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Mon Dec 02, 2013 1:03 am

Every once in a while the subject of a fuel shutoff valve comes up. Lots of people have used some sort of shutoff both here in the Bay forum and in some of the other Samba forums. The biggest reason a shutoff gets considered is the problem of potential fires if a gas leak develops from bad hose, connections, failed components or whatever. There are enough reminders by Samba people to inspect and replace fuel hose frequently because of the damaging formulations of new problem gas and also particular attention to filters, carb fittings, and whatever other issues in the engine compartment. Most other vehicles don't have the problem but with our fuel tank up high any gas leak might get a fire started and it will keep feeding the fire. We can have up to about 3/4 psi static head pressure in the lines from the tank to the pump and also gas flow up at carb level.

A lot of us have zeroed in on a 12V normally closed solenoid valve AFC 121 by Advanced Fuel Components if we want to automate the shutoff.

For a while with my bus I used a manual shutoff valve (a 1/4" ball valve) mainly to stop fuel flow because my carbs sometimes would drain into the engine case. Others have had that problem, it's a bummer but the shutoff takes care of it. That's another use for a shutoff other than fire safety along with possibly security, fuel system maintenance and maybe other reasons.

Here are some pics of what I finally ended up with as an overall solution to some of the fuel line issues. Putting a solenoid valve in the system is great if it always works which it probably will but the rare chance of it or the electrical powering it failing is always there. So mine also has a manual shutoff in parallel to easily get gas flowing if needed to keep from having a dead bus.
I've, or anyone I know, have never had any problems with the clear plastic cheapie $3 fuel filters. And you can see their condition and if they are filtering junk out of the gas. regardless, most people still warn about them. I couldn't find a clear filter that was quality and worthwhile. About all 50's era cars had a glass bowl that was removable and cleanable. Tom Powell has one mounted in a good location to keep the glass from getting broken. They were pretty slick but it seems as if they are a collector item only nowdays. As far as good inline filters go there are a lot of them with a steel canister body but they are either inline for using hose or oddball thread size.
AFC has their A-155 filter that has 1/4"npt connections and it can be opened up to clean the filter media. Also has internal magnets. Pressure wise it's way overkill and even though it's not transparent it's probably a decent solution. It is inline before the solenoid valve. AFC also has a similar solenoid valve with the same filter combined into one body.

I had really wanted to run steel tubing from the tank to the valves but almost went with hose since hose can be pinched off to stop flow for maintenance. But found a compact fuel valve to shut everything off at the tank. If I had know about that valve I would have used it instead of the other larger ball valve. And the whole thing could probably be simplified but it's what it is. The 1/4" inverted flare tubing ends were the hassle and I finally had Parker make me some lines. I couldn't form good double flares on brake line tubing from the FLAPS.

There still needs to be a flex connection going to the steel engine line which goes thru the front tin on a T-1. So Gates Barricade hose is still probably the best to use there. And with 1/4" hose barbs it will be OK at least with frequent inspections.

And there are various ways to wire up the valve. I had previously run an extra harness from the rear to the front so i'm going to use that instead of tapping into the coil or using a relay.

http://www.afcvalves.com/
http://www.afcvalves.com/mod121.html
Here is where you buy the AFC valves http://www.buyafcvalves.com/Home_Page.html
It is setup for a discount if you order with the code of "thesamba"

The cool little fuel line shutoff is from one of the local ParkerStores. They have a great selection of automotive and performance hose and fittings.
http://www.parker.com/portal/site/PARKER/menuitem....mt=default

Mon Dec 02, 2013 2:15 am

Should you use yellow teflon tape for fuel fittings?
I was told that when I did my glass bowl filter with shutoff valve.

From the internet, "There is special Teflon tape for petroleum. It's used mainly for natural gas, it's thicker than normal Teflon tape. Available at home depot or whatever, just ask for yellow teflon tape "

i don't know if there is any chemical difference in the white or yellow, but there are many opinions regarding teflon tape and gasoline. http://www.thesamba.com/vw/forum/viewtopic.php?p=4858872 and more info by google.

