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> Fuel pump just quit
surfdogskier
post Oct 26 2019, 11:51 AM
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So I had everything working well on my carb conversion with the exception of the fuel pump which constantly ran unless I pulled the ground wire per SirAndys carb conversion write up.

Now my pump will not work at all. I direct wired it to the battery to see if the pump was good and it worked. I connected a 12 volt wire to my relay board at the black/red wire #13 connection and it worked. So no issue with the wire. However something on the relay board or relay prevents it from working when the key is turned on.

I was going to wire it to the 2 other points on the relay board to get 12 volts (T4b and the #12 pin on the T12 connector). However, with the key turned on, I am not getting 12 volts to either of these. the T4b, I am getting 2 volts and the pin 12 on the T12 I am getting 4 volts.

My only other option to get 12 volt power is to connect to my coil but I have read this is not a good idea.

Looking for some guidance.


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lierofox
post Oct 28 2019, 01:17 PM
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The biggest point of caution I'd give for that solution:

Your fuel pump is now no longer fed by a relay, and the wires coming from the key switch to feed the relay board might cause problems as a result, both from the long path and the fact that they're powering the pump directly instead of switching a small relay coil, depending on the fuel pump you're using that could be between 5-15 amps.

The wire for your fuel pump is also no longer fuse protected, where previously it was protected by the 25a fuse, now there's just a wire going directly from the battery, forward to the ignition switch, over to the un-fused side of the fuse panel, back to the rear again, and finally back to the fuel pump.
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surfdogskier
post Oct 28 2019, 01:55 PM
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QUOTE(lierofox @ Oct 28 2019, 03:17 PM) *

The biggest point of caution I'd give for that solution:

Your fuel pump is now no longer fed by a relay, and the wires coming from the key switch to feed the relay board might cause problems as a result, both from the long path and the fact that they're powering the pump directly instead of switching a small relay coil, depending on the fuel pump you're using that could be between 5-15 amps.

The wire for your fuel pump is also no longer fuse protected, where previously it was protected by the 25a fuse, now there's just a wire going directly from the battery, forward to the ignition switch, over to the un-fused side of the fuse panel, back to the rear again, and finally back to the fuel pump.

I thought about that fuse issue. It was a concern. I am going to add a inline fuse in that wire. I just wanted to make sure it would run well first then do it.
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Posts in this topic
surfdogskier   Fuel pump just quit   Oct 26 2019, 11:51 AM
rhodyguy   With the key in the on position, do you have 12v a...   Oct 26 2019, 12:03 PM
surfdogskier   With the key in the on position, do you have 12v ...   Oct 26 2019, 12:31 PM
lierofox   So I had everything working well on my carb conve...   Oct 26 2019, 12:32 PM
surfdogskier   So I had everything working well on my carb conv...   Oct 26 2019, 12:33 PM
surfdogskier   I am not seeing any blown fuses under the dash or ...   Oct 26 2019, 12:44 PM
rhodyguy   the last sentence has me confused. The stand alone...   Oct 26 2019, 12:57 PM
surfdogskier   the last sentence has me confused. The stand alon...   Oct 26 2019, 01:03 PM
lierofox   [quote name='rhodyguy' post='2757415' date='Oct 2...   Oct 26 2019, 02:33 PM
surfdogskier   [quote name='rhodyguy' post='2757415' date='Oct ...   Oct 26 2019, 04:57 PM
lierofox   Thanks for this image and info. I haven't se...   Oct 26 2019, 05:18 PM
Minerva's 914   RE: Fuel pump just quit   Oct 26 2019, 01:11 PM
Superhawk996   :rotfl: Well done!   Oct 26 2019, 04:17 PM
rhodyguy   with the extra wire for power and the jumper groun...   Oct 26 2019, 01:46 PM
surfdogskier   with the extra wire for power and the jumper grou...   Oct 26 2019, 02:14 PM
porschetub   Did you check the pump and power supply relays,rea...   Oct 26 2019, 03:22 PM
rhodyguy   Are you sure the relay is good? Plug it in to a re...   Oct 26 2019, 03:26 PM
injunmort   I would suggest getting rid all jumpers, grounds a...   Oct 26 2019, 03:36 PM
surfdogskier   I swapped the relays around but there was no diffe...   Oct 26 2019, 04:00 PM
lierofox   I swapped the relays around but there was no diff...   Oct 26 2019, 04:38 PM
porschetub   I swapped the relays around but there was no dif...   Oct 26 2019, 11:40 PM
surfdogskier   She now purrs like a kitten. Thank all of you fo...   Oct 27 2019, 06:07 AM
KELTY360   She now purrs like a kitten. Thank all of you f...   Oct 27 2019, 02:34 PM
surfdogskier   She now purrs like a kitten. Thank all of you ...   Oct 27 2019, 06:42 PM
lierofox   The biggest point of caution I'd give for that...   Oct 28 2019, 01:17 PM
surfdogskier   The biggest point of caution I'd give for tha...   Oct 28 2019, 01:55 PM
914_teener   :thumbsup: :brain: :blowup:   Oct 28 2019, 01:46 PM
rhodyguy   :blink:   Oct 28 2019, 01:55 PM
Rand   I understand the hack to get by. I do that too. Bu...   Oct 28 2019, 04:09 PM
lierofox   I understand the hack to get by. I do that too. B...   Oct 28 2019, 06:30 PM


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