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Fuel system upgrade progress [message #242902] Mon, 10 March 2014 09:17 Go to next message
SeanKidd is currently offline  SeanKidd   United States
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Pretty busy weekend...I had some discoveries and pleasant surprises.
http://www.gmcmhphotos.com/photos/oddsnends/p53492-emptying-tanks.html
http://www.gmcmhphotos.com/photos/data/6323/image116.jpg

I rigged up one of my new 100 Micron pre-filters, Carter P4070 pump and pressure guage to my battery charger. The filter was attached to the hard line that feeds the mechanical pump. I confirmed the P4070, deadheaded; max output is 6 PSI. I used the battery charger's on/off switch to prevent any stray sparks, and quickly emptied the tanks using the selector switch when one ran dry...so dry, that nothing was at he low point drain. The remaining fuel combined turned out to be about a pint!

Despite spraying PB blaster on everything last week, I broke 1 J-bolt. I also crushed the fuel tee (I have a Type-1 fill) but it is restored thanks to those who helped. Tanks are out. I found it interesting that GM designed the tanks to be lowered for sender maintenance without removing the tanks, the J-hook and detent in the rear strap facilitate this. One would just need to drain the tank and remove the fill coupling. Why would GM rivet the tank straps to the tank? was there any buffer between the strap and the tank? I think I would want something to prevent metal to metal contact...maybe plasti-dip the straps?

My tanks were remarkably clean and the OEM GM fuel lines were equally remarkably pliable. I did find significant leaking around the Main Tank sender O-Ring.
http://www.gmcmhphotos.com/photos/fuel-tank-hard-line-project/p53515-source-of-fuel-smell.html
http://www.gmcmhphotos.com/photos/data/6560/image123.jpg
http://www.gmcmhphotos.com/photos/oddsnends/p53491-fuel-tank.html
http://www.gmcmhphotos.com/photos/data/6323/image115.jpg

The <warmer 50*> weather permitted me to degrease the exterior of the tanks...remnants of my maiden voyage oil line mishap still coated the tanks, I guess preventing any more rust. Not too bad, looks like the tanks were galvanized? but some surface rust had spread perhaps 30%.
http://www.gmcmhphotos.com/photos/fuel-tank-hard-line-project/p53514-tanks-cleaned.html
http://www.gmcmhphotos.com/photos/data/6560/image122.jpg

One sender has bad feedthrough...reading 107 ohms constant, reads good at the potentiometer, so I will just replace the passthrough, the second sender was reading 17-107 ohms, tweaking got me to 1.2 and 92 ohms....close enough, I'll use that one on the main tank.
As of last night I had 2 coats of Eastwood Rust converter on the tanks, 48 hour cure and I can prime and paint. All of my parts are here, 50' 3/8, 25' 5/16 CuNiFer...Cupernickel line and all brass flare fittings. Dual pumps, 30 mesh strainers, 100 micron pre-filter, carter P4070, check valves, AC Delco GF62 filter, Henderson return line, separate vents.


Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: Fuel system upgrade progress [message #243991 is a reply to message #242902] Mon, 17 March 2014 19:04 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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Location: Northern Neck Virginia
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Update:
Only had one nice day...it got up to 60*. I scrubbed and degreased the frame, and applied Eastwood rust converter. I did manage to get all the electric done.
Here is my safety switch and new oil pressure sender.
http://www.gmcmhphotos.com/photos/data/6560/image132.jpg
http://www.gmcmhphotos.com/photos/data/6560/image132.jpg
Here are the relays,I will eventually post my schematic.
The safety switch provides power the NC side of one relay (main tank) the OEM tank selector now energizes the relay and switches to the NO side of the relay (aux). If the oil pressure safety switch opens (low pressure) it cuts power to either pump.
Simultaneously, the second relay, energized by the alternator feed, NO terminal powers the green glowing ring on my prime button, loss of power, the NC side powers a flashing red light with audible alarm. Prime button is currently located on my air compressor panel (I'm missing the panel under the steering column...eventually it will be relocated there.
http://www.gmcmhphotos.com/photos/data/6560/image131.jpg
http://www.gmcmhphotos.com/photos/data/6560/image131.jpg
http://www.gmcmhphotos.com/photos/data/6560/image130.jpg
http://www.gmcmhphotos.com/photos/data/6560/image130.jpg
The audible flashing alarm fit next to the windshield wiper control, just needed a hole in the plastic.
http://www.gmcmhphotos.com/photos/data/6560/image128.jpg
http://www.gmcmhphotos.com/photos/data/6560/image128.jpg
http://www.gmcmhphotos.com/photos/data/6560/image129.jpg
http://www.gmcmhphotos.com/photos/data/6560/image129.jpg


Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers

[Updated on: Mon, 17 March 2014 19:18]

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Re: Fuel system upgrade progress [message #243994 is a reply to message #242902] Mon, 17 March 2014 19:37 Go to previous messageGo to next message
Bob de Kruyff   United States
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"" Why would GM rivet the tank straps to the tank? was ""

Assembly process-nothing more, nothing less.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: Fuel system upgrade progress [message #244015 is a reply to message #243994] Mon, 17 March 2014 21:19 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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Looking good.