I don't think either of us will have problems with the teflon tape we've used in our installations because the teflon is more of a lubricant for the pipe thread fittings than a sealant. I'm sure we were both very careful not to allow the tape past the end of the fitting so that pieces of teflon did not get into the fuel system.

Aloha
tp

Mon Dec 02, 2013 9:21 am

Nice work, lets hope you never have to test the system. :wink:

One idea that I had on the fuel system which could be added onto what you have done would be to extend the original metal pipe on a Type 1 engine (or add one to a carbed Type 4 engine) all the way to the forward end of the tranny and then go to rubber. With metal line running from the tank to this same point you would have little rubber fuel line outside of the engine compartment. Combined with your electric fuel shut off or an anti-syphon fuel pump located at the front of the tranny this should give a fairly high degree of safety.

Mon Dec 02, 2013 10:07 am

Wildthings wrote: Nice work, lets hope you never have to test the system. :wink:
X2, that looks great!

Mon Dec 02, 2013 11:18 am

that looks really cool. So double shut off - one manual, the other solenoid-actuated by the ignition system.... slick!

I did install a cheap plastic 1/4 inch lawnmower shut off between the gas tank/filter/pump components and the engine compartment - mainly for easier engine in and out games...

Presently coming in useful as I install a different fuel pump and a fuel regulator.

Mon Dec 02, 2013 1:31 pm

Good job Mike. As far as the hard lines go I'm guessing that you basically used brake lines and fittings which would answer Tom's question about the teflon tape being needed. The double flare is what does the sealing, not the threads. You apparently tried to make your own lines but couldn't get the flares right. I've tried that too without much luck. Especially the VW "bubble flare". Most flaps have various lengths of premade brake lines and I wonder why that wouldn't work for you keeping in mind that you said you had Gates fabricate the lines for you.

Mon Dec 02, 2013 3:01 pm

A simplier method of doing a shutoff valve and an alternative to the solenoid valve is the old bug Fuel Reserve Petcock 111-209-021F. Supposidly the threads are the same as our tank outlet. It needs to be modified to plug off the taller inlet. And a cable or pullrod in the wheelwell or other handy location could be used to work the valve. For a good functioning fuel shutoff valve right at the tank it would probably be the easiest to do.

Tom Powell wrote: Should you use yellow teflon tape for fuel fittings?
Thanks Tom, NOW you mention it :lol:
Actually I have a roll of yellow tape that I use for any natural gas plumbing fittings around the house. Thought about using yellow but went with the white. Hope there won't be leaks. After years of designing and troubleshooting hydraulic systems I don't remember anything other than white teflon tape being used. Isn't the yellow tape relatively new?

Gary, none of the FLAPS had brake lines in the right lengths so i got longer ones and then shortened them. I rented the inverted flare tool from Autozone but it wouldn't do the initial invert. I think the problem was the actual tubing. iZt might have been double wall tube even though it's real thin wall. Parker used some much heavier wall tubing. BTW, Tom was talking about all the pipe thread connections.

Wildthings- you're right about the stock T-1 steel engine line. It ends right above the very worst spot. the hottest spot on the exhaust is not where we want gas drips. https://www.thesamba.com/vw/gallery/pix/691292.jpg

Mon Dec 02, 2013 9:31 pm

OP, that's one clean mother you have there. Looks new. I always thought about using a solenoid for an anti-theft device. Do what you did, but have a hidden button under the dash to power up a latching relay to open the valve. That way, the car thieves get it started and go about 15-30 seconds until the carb runs dry since they don't know about the solenoid. They'll probably be in the middle of traffic and not likely to be trouble shooting while blocking traffic. Just take off.

Latching relays use a momentary shot of power and stay engaged, until you shut off the power from the key. Then they go open again.

Tue Dec 03, 2013 8:38 am

I have wondered how this setup could/would work with a F.I. tank that has 2 outputs.

