No overflow tank for fuel. |
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No overflow tank for fuel. |
Downerman |
Oct 13 2014, 11:10 AM
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#1
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
So, after restoring this 73 and having a blast with the Renegade aspect (love the way it drives).... I have a bit of a problem. Never paid any attention until I started to drive the car and getting this gas smell. Well it didn't take but 5 seconds once I actually looked at the line off the filler. The guy (PO) had just looped the line back through the 1/2" nipple into the fuel spill area. So, here's my question. What are you conversion guys doing/running on your rides. Are you using the stock overflow and charcoal unit with all the vacuum lines? Some modified versions?? Would love to know.
Attached is my current setup. I'm embarrassed that I never caught it. Oh, and for those who care to know, I replaced that old line and fitted a new line and bottle catch to see if that was my source of gas. It is..... Dave |
76-914 |
Oct 13 2014, 11:30 AM
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#2
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Repeat Offender & Resident Subaru Antagonist Group: Members Posts: 13,504 Joined: 23-January 09 From: Temecula, CA Member No.: 9,964 Region Association: Southern California |
Run it on the outside after you remove the valance then dump it into the intake.
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Cap'n Krusty |
Oct 13 2014, 12:03 PM
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#3
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Eliminating the charcoal evap unit results in gas fumes reaching the passenger compartment. That's just the way it is. The large line is for spillage, and runs down behind the tank through an opening in the body, venting to the open air. The evap system is different (but also COMPLETELY passive). Why people remove it is an absolute mystery to me. One 3mm line from the tank to the expansion tank surrounding the filler neck, one from the expansion tank to the evap can, a 12mm line from the fan causing or top cylinder tin to the evap can, and another to the air filter housing. Simple, effective, and you lose NO horsepower. If ever there were something you could call a "no brainer", this system is it. I'm sure you can find a place to put the fan housing hose. If you have a radiator fan, you could probably rig it there and get some air flow. You can source most of the system with a want ad here, or get hold of Bruce Stone.
The Cap'n |
Downerman |
Oct 13 2014, 01:57 PM
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#4
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
So, using the diagram below, I have no fan (Blow) power so to speak. I have a radiator with electric fans on them for cooling (Remember I have a renegade). I could easily create an inlet into my air cleaner for the final run but what would I use for that fan power?
Dave |
boxsterfan |
Oct 13 2014, 02:19 PM
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#5
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914's are kewl Group: Members Posts: 1,776 Joined: 6-June 03 From: San Ramon, CA Member No.: 791 Region Association: Northern California |
Eliminating the charcoal evap unit results in gas fumes reaching the passenger compartment. That's just the way it is. The large line is for spillage, and runs down behind the tank through an opening in the body, venting to the open air. The evap system is different (but also COMPLETELY passive). Why people remove it is an absolute mystery to me. One 3mm line from the tank to the expansion tank surrounding the filler neck, one from the expansion tank to the evap can, a 12mm line from the fan causing or top cylinder tin to the evap can, and another to the air filter housing. Simple, effective, and you lose NO horsepower. If ever there were something you could call a "no brainer", this system is it. I'm sure you can find a place to put the fan housing hose. If you have a radiator fan, you could probably rig it there and get some air flow. You can source most of the system with a want ad here, or get hold of Bruce Stone. The Cap'n Perhaps they were trying to save weight on the car? (IMG:style_emoticons/default/blink.gif) (IMG:style_emoticons/default/smoke.gif) (IMG:style_emoticons/default/biggrin.gif) |
Downerman |
Oct 13 2014, 04:31 PM
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#6
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Wondering how important flow from the fan (Stock 914) is? Do you think the system would run/ be efficient with suction from the air cleaner drawing that final leg? In addition I could run a hose up to the air inlet area (Front of the 914) near the radiator and air would be forced into the hose at speed.
