 1974 1.8 L-Jet afm issue |
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| engine247 |
 Oct 15 2022, 11:22 PM
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#1
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Newbie  Group: Members Posts: 9 Joined: 2-June 22 From: Austin Member No.: 26,590 Region Association: Southwest Region  |
Howdy. I have a new to me 1974 1.8 with the l-jet. Currently I'm sorting out some issues to get it running again. So the fuel pump comes on when the key is on. I realize this is not correct. I checked the afm and the contacts are basically closed at all times. The silver paper-clip arm that should be holding contact arm open isn't doing it. It is like there is not quite enough tension to bring the silver arm all the way back to open the contacts. The contact arm itself appears pretty straight if that matters. The fuel pump does act correctly if the afm is unplugged or the contact is manually opened.
Any ideas on the proper way to address this issue? or have a good reference that I just haven't found yet? many thanks for any info |
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| L-Jet914 |
Oct 15 2022, 11:41 PM
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#2
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Member Group: Members Posts: 237 Joined: 24-October 12 From: Davis, CA Member No.: 15,080 Region Association: Northern California |
The arm that contacts the fuel pump contacts can be adjusted by lightly bending it so it does not contact the fuel pump contacts. Someone had done the same thing to my 74 1.8L AFM to alleviate the vapor lock issue, so when the key was turned on the fuel pump always ran. On the L-Jet engines, the fuel pump is only supposed to run when the engine is cranking and the flap gets moved and contacts the fuel pump contacts. You have to be very gentle adjusting the arm and it will push the contact arm away from the closed position. Bend A until it opens the fuel pump contact C. You will have a very slight gap and when you turn the key on the pump will no longer run with key on. When you start the car, arm A moves away from C allowing C to close the contacts and energize the fuel pump. Do not touch B. @engine247 I do have a video of operation after I returned the arm back to it's factory position located on the 914World Facebook group page. It's the 2nd to last comment. https://m.facebook.com/groups/4020297998314...13750258659334/
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| Van B |
Oct 15 2022, 11:52 PM
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#3
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Senior Member Group: Members Posts: 1,583 Joined: 20-October 21 From: Maryland Member No.: 26,011 Region Association: None 
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Does your AFM look like this? (Engine is idling here)
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| Van B |
Oct 15 2022, 11:53 PM
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#4
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Senior Member Group: Members Posts: 1,583 Joined: 20-October 21 From: Maryland Member No.: 26,011 Region Association: None
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L-jet beat me to it lol…
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| L-Jet914 |
Oct 16 2022, 12:02 AM
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#5
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Member Group: Members Posts: 237 Joined: 24-October 12 From: Davis, CA Member No.: 15,080 Region Association: Northern California |
QUOTE(Van B @ Oct 15 2022, 10:53 PM)  L-jet beat me to it lol… (IMG:style_emoticons/default/laugh.gif) |
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| engine247 |
Oct 16 2022, 02:07 PM
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#6
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Newbie Group: Members Posts: 9 Joined: 2-June 22 From: Austin Member No.: 26,590 Region Association: Southwest Region |
Thanks L-Jet914. I didn't want to do anything detrimental. That corrected the fuel pump running. Now it's off to the next issue.
Cheers! |
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