Help...I'm electrically stumped, Wait...that didn't sound right. |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Help...I'm electrically stumped, Wait...that didn't sound right. |
iankarr |
Apr 30 2016, 08:24 AM
Post
#1
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Hi Guys,
I posted earlier about my fuel pump not working. Before I went on a goose chase to find another, I thought i'd check the circuit (I may be learning from my mistakes after all). Anyway...I pulled the black and white leads off the fuel pump, hooked up my multimeter and turned the ignition switch to "on". Zero point zero. Moved around the relays on the board and no change. I assume those two leads are positive and negative and they should show 12V with the switch on, no? Any ideas? Thanks so much for your help. I SO want to get on the road this weekend... |
r_towle |
Apr 30 2016, 08:28 AM
Post
#2
|
Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
1)
Hook up 12 Vdc directly to the fuel pump, does it run? 2) can't help you from there without year, make, model, stock or not, carbs or FI... Rich |
iankarr |
Apr 30 2016, 08:30 AM
Post
#3
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Thanks man. Will check the pump directly. My car is a 73 2.0 (with a McMark-built 2056). Dual IDF 40 carbs.
|
McMark |
Apr 30 2016, 08:34 AM
Post
#4
|
914 Freak! Group: Retired Admin Posts: 20,179 Joined: 13-March 03 From: Grand Rapids, MI Member No.: 419 Region Association: None |
Fuel pump is wired with stock wiring? Do you have the ground from the relay board to trip the fuel pump relay on?
|
iankarr |
Apr 30 2016, 08:40 AM
Post
#5
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Just tested...the pump works when directly powered.
Mark...I believe it's stock wiring. Yes, the pin is grounded on the relay board. No change from the way it's been. What's weird is that the pump was working fine yesterday. All I did since then was disconnect and reconnect the battery (with the key off and out). Maybe a surge when the battery was reconnected? Is it possible that all the round relays blew? The wiring at the pump is one black and one white. Pic attached. Thanks so much for your help. |
JRust |
Apr 30 2016, 08:44 AM
Post
#6
|
914 Guru Group: Members Posts: 6,307 Joined: 10-January 03 From: Corvallis Oregon Member No.: 129 Region Association: Pacific Northwest |
For a temp solution you can run the power down from your coil. That will turn it on with your key still.
|
anderssj |
Apr 30 2016, 08:52 AM
Post
#7
|
Dog is my copilot... Group: Members Posts: 1,656 Joined: 28-January 03 From: VA Member No.: 207 Region Association: MidAtlantic Region |
Don't forget to check the fuse on the relay board--sometimes that fuse looks good, but corrosion on the tips means no current. A quick way to check is to see if the heater fan in the engine compartment comes on when the level on the cockpit floor is pulled up. If the fan doesn't come on, fuel pump won't either (at least on my '72).
Hope this helps! |
iankarr |
Apr 30 2016, 08:53 AM
Post
#8
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
You guys are like therapists...just talking to you helps solve problems.
FIXED. I did the headlight test on all the relays and found a bad one. Replaced it and voila...12V at the fuel pump. Thanks for helping my brain get into logical mode. That's not easy to do! |
timothy_nd28 |
Apr 30 2016, 08:55 AM
Post
#9
|
Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest |
Could be a faulty ignition switch. With the key at the "on" position, try nudging the key in this direction and sequence: up up, down down, left right, left right, B then A. Have the meter near by and see if it flinches as you move the key.
|
iankarr |
Apr 30 2016, 09:02 AM
Post
#10
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Many thanks, all!
|
r_towle |
Apr 30 2016, 11:30 AM
Post
#11
|
Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Cool, now go drive it!
|
iankarr |
Apr 30 2016, 10:40 PM
Post
#12
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Done! Took my first drive after a shit ton of winter work. So great. And I won a bet with my wife that the car would once again move under its own power. So I got that going for me. Which is nice.
|
ClayPerrine |
May 1 2016, 05:40 AM
Post
#13
|
Life's been good to me so far..... Group: Admin Posts: 15,469 Joined: 11-September 03 From: Hurst, TX. Member No.: 1,143 Region Association: NineFourteenerVille |
|
JOEPROPER |
May 1 2016, 06:29 AM
Post
#14
|
The answer is "no" unless you ask... Group: Members Posts: 1,184 Joined: 21-November 15 From: White Plains New York Member No.: 19,387 Region Association: North East States |
Good stuff cuddyk! When you get a chance, cruz that '73 over to White Plains so i can check out your progress. (IMG:style_emoticons/default/beerchug.gif)
|
Rob-O |
May 1 2016, 09:25 AM
Post
#15
|
Senior Member Group: Members Posts: 1,252 Joined: 5-December 03 From: Mansfield, TX Member No.: 1,419 Region Association: Southwest Region |
|
napasteve |
May 1 2016, 09:42 AM
Post
#16
|
914 driving winemaker Group: Members Posts: 504 Joined: 2-January 13 From: Napa, CA Member No.: 15,327 Region Association: Northern California |
Sounds like a Cinderella story
|
iankarr |
May 1 2016, 10:07 AM
Post
#17
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Done! Took my first drive after a shit ton of winter work. So great. And I won a bet with my wife that the car would once again move under its own power. So I got that going for me. Which is nice. Nice Caddyshack quote. Not sure many caught that. Gunga lagunga! (Or as my iCrap is trying to say...Hungary Laguna) |
r_towle |
May 1 2016, 03:18 PM
Post
#18
|
Custom Member Group: Members Posts: 24,574 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
|
iankarr |
May 1 2016, 10:27 PM
Post
#19
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Done! Took my first drive after a shit ton of winter work. So great. And I won a bet with my wife that the car would once again move under its own power. So I got that going for me. Which is nice. What was the bet? I mean, was it worth it? youll have to ask her if it was worth it (IMG:style_emoticons/default/smile.gif) |
iankarr |
May 1 2016, 10:31 PM
Post
#20
|
The wrencher formerly known as Cuddy_K Group: Members Posts: 2,473 Joined: 22-May 15 From: Heber City, UT Member No.: 18,749 Region Association: Intermountain Region |
Good stuff cuddyk! When you get a chance, cruz that '73 over to White Plains so i can check out your progress. (IMG:style_emoticons/default/beerchug.gif) Def! I just have to have my gray haired mechanic friend check my work first. I wrenched too many things that could strand me or worse. i usually get good grades, but this isn't my day job (IMG:style_emoticons/default/smile.gif) |
Lo-Fi Version | Time is now: 18th May 2024 - 04:24 PM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |