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[GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323603] Fri, 08 September 2017 16:31 Go to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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Put in another new fuel pump. Didn't even get out of the drive when the new relay died. This relay is a small black one from Auto Zone. Any suggestions? Bob Dunahugh
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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323604 is a reply to message #323603] Fri, 08 September 2017 16:45 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
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Lots more Scotch. (Grin) But seriously, that pump shouldn't draw more than
12 or 15 amps. Most of those little cube relays have their amperage rating
stamped on them. I have a bunch of them, most are rated for 40 amps. But,
does the pump run continously or does it start and stop to maintain a
certain pressure. That might tax a relay beyond its rating by inducing a
collapsing magnetic field internally. Just my wild assed guess.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Sep 8, 2017 2:32 PM, "Bob Dunahugh" wrote:

> Put in another new fuel pump. Didn't even get out of the drive when the
> new relay died. This relay is a small black one from Auto Zone. Any
> suggestions? Bob Dunahugh
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323605 is a reply to message #323603] Fri, 08 September 2017 17:05 Go to previous messageGo to next message
Emery Stora is currently offline  Emery Stora   United States
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Registered: January 2011
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Senior Member
I suggest that you purchase a Bosch relay. Many of the cheaper “black boxes” don’t hold up.

Emery Stora
77 Kingsley
Frederick, CO

> On Sep 8, 2017, at 3:31 PM, Bob Dunahugh wrote:
>
> Put in another new fuel pump. Didn't even get out of the drive when the new relay died. This relay is a small black one from Auto Zone. Any suggestions? Bob Dunahugh
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org


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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323606 is a reply to message #323603] Fri, 08 September 2017 17:24 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Registered: July 2007
Location: Sydney, Australia
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Bob,

Here you go:

http://www.viaircorp.com/electrical/relays/

If you buy the 80 amp model I'd say you've got serious overkill!

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces-AT-list-DOT-gmcnet-DOT-org] On Behalf Of Bob Dunahugh
Sent: Friday, September 8, 2017 4:31 PM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit.

Put in another new fuel pump. Didn't even get out of the drive when the new relay died. This relay is a small black one from Auto
Zone. Any suggestions? Bob Dunahugh


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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323629 is a reply to message #323603] Sat, 09 September 2017 09:34 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
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Senior Member
If you are using 1 relay to drive 2 pumps, I would split the load and use another relay for each additional pump. Less communication of the power fluctuations generated by each pump that way and also makes troubleshooting much easier with each pump having a direct line to the battery.

Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323633 is a reply to message #323606] Sat, 09 September 2017 09:58 Go to previous messageGo to next message
richshoop is currently offline  richshoop   United States
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Registered: April 2017
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Member
You might try something from Cole Hersee. A primary supplier to all the truck manufacturers.

----- Original Message -----

From: "Rob Mueller"
To: "gmclist"
Sent: Friday, September 8, 2017 3:24:36 PM
Subject: Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit.

Bob,

Here you go:

http://www.viaircorp.com/electrical/relays/

If you buy the 80 amp model I'd say you've got serious overkill!

Regards,
Rob M.
The Pedantic Mechanic
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
USA '77 Kingsley - TZE 267V100808


-----Original Message-----
From: Gmclist [mailto:gmclist-bounces-AT-list-DOT-gmcnet-DOT-org] On Behalf Of Bob Dunahugh
Sent: Friday, September 8, 2017 4:31 PM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit.