Dave |
Porsche930dude |
Oct 13 2014, 05:53 PM
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#7
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Member Group: Members Posts: 399 Joined: 25-November 11 From: Vestal NY Member No.: 13,819 Region Association: None |
i ran that small hose down under the tank and out the bottom of the car. So if it spits a little wont stink up the car
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Downerman |
Oct 13 2014, 06:23 PM
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#8
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Trying to stay legal so to speak although that did cross my mind. Little note to us conversion guys. talked to a Summit Racing manager the other day and he told me to be ready that California was going to require smog on EVERYTHING from 1966 and up. All cars must have stock engines and smog systems (if any for early years).
Scaring the crap out of me right now. At least they should give us a referee like they used to for us guys that make mods. Did that with my Jetta powered Westy. Dave |
Cap'n Krusty |
Oct 13 2014, 06:39 PM
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#9
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
You were lucky to get the Westy approved, because the failure to get ARB approval put the guy selling the kits out of business. I did 2 conversions, and they both had to leave the state.
The Cap'n |
Dave_Darling |
Oct 13 2014, 10:49 PM
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#10
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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 |
... California was going to require smog on EVERYTHING from 1966 and up. Naah--they've always required smog on everything. It's just that they have let us out of getting tested. We still had to meet all the requirements, they just never checked up on us. It's a fine point, but I'm pretty sure that's how they're going to sell it... --DD |
Downerman |
Oct 14 2014, 09:42 AM
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#11
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
I sure hope your right on this one.
Dave ... California was going to require smog on EVERYTHING from 1966 and up. Naah--they've always required smog on everything. It's just that they have let us out of getting tested. We still had to meet all the requirements, they just never checked up on us. It's a fine point, but I'm pretty sure that's how they're going to sell it... --DD |
bulitt |
Oct 14 2014, 10:50 AM
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#12
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Achtzylinder Group: Members Posts: 4,188 Joined: 2-October 11 Member No.: 13,632 Region Association: South East States |
I believe I read Sir Andy's fix in some thread - Punch a hole in the large overflow hose and insert the smaller fume hose inside for several inches. Make sure it is a tight fit. Seems to work for him?
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Downerman |
Oct 14 2014, 01:38 PM
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#13
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Check this out..... found this Micro fan and has some impressive MBF ratings. I think this would work perfectly as a "Blow" source for the charcoal canister on my Renegade. Trying to make this system stock because we know it works and in my opinion it's the best way to go. Not knocking those that port it out the bottom but not the way I want to go.
Dave I believe I read Sir Andy's fix in some thread - Punch a hole in the large overflow hose and insert the smaller fume hose inside for several inches. Make sure it is a tight fit. Seems to work for him? |
Chris914n6 |
Oct 14 2014, 02:07 PM
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#14
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Jackstands are my life. Group: Members Posts: 3,321 Joined: 14-March 03 From: Las Vegas, NV Member No.: 431 Region Association: Southwest Region |
Later 75s & 76s have a more modern setup. That 1/8" hose goes to a big black plastic box that surrounds the filler. Then a 1/8" hose goes from that, to a tube with the fuel lines, to the intake. It's all vacuum.
Modern cars have a switch so it only flows during idle. The point is to capture the gas vapor so it doesn't enter the atmosphere. Run it to the carb, unless the manifold has a vacuum inlet. There should be no fluid, just vapor. I would think 40yo charcoal would no longer be activated, thus making it pointless to install. The 70s and 80s were a horrible time for emissions solutions. EDIT: 5v blower? |
r_towle |
Oct 14 2014, 07:38 PM
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#15
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Custom Member Group: Members Posts: 24,577 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
Run the little small vent line down the back and out the hole that the large spill line went through. Leave it hanging down an inch or so below the car to crest a Venturi effect.
It's old school and was like that up till the 70,s on lots of cars. The way you have it now, the fumes are captive inside the front trunk and seeping into the cabin. |
Downerman |
Oct 15 2014, 10:08 AM
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#16
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
Yeah 5V...... small, quiet, low CFM and it has a 100,000 hour failure rating at 20 degree's celsius. Shipped to the house it's $15.00 and would supply a nice moderate amount of air into the canister. Everything else I looked at would blow like a son of a gun.