76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: Fuel system upgrade progress [message #244028 is a reply to message #242902] Mon, 17 March 2014 21:49 Go to previous messageGo to next message
noi is currently offline  noi   United States
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Greetings:

I drilled mine out so that I could have the straps and bracket powder coated.

Hadn't thought about putting a "top" coating of Plasti-Dip on the strap/tank interface - Not a bad idea, think I'll do that as well.

Thanks,

Carl P.
76 Birchaven
South of Fremont
Re: Fuel system upgrade progress [message #244052 is a reply to message #242902] Tue, 18 March 2014 01:15 Go to previous messageGo to next message
John Hunt is currently offline  John Hunt   United States
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Hi Sean - looking great. I would really like to see your schematic - I like the approach you're taking and I'm just about to do this. For some reason try as I might I'm seriously electrically challenged - I can do it, but I sure have to think hard about it and appreciate all the guidance from this group in this area.

I'm ceramic-coating the exterior of my newly restored tanks right now and have collected just about all of the Polyarmour, Parker fittings, and in-tank pumps. Can't wait to get this done.

John
"76 Eleganza II
Orange County, CA


1976 Eleganza II, 1969 Lotus Elan Plus 2, 1978 Merlyn Formula Ford, 1981 Lola Sports 2000
Re: Fuel system upgrade progress [message #244055 is a reply to message #242902] Tue, 18 March 2014 04:32 Go to previous messageGo to next message
kerry pinkerton is currently offline  kerry pinkerton   United States
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Some of my antique MOPARs, had a stiff welting of some kind between the tanks and straps. Impregnated with tar or similar.

Thanks for posting. Gotta do the same job this summer.


Kerry Pinkerton - North Alabama Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
Re: Fuel system upgrade progress [message #244056 is a reply to message #242902] Tue, 18 March 2014 06:02 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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The audible warning idea came from Bob de Kruyff....I will digitize my schematic to share, it is really derived from bits and pieces of the GMCNet collective...resistance is futile.

Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: Fuel system upgrade progress [message #244940 is a reply to message #243991] Tue, 25 March 2014 06:58 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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Sean,

I saw on another thread you were using dual carter 4070s before the selector. Where are you mounting them? There is no room on mine without moving the selector forward.


76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: Fuel system upgrade progress [message #244943 is a reply to message #242902] Tue, 25 March 2014 07:20 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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Joe, I'm copying Ken Henderson's system layout...creating a bracket just forward of the aux tank, one pump on either side of new bracket, take a look at Ken's.

I'm eliminating the selector. I will have one pump per tank, check valves are required to prevent back feeding to other tank. Selector switch now controls a relay, 2 new 12V 12 AWG feeds to the pumps. High micron filters (100) will protect the inlet side of the pump, outlet will tee into one of JimKs Cadillac filter (5 micron) to protect the carb. Its redundant, but won't leave me stranded.

http://www.gmcmhphotos.com/photos/data/5494/010_-_Dual_Fuel_Pumps.JPG
http://www.gmcmhphotos.com/photos/data/5494/010_-_Dual_Fuel_Pumps.JPG


Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers

[Updated on: Tue, 25 March 2014 07:21]

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Re: Fuel system upgrade progress [message #244954 is a reply to message #244943] Tue, 25 March 2014 08:37 Go to previous messageGo to next message
corleyw is currently offline  corleyw   United States
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I don't know about the particular pumps you are using, but many fuel pumps already have an internal check valve, eliminating the need for external check valves. Did you try blowing in the outlet to check that?

Corley '76 Glenbrook 29 other vehicles
Re: Fuel system upgrade progress [message #244975 is a reply to message #244954] Tue, 25 March 2014 11:08 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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corleyw wrote on Tue, 25 March 2014 06:37

I don't know about the particular pumps you are using, but many fuel pumps already have an internal check valve, eliminating the need for external check valves. Did you try blowing in the outlet to check that?


Trust me the carter pumps don't have internal check valves.


Roy Keen Minden,NV 76 X Glenbrook
Re: Fuel system upgrade progress [message #244980 is a reply to message #242902] Tue, 25 March 2014 11:31 Go to previous messageGo to next message
habbyguy is currently offline  habbyguy   United States
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I've always been wary of oil pressure fuel cut-off systems (though I'll probably end up with one when I finally install my fuel injection system, since it's built into the computer I'll be installing).

I prefer to have a visual / audible alert for low oil pressure, rather than having my engine "surprise me" when I least expect it (think "chugging up a steep hill at low RPM").


Mark Hickey Mesa, AZ 1978 Royale Center Kitchen
Re: Fuel system upgrade progress [message #244986 is a reply to message #244980] Tue, 25 March 2014 11:42 Go to previous messageGo to next message
Bob de Kruyff   United States
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habbyguy wrote on Tue, 25 March 2014 10:31

I've always been wary of oil pressure fuel cut-off systems (though I'll probably end up with one when I finally install my fuel injection system, since it's built into the computer I'll be installing).

