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Fuel system upgrade progress [message #242902] Mon, 10 March 2014 09:17 Go to previous message
SeanKidd is currently offline  SeanKidd   United States
Messages: 747
Registered: June 2012
Location: Northern Neck Virginia
Karma:
Senior Member
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

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