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> Fuel Pump will not run, Checked fuse, relay, etc
BCinSC
post May 29 2011, 08:42 AM
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So Blanche ('73 White 914-4 1.7L) was running great last summer until she simply stopped on I-95 in Burlington, MA. Simply no spark anymore. Having no time to deal with it, she sat until today. I figured out the spark problem, but now the fuel pump, won't. Familiar with this type of issue, I open the relay board and check the fuse and the relay. I've got 12V where I'm suppose to - both sides of fuse, pin85 of FP relay when key on (FI Brain energizes to close circuit to join pin30 and pin87 I believe). PIN13 of connector closest to firewall, which diagram says goes out to FP itself, shows continuity to ground, so I'm guessing broken wire somewhere. Sounds reasonable/plausible? Fuel Pump was functional before I put her away.
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SLITS
post May 29 2011, 09:05 AM
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Pumps do gum up or fail.

Run hot wire to + terminal and another to ground and see if the pump will run at all as a test. If it does, go from there with the tracing of wires.
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BCinSC
post May 29 2011, 09:12 AM
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Is that Gumby with a Blunt? Anyway, I think you are correct that the pump has failed. It has continuity through it and I don't think it should. Another one I have that I believe is good, does not have continuity. I will check both as you suggest.
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Tom
post May 29 2011, 09:12 AM
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Bruce,
Just went thru this yesterday with another member.
1- with the fuel pump relay removed, jump pin 13 and 14 of the 14 pin connector. Pin 14 is always hot, so you don't need the key on. If the pump runs, the pump and wiring are good, and the problem is in the relay board somewhere - most likely ( I can never be 100% sure with these cars). If pump does not run, check with voltmeter to ensure 12 Volts at pin 14. This comes from the batt +, one of the 4 large red wires attached at the batt. If the voltage is present, then you have a wiring or fuel pump problem.
Let me know what you find and we can go from there to find the problem.
Tom
PS; you will continuity thru the pump brushes to ground, don't let that throw ya.
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Elliot Cannon
post May 29 2011, 09:13 AM
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QUOTE(SLITS @ May 29 2011, 08:05 AM) *

Pumps do gum up or fail.

Run hot wire to + terminal and another to ground and see if the pump will run at all as a test. If it does, go from there with the tracing of wires.


I agree with Ron? (IMG:style_emoticons/default/agree.gif) I had the same problem with the Zonker. Twice!! Hot wired a spare battery to the pump and it DIDN'T run. Very quick trouble shooting. (I guess the old geezer DOES know what he's talking about). (IMG:style_emoticons/default/lol-2.gif)
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SLITS
post May 29 2011, 09:37 AM
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QUOTE(Elliot Cannon @ May 29 2011, 08:13 AM) *

QUOTE(SLITS @ May 29 2011, 08:05 AM) *

Pumps do gum up or fail.

Run hot wire to + terminal and another to ground and see if the pump will run at all as a test. If it does, go from there with the tracing of wires.


I agree with Ron? (IMG:style_emoticons/default/agree.gif) I had the same problem with the Zonker. Twice!! Hot wired a spare battery to the pump and it DIDN'T run. Very quick trouble shooting. (I guess the old geezer DOES know what he's talking about). (IMG:style_emoticons/default/lol-2.gif)


I do have my "senior" moments, especially with a blunt. (IMG:style_emoticons/default/confused24.gif)
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BCinSC
post May 29 2011, 10:11 AM
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Argh. Swapped pumps and same deal. Could FI Brain be disabling somehow? Wiring seems good and both pumps function while connected directly to 12V. Jumping 13 and 14 as you suggest DOES run pump (but I shouldn't let it for more than a couple seconds, right?)
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SLITS
post May 29 2011, 10:16 AM
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QUOTE(BCinSC @ May 29 2011, 09:11 AM) *

Argh. Swapped pumps and same deal. Could FI Brain be disabling somehow? Wiring seems good and both pumps function while connected directly to 12V. Jumping 13 and 14 as you suggest DOES run pump (but I shouldn't let it for more than a couple seconds, right?)



As long as you have fuel flowing thru the system, you can run it as long as you want. Fuel cools the motor on the pump. Dry .... not so good as it will overheat and kill the pump.
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BCinSC
post May 29 2011, 10:26 AM
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I don't get it. I have 12V at Pin30 of Relay. I have continuity from Relay Pin87 socket to harness PIN13. I can run the pump jumping harness 13 and 14. I have checked the relays and swapped with spares. What am I missing?
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BCinSC
post May 29 2011, 10:34 AM
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Mess with it long enough, and miraculously, it will work. Pump now functional (not exactly sure why, but not complaining). So now I have crank and gas, how does one person check that spark it working?
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Tom
post May 29 2011, 10:51 AM
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The relays sometimes don't fit tight in the socket. The pins can be spread slightly to get a better fit. Sounds like you had an intermittent relay connection.
As for spark, pull one plug wire and put an old plug or screwdriver in the plug wire. Hold the spark plug to ground or screwdriver close to ground and crank. You should see a spark from the spark plug or from screwdriver to ground.
Tom
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BCinSC
post May 29 2011, 12:09 PM
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Not quite the contortionist I used to be. Can't seem to manage turning key to crank and holding plug lead to screwdriver to ground point all at same time. Did hookup strobe and don't see it flicker, so maybe that's something?
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BCinSC
post May 29 2011, 12:17 PM
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Hooked up known good spark plug to wire #1 and cranked. No spark. Back to square one. Suggestions?
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benalishhero
post May 29 2011, 01:03 PM
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No spark? Are you running points and condensor?
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BCinSC
post May 29 2011, 01:34 PM
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Yes. Both relatively new (couple thousand miles at most). Checked the points, which appear to be functioning correctly (at least they open and close as crank turns)
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BCinSC
post May 29 2011, 01:36 PM
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I reiterate that I was doing 60+ on the highway when she died. Tach just went to zero and no more power. Coasted to shoulder, where she would crank, but not catch. Same today.
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Elliot Cannon
post May 29 2011, 01:38 PM
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QUOTE(SLITS @ May 29 2011, 08:37 AM) *

QUOTE(Elliot Cannon @ May 29 2011, 08:13 AM) *

QUOTE(SLITS @ May 29 2011, 08:05 AM) *

Pumps do gum up or fail.

Run hot wire to + terminal and another to ground and see if the pump will run at all as a test. If it does, go from there with the tracing of wires.


I agree with Ron? (IMG:style_emoticons/default/agree.gif) I had the same problem with the Zonker. Twice!! Hot wired a spare battery to the pump and it DIDN'T run. Very quick trouble shooting. (I guess the old geezer DOES know what he's talking about). (IMG:style_emoticons/default/lol-2.gif)


I do have my "senior" moments, especially with a blunt. (IMG:style_emoticons/default/confused24.gif)


Gosh!! What's a blunt?
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Elliot Cannon
post May 29 2011, 01:42 PM
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I just had a crap load of electrical problems with both cars and it turned out to be mostly corrosion. Roll up some sand paper, stick it down the holes for the relays and clean, clean, clean. It seems like I spend a lot of time looking for and controlling body rust and not enough time cleaning up electrical contact corrosion.
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BCinSC
post May 29 2011, 02:59 PM
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Checked points more closely and found that the metal (copper?) piece within the points arm that the dizzy pushes against was 98% broken and that the points really weren't separating at all. Fortunately, FLAPS should have in stock. Maybe she'll light up later today!
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djm914-6
post May 29 2011, 03:08 PM
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Sounds like you're having fun. WHo's watching the two kids, 8 dogs and the cat?
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