I prefer to have a visual / audible alert for low oil pressure, rather than having my engine "surprise me" when I least expect it (think "chugging up a steep hill at low RPM").


I have a buzzer that alerts me of low pressure since I think I only ocassionally look at the gages. However, it relies on the additional pressure sender switch that I suppose could go bad. It's the same switch that controls my "standby" electric fuel pump. It sure is aggravating though when I have the ignition on and the engine not running.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: [GMCnet] Fuel system upgrade progress [message #245050 is a reply to message #244980] Tue, 25 March 2014 16:40 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Mark,

Here you go: http://www.digi-panel.com/index.html

Regards,
Rob M.
Sydney, Australia
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426

-----Original Message-----
From: Mark

I've always been wary of oil pressure fuel cut-off systems (though I'll probably end up with one when I finally install my fuel
injection system, since it's built into the computer I'll be installing).

I prefer to have a visual / audible alert for low oil pressure, rather than having my engine "surprise me" when I least expect it
(think "chugging up a steep hill at low RPM").
--
Mark

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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] Fuel system upgrade progress [message #245070 is a reply to message #245050] Tue, 25 March 2014 18:23 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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Triggering off the oil is better than not at all.

Was pretty easy to hook up a relay that triggered off the coil being energized, for the fuel pump shutoff on the 72 bavaria - was an old school coil. Haven't looked where to hook to for that same setup in the GMC.

Until recently I did not think I had an electric pump! Very Happy


76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.

[Updated on: Tue, 25 March 2014 18:24]

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Re: Fuel system upgrade progress [message #245642 is a reply to message #242902] Sat, 29 March 2014 07:46 Go to previous messageGo to next message
SeanKidd is currently offline  SeanKidd   United States
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Here's what I did...typical Bosch 30A relay, powered from ignition source 12V, through oil pressure safety switch. Audible alarm/flashing light warns immediately any time that switch opens, when the switch is closed, the prime switch glowing green ring illuminates. JWID Very Happy
http://www.gmcmhphotos.com/photos/data/6560/image135.jpg
http://www.gmcmhphotos.com/photos/data/6560/image135.jpg


Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
Re: Fuel system upgrade progress [message #245643 is a reply to message #245642] Sat, 29 March 2014 07:57 Go to previous messageGo to next message
Joe Weir is currently offline  Joe Weir   United States
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Thanks, Sean. Cool set up.



76 Birchaven - "Wicked Mistress" - New engine, trans, alum radiator, brakes, Sully airbags, fuel lines, seats, adult beverage center... those Coachmen guys were really thinking about us second hand owners by including that beverage center... Columbia, SC.
Re: [GMCnet] Fuel system upgrade progress [message #245644 is a reply to message #245642] Sat, 29 March 2014 07:58 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Good work, Sean. Including the failure warning may prove useful; I've had
several LOP switches quit, leading to peculiar problems. For example,
after one engine change it would run only a few yards or a few miles.
Turned out to be the boost pump, which was on the LOP switch, was
partially or completely filling the fuel accumulator dependent on how long
it took to start the engine. The high pressure pump was, at that time, not
on the LOP, only controlled by the computer. Had me baffled for a couple
of days. If I'd included a light, as you have, the failed LOP would have
been indicated instantly.

Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI & EBL
www.gmcwipersetc.com


On Sat, Mar 29, 2014 at 7:46 AM, Sean Kidd wrote:

>
>
> Here's what I did...typical Bosch 30A relay, powered from ignition source
> 12V, through oil pressure safety switch. Audible alarm/flashing light
> warns immediately any time that switch opens, when the switch is closed,
> the prime switch glowing green ring illuminates. JWID :d
> http://www.gmcmhphotos.com/photos/data/6560/image135.jpg
>
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Fuel system upgrade progress [message #245681 is a reply to message #242902] Sat, 29 March 2014 13:37 Go to previous messageGo to previous message
SeanKidd is currently offline  SeanKidd   United States
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Ok, here is my strainer...in lieu of socks, I'm using this #30 mesh stainless steel. I had hoped on brazing or soldering it...no chance, nothing would stick to it and my mig burned right through. I wound up painstakingly weaving the ends of the wires through and bending them back. The external 100 micron filter will protect the pump, and the 10 micron paper element in the Delco filter will get the small stuff.

http://www.gmcmhphotos.com/photos/data/6560/image136.jpg
http://www.gmcmhphotos.com/photos/data/6560/image136.jpg

Here it is on the sender, I will probably put a worm clamp on to keep it in place.
http://www.gmcmhphotos.com/photos/data/6560/image137.jpg
http://www.gmcmhphotos.com/photos/data/6560/image137.jpg


Sean and Stephanie
73 Ex-CanyonLands 26' #317 "Oliver"
Hubler 1-Ton, Quad-Bags, Rear Disc, Reaction Arms, P.Huber TBs, 3.70:1 LSD Honda 6500 inverter gen.
Colonial Travelers
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