Author Topic: Fuel Hose Sizes - 85 K20  (Read 8720 times)

Offline Doppleganger

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Fuel Hose Sizes - 85 K20
« on: June 08, 2018, 10:24:31 PM »
Hi fellas. Been reading here for eons, finally signed up and here's my attempt to win 'dumbest question of the year' award. 

I recently picked up a west coast (clean as a bell) 100k 85 Scottsdale K20 from the original owner.....82 yrs young. He 'interviewed' potential buyers to decide on who he would sell it to (said his son was an idiot so he wasn't getting it - lol). Told me he was glad 'mother was in the car when I called' as she told him I was the one who should get it. Way cool.  8)

Anyways, the truck has sat for a long while with no fuel in the tanks, etc.  I just got my fresh q-jet back from the mountain man in AR and he said I had debris and water in my tanks. I ordered new tanks - fuel gauge stops at 1/4 full on one tank - doesn't work at all on the other, so new senders too. While doing this I'd like to replace all my fuel lines as well. Can get new pre-bent hard lines.....but what about the hoses?

Anyone know off hand what the ID size and approximate amount needed of the fuel hose to replace it all?

Thanks in advance.

Offline Irish_Alley

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Re: Fuel Hose Sizes - 85 K20
« Reply #1 on: June 08, 2018, 10:38:45 PM »
welcome from maryland

3/8" supply, 5/16" vapor, 1/4" return

post some pictures when you get a chance
If you can’t tell yourself the truth, who can you tell it to?~Irish_Alley

When you have eliminated the impossible, whatever remains, however improbable, must be the truth ~Sherlock Holmes

Offline Rapid Roy

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Re: Fuel Hose Sizes - 85 K20
« Reply #2 on: June 09, 2018, 09:13:58 AM »
Welcome
1974 Cheyenne 10 LWB STOCK 350 W HEI /TH350/AC/4 BBL Quadrajet
Mopar by Birth
Chevy by Choice

Offline Doppleganger

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Re: Fuel Hose Sizes - 85 K20
« Reply #3 on: June 12, 2018, 03:24:39 PM »
Here's some pics. Sorry for the delay.

Its clean as a bell but will need alot to get back to Stage 0. Just turned 100k. The fella who sold it to me said his son was an idiot and he didn't exaggerate. Apparently they had an issue with the ignition lock so he swapped out a tilt wheel from another truck, so the shifter is semi-messed up and only the oil pressure gauge works - my guess is the power sources from the column was, like him - disturbed. He also swapped in a Holly 650 <600 miles ago (it will go too) - and in doing so pulled almost every vac line off there was. Canister has 2/3 of its line missing as does everything else. He also swapped in a newer distributor and Chinese made fuel pump (which will also disappear). Wiring under the hood is a potluck of chaos. After setting the floats and needles, it starts and runs great except for a hesitation at 'launch' (easy or hard). Being its from the left coast, it does have (whats left of) Calif emissions - there's toy factories in China waiting for all that stuff too....and might be part of its issues. Wish I had an untouched one here to use as a cheat sheet while I sort it all out.

The front calipers were both froze - pedal had 1/4" of travel to full drop-anchor mode. I know how the bugs on the windshield feel just before impact now. Swapped in new ones, rotors and brake lines (all had collapsed). Also repacked new bearings while it was all apart. All of the suspension was replaced a long time ago but is very tight.....probably little to no miles on them. He said it had not been driven for almost 2 years - he was having issues getting in and out of it. Got my Q-Jet overhauled by a fella in Arkansas and new tanks and senders.....debating when to do all that or wait til I (possibly) do something with the motor itself. It also had an aftermarket AC setup in the dash that isn't hooked up anymore either. I think its salvageable....nice shape just needed a new compressor until junior ripped everything out and put it in a box. Good lord.

Plans are (besides hunting the son down) - would love to swap in either Vortec heads and intake or just go late 90's motor and get them and the roller cam thataway. Also love the 4L80E idea.

We lived in SD but came to NW Ohio to care for my 90+ yr old inlaws. Father in law just passed and her ma has early dementia, so alot to do here in the meantime. The truck stuff is how I "relax". lol

« Last Edit: June 12, 2018, 03:47:34 PM by Doppleganger »

Offline 75gmck25

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Re: Fuel Hose Sizes - 85 K20
« Reply #4 on: June 24, 2018, 06:49:23 AM »
Considering the condition of your truck, replacing hard lines is probably not needed.  They are very durable, and should be fine.  However, with dual tanks there are a lot of different rubber lines that interconnect it all.   At the fuel solenoid/switch itself there will be at least six lines, then 3 more at each tank sending unit, and 3 more at the fuel pump.

When you replace the tanks, replace each section of rubber hose with new high quality hose that holds up better with ethanol gas additives.  The most durable hose will meet the SAE 30R9 spec, but you can get by with SAE 30R7 spec hose.  Don't be surprised by the price, since most sizes will be $1.00-$1.50 per foot.

Bruce

Offline Doppleganger

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Re: Fuel Hose Sizes - 85 K20
« Reply #5 on: July 12, 2018, 02:17:51 PM »
Thanks for the input. Only reason I would consider it (stainless) is if I dismantle the truck next year (newer drive train, paint and electrical) - just figured it would never be easier with everything out of the way. The stock lines would still have street value in this part of the world - or I'd keep them for a future need.