 Fuel pump relocation wiring question, the wiring is done I have a new question! |
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| scott_in_nh |
 Oct 14 2012, 08:56 AM
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#1
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Senior Member  Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States  |
So a couple of weeks ago I decided it was time to take care of a few projects on my 74 2.0 D-jet.
A PO moved the 3 port fuel pump up front under the steering rack, but never replaced the plastic fuel lines. The fuel pump works ok, but is noisy and doesn’t hold pressure when I shut the car off. The wiring for it was also cobbled – two wires were run through the tunnel and plugged into the original fuel pump plug, but apparently the positive wire failed so another wire was run from the relay board through the interior and to the pump. It was still grounded through the tunnel wire and original pump harness. I installed Tangerine SS fuel lines and replaced all other rubber lines I hadn’t already replaced and now I am installing a 2 port fuel pump and filter in the same location. The layout proved quite challenging, but I think I have a good solution. My question is can’t I just run the positive wire through the tunnel and ground the fuel pump in front? I did a search and some refer to running “wires” (plural) through the tunnel and some talk about running “a wire”. I just want to make sure I’m not overlooking something….. |
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Replies(1 - 19)
| SLITS |
Oct 14 2012, 09:10 AM
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#2
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"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None  |
Why not? The original ground point is the multi-ground under the relay plate. So pick up the positive from the harness (I ran it back thru the tunnel) and ground the pump where you have relocated it.
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| reharvey |
Oct 14 2012, 01:50 PM
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#3
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Senior Member Group: Members Posts: 573 Joined: 16-July 08 From: N. E. Ohio Member No.: 9,308 Region Association: North East States |
(IMG:style_emoticons/default/agree.gif) I've done it this way on five cars without a problem. Ray
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| SirAndy |
Oct 14 2012, 01:58 PM
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#4
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Resident German Group: Admin Posts: 41,657 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(scott_in_nh @ Oct 14 2012, 07:56 AM)  My question is can’t I just run the positive wire through the tunnel and ground the fuel pump in front? Doesn't the FI brain control the pump by controlling the GROUND??? In which case your pump would run all the time as soon as you turn on the key ... It's been a while since i dealt with the stock D-Jet, so i could be wrong on that. (IMG:style_emoticons/default/idea.gif) |
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| timothy_nd28 |
Oct 14 2012, 02:34 PM
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#5
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest 
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IMO, the fuel pump is too important to be not grounded correctly. I ran heavy gauge wire from the neg post of the battery to the fuel pump area. This wire was then grounded to the body near the fuel pump. Then I ran a small jumper from the new body ground to my fuel pump. It gives me peace of mind having a dedicated ground for my pump, yes it may be overkill.
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| Dave_Darling |
Oct 14 2012, 03:52 PM
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#6
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914 Idiot Group: Members Posts: 14,990 Joined: 9-January 03 From: Silicon Valley / Kailua-Kona Member No.: 121 Region Association: Northern California
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QUOTE(SirAndy @ Oct 14 2012, 12:58 PM) Doesn't the FI brain control the pump by controlling the GROUND??? Nope. The FI grounds a pin on the relay, which sends power to the pump or not. So it controls power to the pump, by controlling the ground to the relay. --DD |
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| SirAndy |
Oct 14 2012, 09:44 PM
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#7
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Resident German Group: Admin Posts: 41,657 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
QUOTE(Dave_Darling @ Oct 14 2012, 02:52 PM) QUOTE(SirAndy @ Oct 14 2012, 12:58 PM) Doesn't the FI brain control the pump by controlling the GROUND??? Nope. The FI grounds a pin on the relay, which sends power to the pump or not. So it controls power to the pump, by controlling the ground to the relay. Aha, i knew there was something about the brain and ground for the pump. Ground for the relay it is then, makes sense. (IMG:style_emoticons/default/beerchug.gif) |
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| scott_in_nh |
Oct 15 2012, 07:17 AM
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#8
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
QUOTE(SirAndy @ Oct 14 2012, 11:44 PM) QUOTE(Dave_Darling @ Oct 14 2012, 02:52 PM) QUOTE(SirAndy @ Oct 14 2012, 12:58 PM) Doesn't the FI brain control the pump by controlling the GROUND??? Nope. The FI grounds a pin on the relay, which sends power to the pump or not. So it controls power to the pump, by controlling the ground to the relay. Aha, i knew there was something about the brain and ground for the pump. Ground for the relay it is then, makes sense. (IMG:style_emoticons/default/beerchug.gif) Thanks for clearing that up! What a pain upgrading the fuel system has been! Tangerine's SS lines went in easy enough, but finding room for a 2 port pump and filter under the steeering rack AND getting it plumbed to the tank AND fixing poor work by PO's ended up being more difficult then drilling and welding the from swaybar mounts (my other project while the tank was out)... |
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| scott_in_nh |
Oct 15 2012, 05:46 PM
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#9
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
Getting closer - the new pump is in, wired and runs properly when the key is turned on.