Put in another new fuel pump. Didn't even get out of the drive when the new relay died. This relay is a small black one from Auto
Zone. Any suggestions? Bob Dunahugh


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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323639 is a reply to message #323603] Sat, 09 September 2017 11:19 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
Karma: 31
Senior Member

Just about any 12 volt relay will do. A fuel pump is a low current device. It does not have any high current start up requirements. My Cater P4070 draws less than 2 amps. I have a 3 amp fuse in line with it and have never blown it. I'm not quite sure of your wiring set up, but you can always go to the junk yard and get a few relays out of GM vehicles (or other brands) and wire one up with some small push on connectors.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323640 is a reply to message #323603] Sat, 09 September 2017 11:14 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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Terry. I'm not running both pumps at the same time. I've had the main/aux tank valve die on the road. So I wanted to have a backup fuel pump already installed. And get rid of that gas switch over valve. So now I have the dash gas tank switch operate a rely. The relay now runs the main tank pump till I switch over to the Aux tank pump. This setup works for EFI, or Carb systems. I still have my entire carb system in place with the Carter 4070 pump installed on the outside of the main frame. This pump only takes gas out of the main tank. Now I can't have tank valve fail because I don't have one. And if I have a main tank pump fails. I just turn on the aux tank pump. If all of my EFI fails. I can go back to the carb. And with the carb in place. I just won't have a vacuum advanced distributor. But I'll get home. And right now. I'm SO SO glad I didn't put my fuel pumps in the gas tanks. As I can change a fuel pump in 20 minutes.

Bob Dunahugh
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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323725 is a reply to message #323629] Sun, 10 September 2017 17:59 Go to previous messageGo to next message
rvanwin is currently offline  rvanwin   United States
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Registered: April 2007
Location: Battlefield, MO
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Bullitthead wrote on Sat, 09 September 2017 09:34
If you are using 1 relay to drive 2 pumps, I would split the load and use another relay for each additional pump. Less communication of the power fluctuations generated by each pump that way and also makes troubleshooting much easier with each pump having a direct line to the battery.

The relay Bob is using (or hopefully is using) is a 5 pin. When the relay is not energized the 12v from the EFI (which should be triggered by a normal relay) goes into the 5 pin relay then out to the main tank pump. When the relay is energized by the selector switch (switching to Aux), then the relay will switch the 12v to the other lug which should be connected to the Aux. Pump.

Bob, is this the way you have wired your setup? I think this is what we have discussed as the best way to wire the main and aux pumps.



Randy & Margie
'77 Eleganza II '403'
Battlefield, MO
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323745 is a reply to message #323640] Sun, 10 September 2017 23:26 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Registered: October 2010
Location: Cedar Rapids, IA
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Randy. I did go with your suggestion with the 5 pin relay. Thank you. The pumps are running with about 4 Amps. The rely is rated at 40 Amps. I just love this setup. Should have installed that setup when I had the carb. And Randy. My idle in drive is now at 725 RPMs. Is that close enough to keep my TB happy? Bob Dunahugh One happy sucker.


________________________________
From: Bob Dunahugh
Sent: Saturday, September 9, 2017 11:14 AM
To: gmclist-AT-list-DOT-gmcnet-DOT-org
Subject: RE: Need a GOOD relay to run my two fuel pumps. As my new China one just quit.


Terry. I'm not running both pumps at the same time. I've had the main/aux tank valve die on the road. So I wanted to have a backup fuel pump already installed. And get rid of that gas switch over valve. So now I have the dash gas tank switch operate a rely. The relay now runs the main tank pump till I switch over to the Aux tank pump. This setup works for EFI, or Carb systems. I still have my entire carb system in place with the Carter 4070 pump installed on the outside of the main frame. This pump only takes gas out of the main tank. Now I can't have tank valve fail because I don't have one. And if I have a main tank pump fails. I just turn on the aux tank pump. If all of my EFI fails. I can go back to the carb. And with the carb in place. I just won't have a vacuum advanced distributor. But I'll get home. And right now. I'm SO SO glad I didn't put my fuel pumps in the gas tanks. As I can change a fuel pump in 20 minutes.

