bolts were dry. Yesterday, the first pump leaked right out between the check valve and the banjo fitting. This could prob. be rectified with new copper seals. I'm not sure whether the tightening of the first put more pressure on the second pump but I figure if I replace only one pump the other one will go pretty soon. After all, they look like originals to me, while the filter looks more recent.
I am just concerned that the fittings into the tank might give me trouble.
This is how the hoses look from behind.
Thanks again.
Reinhard Kreutzer
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oh no, fuel pump nr.2 leaks, too-inner-side-pumps-2.jpg  
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  #4  
Old 01-19-2003, 10:50 PM
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And this is where they go into the tank
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oh no, fuel pump nr.2 leaks, too-hoses-into-tank-2.jpg  
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  #5  
Old 01-19-2003, 11:40 PM
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I had a leak from the fuel filter(103 motor) once after changing it and it simply was a matter of tightening up the connections. I did install new washers. Are you sure all connections are good and snug? I suspect the pump may also leak if things aren't snug.
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  #6  
Old 01-20-2003, 02:08 AM
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When I worked on mine...

I removed the whole unit and worked on it on the bench. Then I re-installed the whole unit. Obviously, you can not do that with some of the hoses/parts.
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Old 01-20-2003, 08:53 AM
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Thanks Mike Richard and J.HIDALGO,
but I'm pretty sure it comes from that terminal. The picture doesn't show it but the fuel was running right down that wire and once I removed the connector it looked like it was coming from around the threaded stud. Tightening up worked as a temporary means on pump 1 (see different thread).
How do pumps normally go, just stop to pump, or do they leak somewhere?

By looking at the picture now, I wonder whether that threaded stub can be tightened? Anybody know? I might take another look at it before ordering all the parts.

Thanks for your help.
Reinhard Kreutzer
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  #8  
Old 01-20-2003, 01:45 PM
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Well, I got under the car again and the fuel is definitely coming from that terminal. It is just difficult to take a picture with the drop clearly showing. It is just developing on this picture.
I tried to tighten the threaded stud more but it feels like it might be overtightened already. Is that a weak point on this pump and do you have to be careful of not overtightening it? They only hold the wires so there is no need to really tighten them.

I forgot to mention that this is a 1987 420 SEL, so the pumps, hoses etc. will be 15 years old.

Thanks again for your help.
Reinhard Kreutzer
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oh no, fuel pump nr.2 leaks, too-drop-terminal.jpg  
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  #9  
Old 01-20-2003, 02:23 PM
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A word of caution here!! Do not touch that wire to ground with the ignition on. I can tell you from experience that you will kill the fuel pump relay!!! I accidentally let mine touch that metal fuel line and and ZAP!!! it was all over!!
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  #10  
Old 01-20-2003, 02:42 PM
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Thanks Stephen,
I hope its not too late.
I put it back on the terminal and put the rubber boot back over it. There is not much I can do until I get the parts except try to get as much fuel out from the tank via syphoning. I try to memorize how it all fits together.

What are the signs of a burnt fuel pump relay?

Thank you
Reinhard Kreutzer
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  #11  
Old 01-20-2003, 03:35 PM
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The fuel pumps won't run.
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  #12  
Old 01-20-2003, 04:22 PM
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Thanks again, Stephen,
Car started as usual when I drove it off the ramp and it is still leaking about 1 drop every 2-3 seconds. Maybe I got lucky this time. (It could be running on the fuel already pumped to the front...I didn't run it very long.)
I know the procedure starts with disconnecting the battery. I will certainly do that when I attempt to take it apart.
Regards
Reinhard Kreutzer
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  #13  
Old 01-21-2003, 04:56 PM
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Fried fuel pump relay

If you do fry your relay, remove it and short terminals 7 & 8 - that will make the pump run (but you will lose the rev limiter built in to the relay) and at least get you mobile. Just remember to pull the shorting wire when you leave the car.

If you short using an ammeter across 7 and 8, you can read the current consumed by the pumps - my 560SEL (1990) with one pump consumes 8 amps, which is correct. Two pumps should consume 15 amps. Anything much higher and you may have a pump ready to go out.
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  #14  
Old 01-21-2003, 06:57 PM
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Thanks Thomaspin,
that is good to know. A mechanic some time ago gave me a shorting wire for the heat sensor that runs the fan. If the engine runs hot this would run the fan at full speed and you get the most cooling. I have that piece of wire in the glovebox. See whether it fits there, too.
I will also test the current my fuel pumps use. One is leaking at the blue terminal and there is probably not much else but to replace. The other is just as old but that test might reveal more precise it's condition. I assume the relais is somewhere near the fusebox?
Thanks again for your help.
Reinhard Kreutzer
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  #15  
Old 01-21-2003, 07:24 PM
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Location: Visalia, CA
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Not that its all that related, but the wife and I are shopping for a digital camera, and the mechanic-by-day/photographer-by-night that I work with is impressed with your photos. May I ask what it was that you used? For the record, we have a small sony here at the shop we use to photograph evidence/damage/what it looked like before we took it apart photos, but its no where near as good as your images. Thanks.
MV

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