I also test fitted the last two hoses, the ones that actually go to the tank. Attached thumbnail(s) 
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| scott_in_nh |
Oct 17 2012, 07:53 AM
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#10
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
So there are no gaskets (rubber washer?) between the pipes and the fuel tank (#11 and 13)
What are my options? The hardware store has rubber washers - what is compatible? Attached image(s) 
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| SLITS |
Oct 17 2012, 09:53 AM
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#11
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"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
There are fibre washers (fiber if you are Amerikan) .. whether they are available or not I can't say.
Part Numbers are: E 914 201 147 10 (#11) E 311 201 235 A (#13) Whether an aluminum or copper crush washer would work I won't address. If any flexible material was to be used, it should be Viton (Ethanol :puke: added fuels ya know). |
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| gothspeed |
Oct 17 2012, 10:40 AM
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#12
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
QUOTE(scott_in_nh @ Oct 14 2012, 07:56 AM) ....................................... I installed Tangerine SS fuel lines and replaced all other rubber lines I hadn’t already replaced and now I am installing a 2 port fuel pump and filter in the same location. The layout proved quite challenging, but I think I have a good solution. My question is can’t I just run the positive wire through the tunnel and ground the fuel pump in front? I did a search and some refer to running “wires” (plural) through the tunnel and some talk about running “a wire”. I just want to make sure I’m not overlooking something….. +1 .......... I am in the midst of doing this fuel pump 'wiring' myself ......... where or how did you get the wire past the engine firewall into the tunnel? Did you drill a new hole with a grommet? |
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| scott_in_nh |
Oct 17 2012, 11:02 AM
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#13
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
QUOTE(gothspeed @ Oct 17 2012, 12:40 PM) QUOTE(scott_in_nh @ Oct 14 2012, 07:56 AM) ....................................... I installed Tangerine SS fuel lines and replaced all other rubber lines I hadn’t already replaced and now I am installing a 2 port fuel pump and filter in the same location. The layout proved quite challenging, but I think I have a good solution. My question is can’t I just run the positive wire through the tunnel and ground the fuel pump in front? I did a search and some refer to running “wires” (plural) through the tunnel and some talk about running “a wire”. I just want to make sure I’m not overlooking something….. +1 .......... I am in the midst of doing this fuel pump 'wiring' myself ......... where or how did you get the wire past the engine firewall into the tunnel? Did you drill a new hole with a grommet? yes - that is exactly what I did! |
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| scott_in_nh |
Oct 17 2012, 11:02 AM
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#14
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
QUOTE(SLITS @ Oct 17 2012, 11:53 AM) There are fibre washers (fiber if you are Amerikan) .. whether they are available or not I can't say. Part Numbers are: E 914 201 147 10 (#11) E 311 201 235 A (#13) Whether an aluminum or copper crush washer would work I won't address. If any flexible material was to be used, it should be Viton (Ethanol :puke: added fuels ya know). viton it is - thanks |
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| Kraftwerk |
Oct 19 2012, 08:45 PM
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#15
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Member Group: Members Posts: 195 Joined: 6-September 07 From: Bbbbbrroooklynnn Member No.: 8,085 |
Hey Scott,
So how did it go? I might attempt the relocation pretty soon before it gets too cold here. What did you use for the washers at # 11 & #13? Did the tank just "lift out" or did you have to disconnect 11 & 13 first? thanks! |
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| Nozzle |
Oct 20 2012, 07:00 AM
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#16
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Member Group: Members Posts: 158 Joined: 6-November 08 From: Lexington Park, Maryland Member No.: 9,725 Region Association: MidAtlantic Region |