Bob Dunahugh
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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323776 is a reply to message #323603] Mon, 11 September 2017 17:57 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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BobDunahugh wrote on Fri, 08 September 2017 16:31
Put in another new fuel pump. Didn't even get out of the drive when the new relay died. This relay is a small black one from Auto Zone. Any suggestions? Bob Dunahugh



Get your failed one open. Bring it to Elkhart. I had one of these cube relays fail. I popped it open and found an itty bitty relay inside the case. No way was that relay good for 30/40 amps.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323779 is a reply to message #323745] Mon, 11 September 2017 20:54 Go to previous messageGo to next message
rvanwin is currently offline  rvanwin   United States
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Registered: April 2007
Location: Battlefield, MO
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Senior Member

BobDunahugh wrote on Sun, 10 September 2017 23:26
Randy. I did go with your suggestion with the 5 pin relay. Thank you. The pumps are running with about 4 Amps. The rely is rated at 40 Amps. I just love this setup. Should have installed that setup when I had the carb. And Randy. My idle in drive is now at 725 RPMs. Is that close enough to keep my TB happy? Bob Dunahugh One happy sucker.



Bob,

Yes, that idle should be good. When you get here to Elkhart, I can put a monitor on and we can do the final adjustment of idle to get it dialed in properly. I can also check your fueling parameters and make any additional tweaks that might help it run even better.


Randy & Margie
'77 Eleganza II '403'
Battlefield, MO
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323794 is a reply to message #323603] Tue, 12 September 2017 12:33 Go to previous messageGo to next message
TR 1 is currently offline  TR 1   United States
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Mens mall is where I get relays. OEM relays are generally high quality, and they're like a buck or 2 at the pick n pull.

Bosch ones are ok... But I've replaced more than a few few on BMWs, Audis and VWs over the years... I prefer the Denso ones. I've been driving Mazda RX7s for 27 years now, and I currently own 4. None are my daily drivers anymore, but all have the original relays, and I've never replaced even one. Including my 85 which has 290K miles on it. Same goes for my friends with these cars. Heck, even my 74 Rotary Pickup, which I've owned for 10 years now, has all the original relays. However, the 74 has the old style with the metal caps and big copper coils that are more "serviceable" than the modern ones, but are heavy, and no better than the newer ones... at least, 30 years in they haven't proved to be so far.

Hard to beat 70s, 80s and 90s Japanese electronics for durability. Can't comment on the newer stuff, as it's still unproven, IMO.

FWIW, all modern GM vehicles I know of run Denso ignition components from the factory...

I have a whole box full of relays I've pulled off of Mazda's in JYs over the years. Used them on all sorts of projects... Lighting, electric fan setups, etc. I generally clip a nice section of the plug harness as well for splicing. When Mazda mounts a relay out in the elements, they generally include a rubber boot that goes over the relay and part of the harness as well. Nice to have if you also plan on mounting outside.

Like this:

http://www.ebay.com/itm/FA0151939-New-Genuine-Headlamp-Light-Retractor-Relay-OEM-For-1984-85-Mazda-RX-7-/182382442682?fits=Model%3ARX-7&hash=item2 a76d738ba:g:cscAAOSwo4pYSbvb&vxp=mtr

They're expensive if you buy them new, (which may be why they last so long)... But like a a couple bucks at the JY.



Mark S. '73 Painted Desert, Manny 1 Ton Front End, Howell Injection, Leigh Harrison 4bag and Rear Brakes, Fort Worth, TX
Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323795 is a reply to message #323745] Tue, 12 September 2017 12:34 Go to previous messageGo to next message
BobDunahugh is currently offline  BobDunahugh   United States
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Thanks so much for you help. I'll have my extra ECM that you programed the chip with my. Would it be much to program that ECM as a backup? We're leaving in the AM tomorrow. Bob





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Re: [GMCnet] Need a GOOD relay to run my two fuel pumps. As my new China one just quit. [message #323813 is a reply to message #323795] Tue, 12 September 2017 17:40 Go to previous message
rvanwin is currently offline  rvanwin   United States
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BobDunahugh wrote on Tue, 12 September 2017 12:34
Thanks so much for you help. I'll have my extra ECM that you programed the chip with my. Would it be much to program that ECM as a backup? We're leaving in the AM tomorrow. Bob





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No problem...


Randy & Margie
'77 Eleganza II '403'
Battlefield, MO
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