I understand why there is a return as the system provides more fuel than its demands, but why not have 1 outlet with a loop system, the fuel in the lines would recirculate and gravity flow from the tank would keep the line full. otherwise you need 2 shutoff systems to be thoroughly effective, which really makes things tight between the tank and transmision

Tue Dec 03, 2013 9:19 am

The color just represents the thickness of the tape, yellow is twice as thick as the standard white tape, but white tape can be had in the thicker material as well. If it doesn't leak I wouldn't worry about the thickness of the tape you used.

Tue Dec 03, 2013 4:47 pm

A fuel tank shut off valve was one of the best things I've installed on my bus. I used the same big red handled ball valve you used mounted to the body followed by a fuel filter then the pump. I did mine in AN fittings and the appropriate cloth braided hose. AN-4 line fits nice and snug on the fuel tank outlet.

Tue Dec 03, 2013 11:01 pm

Thanks for sharing the information :0)

Wed Dec 04, 2013 1:20 am

So if a fire did start and burn the wires to the solenoid, the expectation would be for the solenoid to close, correct? Just when I was feeling good about replacing all my fuel lines I have to read this! :)

Wed Dec 04, 2013 5:25 am

What is the life of the Rubber seals in the manual shutoff valve when exposed to Ethanol in the gas?

Wed Dec 04, 2013 7:00 am

lintbrush wrote: So if a fire did start and burn the wires to the solenoid, the expectation would be for the solenoid to close, correct? Just when I was feeling good about replacing all my fuel lines I have to read this! :)

Mike said that the solenoid was "normally closed" which means it needs power to open so yes, if the wires were to burn through the valve should close.

Wed Dec 04, 2013 10:09 am

aerosurfer wrote: I have wondered how this setup could/would work with a F.I. tank that has 2 outputs.

I understand why there is a return as the system provides more fuel than its demands, but why not have 1 outlet with a loop system, the fuel in the lines would recirculate and gravity flow from the tank would keep the line full. otherwise you need 2 shutoff systems to be thoroughly effective, which really makes things tight between the tank and transmision

This wouldn't work on FI tanks at all, since we don't have threads on the outlet. FI tanks have two hose barbs that a hose slips over and that's it. The only option for an FI tank is to modify it while its out of the car and free of all gas fumes. I think the pump drawing from the top through a long steel straw integrated with a shut-off valve would fit the bill with the FI tank, and the return could be piped into the filler neck. No fuel outlets on the bottom of the tank would be the way to go.

Wed Dec 04, 2013 11:38 am

George- the manual valves both have nylon or something similar and no rubber. The solenoid valve does have A Buna seal.

The FI tank complexity is just one more reason I am happy with the simplicity of the early Bays. Wildthings has mentioned a few times about going in thru the top on a late Bay tank. One concern you would have to deal with is that it will syphon and pour the same full tank full of gas on a fire.

Wed Dec 04, 2013 1:33 pm

Desertbusman wrote: George- the manual valves both have nylon or something similar and no rubber. The solenoid valve does have A Buna seal.

The FI tank complexity is just one more reason I am happy with the simplicity of the early Bays. Wildthings has mentioned a few times about going in thru the top on a late Bay tank. One concern you would have to deal with is that it will syphon and pour the same full tank full of gas on a fire.

I bought a shut off valve that had a nice shiny ball with two rubber seals at each end. I wonder if there are manufacturers that make this with just nylon or Ethanol resistant seals. I hate fires and especially the ones that crop up in the engine bay.

Wed Dec 04, 2013 2:32 pm

Anti-siphon valve, anyone?

They're standard issue on many boats, and can apply to the fuel return as easily as they apply to the supply side. And they require no power. When your pump stops sucking on the straw, the fuel stops moving.

Code of Federal Regulations, Title 33/Chapter I/Subchapter S/Part 183 /Subpart J/Section 183.568

http://www.law.cornell.edu/cfr/text/33/183.568

These are US Coast Guard regulations for hand built boats. The situation seems the same.

M

Wed Jan 08, 2014 10:45 am

saw a gas line ball valve at Lowe's for ~$7