I'm in exactly the same situation, with a complete fuel system refurbish in process. Seems to be a common theme these days. At any rate this is the first time I've tried something like this and I'm using the standard AA fuel pump relocation kit for a stock '73 D-Jet. I have some questions based on replies to this thread:
Why not just run both ground and positive leads from the engine compartment to the steering rack area? The kit I got from AA supplies a combination wire to do this and I'm too much of an electrical novice to know why this isn't recommended here. Why are the copper crush washers for the supply and return that also came with the kit again not recommended? Thanks, John |
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| TheCabinetmaker |
Oct 20 2012, 07:09 AM
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#17
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I drive my car everyday Group: Members Posts: 8,300 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
the washers for the lines at the tank are available at the Bughaus.com.
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| scott_in_nh |
Oct 24 2012, 09:17 AM
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#18
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
QUOTE(Kraftwerk @ Oct 19 2012, 10:45 PM) Hey Scott, So how did it go? I might attempt the relocation pretty soon before it gets too cold here. What did you use for the washers at # 11 & #13? Did the tank just "lift out" or did you have to disconnect 11 & 13 first? thanks! I only had to disconnect the hoses from the tank fittings. I pulled the fittings from the tank to check the screen and to better aim them where I need them. If I knew I was going to get sidetracked and the car would still be on stands I would have ordered the correct fiber washers. The one under the screen I re-used, the one under the return I replaced with a viton washer I made. I don't have gas in it yet - hopefully it is well sealed! Getting the fuel lines to and from the two port pump under the steering rack was the hardest part of this project. In some ways drilling and welding in the sway bar mounts was easier! I only ran the positive lead through the tunnel, I grounded to the fuel pump mount on the inside under the tank. |
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| gothspeed |
Oct 24 2012, 10:19 AM
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#19
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Senior Member Group: Members Posts: 1,539 Joined: 3-February 09 From: SoCal Member No.: 10,019 Region Association: None |
Scott, thanks for following up on your progress! I have finally mounted my fuel pump under the steering rack. So far I think I will be running 12v power to the pump from the battery using a relay. The relay will in turn be triggered by the factory harness wires for the orignal fuel pump.
Since I am going with carbs for now, I will be going with the extra ground from the relay panel in the engine compartment. Did you run fuel pump power with the 'key only' or did you also include an oil pressure switch to control power to the pump? If you included an oil switch in the circuit, how was it done? I am under the impression the the swtich is open under pressure, which is the opposite of what one would need to complete the circuit. |
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| scott_in_nh |
Oct 27 2012, 07:18 AM
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#20
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Senior Member Group: Members Posts: 808 Joined: 10-December 10 From: Hampton, NH Member No.: 12,471 Region Association: North East States |
QUOTE(gothspeed @ Oct 24 2012, 12:19 PM) Scott, thanks for following up on your progress! I have finally mounted my fuel pump under the steering rack. So far I think I will be running 12v power to the pump from the battery using a relay. The relay will in turn be triggered by the factory harness wires for the orignal fuel pump. Since I am going with carbs for now, I will be going with the extra ground from the relay panel in the engine compartment. Did you run fuel pump power with the 'key only' or did you also include an oil pressure switch to control power to the pump? If you included an oil switch in the circuit, how was it done? I am under the impression the the swtich is open under pressure, which is the opposite of what one would need to complete the circuit. I am running D-jet so I am wired to the fuel pump terminal on the relay board. |
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