Hey thanks everyone. I got all my parts in from Parts Heaven and just need to attach the line going to the air cleaner and of course mount the small blower up front. I'm convinced that this "Stock" setup (less the small blower) will work just fine. Dave Later 75s & 76s have a more modern setup. That 1/8" hose goes to a big black plastic box that surrounds the filler. Then a 1/8" hose goes from that, to a tube with the fuel lines, to the intake. It's all vacuum. Modern cars have a switch so it only flows during idle. The point is to capture the gas vapor so it doesn't enter the atmosphere. Run it to the carb, unless the manifold has a vacuum inlet. There should be no fluid, just vapor. I would think 40yo charcoal would no longer be activated, thus making it pointless to install. The 70s and 80s were a horrible time for emissions solutions. EDIT: 5v blower? |
Chris914n6 |
Oct 15 2014, 02:29 PM
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#17
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Jackstands are my life. Group: Members Posts: 3,321 Joined: 14-March 03 From: Las Vegas, NV Member No.: 431 Region Association: Southwest Region |
I was questioning the 5 volts part. Nothing in the car makes 5v so you would have to add a regulator gizmo to not kill it.
I would think you could find a 12v tiny blower on Mouser or Digikey. |
skeates |
Oct 15 2014, 04:06 PM
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#18
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Member Group: Members Posts: 218 Joined: 28-February 05 From: Sacramento, ca Member No.: 3,684 Region Association: Northern California |
Not sure that little guy will move enough air for you. It's spec'd for .57 CFM at .18" H20. Might be enough for a microchip in a laptop, but it's just gonna make noise in your car. Not sure exactly what kind of CFM you're going to need, but I'd shoot for something in the 2-5 CFM range. And 12 volts for sure.
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Downerman |
Oct 15 2014, 06:34 PM
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#19
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Member Group: Members Posts: 168 Joined: 23-April 09 From: Monterey County, California Member No.: 10,296 Region Association: None |
I know..... .57 was exactly (or near) what I was wanting because I don't think the original fan push was much either. I bet I don't even hear it. Yes, getting from 12V to 5V is super simple and yes I checked my favorite place (Digi-key) and no I did not like the 12V blowers I saw. To much flow, larger and I would bet noiser.
For the record, with everything in place except the tiny blower, I filled her up. Ran it through the tests... (Left turn sharp, left turn sweeper and hard aceleration and stops and guess what? Not one wiff of gasoline. Man I don't get this 12V thing. taking a device that runs 4-5 volts from 12V is nothing more than a tiny voltage regulator. There's a zillion sizes, types and brands. Oh well, to each their own. Dave Not sure that little guy will move enough air for you. It's spec'd for .57 CFM at .18" H20. Might be enough for a microchip in a laptop, but it's just gonna make noise in your car. Not sure exactly what kind of CFM you're going to need, but I'd shoot for something in the 2-5 CFM range. And 12 volts for sure. |
skeates |
Oct 15 2014, 06:58 PM
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#20
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Member Group: Members Posts: 218 Joined: 28-February 05 From: Sacramento, ca Member No.: 3,684 Region Association: Northern California |
I know..... .57 was exactly (or near) what I was wanting because I don't think the original fan push was much either. I bet I don't even hear it. Yes, getting from 12V to 5V is super simple and yes I checked my favorite place (Digi-key) and no I did not like the 12V blowers I saw. To much flow, larger and I would bet noiser. For the record, with everything in place except the tiny blower, I filled her up. Ran it through the tests... (Left turn sharp, left turn sweeper and hard aceleration and stops and guess what? Not one wiff of gasoline. Man I don't get this 12V thing. taking a device that runs 4-5 volts from 12V is nothing more than a tiny voltage regulator. There's a zillion sizes, types and brands. Oh well, to each their own. Dave No need to get your panties in a twist. Sounds like you are going into this with eyes wide open and have considered your specifications. We are simply trying to offer some advice and point out possible pit-falls later you could run into. There are many ways to skin a cat and you are certainly correct that a simple voltage regulator would allow you to run that fan off of a 12 Volt source. Please let us know how things turn out. |
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