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Wed Jan 08, 2014 10:58 am

webwalker wrote: Anti-siphon valve, anyone?

Wow... this is a simple,proven, industry-standard solution to the problem... and a quick check on eBay has 'em at 20 bucks.

How did we all miss this? Or is there something we're missing here?

Wed Jan 08, 2014 11:35 am

Desertbusman wrote: 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 saw this on the Machine 7 air cooled website here in the UK:

Link: http://www.machine7.com/product.php?xProd=13217&xSec=343

I have fitted a cut off solenoid, I like the look of this filter and assume it would be OK feeding my Type 4 engine, a bit pricey compared to a disposable filter, but am a bit worried about a stone hitting the underside of the bus and breaking the glass. Anyone used one of these things and how durable are they?

Wed Jan 08, 2014 3:10 pm

On my Vanagon, I added a spring loaded check valve to my return line close to the tank. It should prevent gravity back flow from the tank in case of a ruptured fuel line in the engine bay. I also used steel tubing in lieu of rubber hose wherever practical.

Wed Jan 08, 2014 6:10 pm

Vince Waldon wrote: webwalker wrote: Anti-siphon valve, anyone?
is there something we're missing here?

I think what your missing is that an Anti-siphon valve would only be of benefit with a fuel line comming out of the top of the tank like Wildthings has proposed. There is no siphon issue involved with the tank bottom connection.
But the spring function of a spring loaded check valve would be a good way to stop gravity flow from the bottom outlet. At a half a PSI per foot of head in the tank line a one pound or a two pound spring would work great. You wouldn't want more than that as it wouldn't be the greatest for the pump.

chimneyfish-That's a nice looking filter. Solve the glass breakage concern and it would be great. Here is how and where Tom Powell mounted his. At our custom car and hot rod show Saturday I noticed a few of early era cars and engines with the glass bowl filter.

Wed Jan 08, 2014 6:39 pm

Desertbusman wrote: chimneyfish-That's a nice looking filter. Solve the glass breakage concern and it would be great. Here is how and where Tom Powell mounted his. At our custom car and hot rod show Saturday I noticed a few of early era cars and engines with the glass bowl filter.

Thanks Desertbusman, that is interesting to see, my first thought was that it goes against our shared conventional wisdom on here to fit a filter in the engine bay, but that debate has mainly been around the cheap plastic filters. I'm assuming all the glass bowl filters you saw on Saturday were engine bay mounted? Another option if opting to mount one underneath could be fabricating a simple gravel guard, either rigid wire mesh (like the stuff used for headlight protectors) or just plain old metal plate, that would be easy to do. I am liking the look of these glass bowl filters, they appear a lot more 'substantial' for want of a better description.

Sun May 11, 2014 9:08 am

webwalker wrote: 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

The only concern I would have with this "Anti-siphon Valve" is that the gas tank is higher than the engine itself. Therefore this valve would be deemed inoperable because there could be no siphon effect taking place due to the elevation difference between the two. Thus rendering the siphon effect absent.

Sun May 11, 2014 10:20 am

8675-30-9 wrote: webwalker wrote: 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

The only concern I would have with this "Anti-siphon Valve" is that the gas tank is higher than the engine itself. Therefore this valve would be deemed inoperable because there could be no siphon effect taking place due to the elevation difference between the two. Thus rendering the siphon effect absent.

I understand what you think you are saying. Backup and try again. In small home built water craft (which the regulations are for) the engine is often very low and the (removable) fuel "tanks" are often in a compartment at the stern... Directly over the engine. Which is our identical dilemma.

As I said above, they act as form of check valve, where they are normally closed to prevent siphoning unless there there is suction on the demand side (pump side.) No suction, no flow. Therefore no siphon is possible.

quod erat demonstrandum, 'k?

Sat Jun 21, 2014 10:13 am

Fuel Shut-Off/Opossum
Fuel Shut-Off/Opossum

Fuel Shut-Off/rneithammer

Fri Dec 25, 2015 4:53 pm

Desertbusman wrote: 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.

I am installing this valve and want to run a wire to the coil - can anyone suggest the best place to run the wire on a 74 bus that is better than just drilling a hole in the engine tinware?

Edit - I worked it out myself: I ran the wire over the transmission and through a hole in the left hand side of the engine bay and connected it to the wire to the solenoid valve on the carby, which is connected the the +ve terminal on the coil

Sat Dec 26, 2015 7:28 am

Make sure the hole has a rubber grommet in it. Or over time the tin will cut threw the wire insulation and create a short.
Tcash

Sat Dec 26, 2015 9:41 am

Tcash wrote: Make sure the hole has a rubber grommet in it. Or over time the tin will cut threw the wire insulation and create a short.
Tcash

I would connect it to something fused, or add a fuse, for this reason.

Tue Dec 29, 2015 6:56 pm

Very super slick! Shame my bus has a non-threaded outlet. It is a carb tank but I added a teee so I could run fi. I just have two cheapie red shutoffs down there, more to simplifyy engine swaps than fire saftey. As far as hardlines go, I used nicopp brake line to do my entire bus front to back, flared super easy with my cheap amaon tubing flare tool, so would think if you wanted to do brake lines that would be the way to go. A roll of that stuff is a VERY worthhwile investment, insanely easy to work with.

Still jealous tho.

Tue Jan 12, 2016 1:43 am

I have installed the solenoid valve using AN fittings and the CB Performance fuel tank fitting and it works fine but there was a leak around the tank fitting. I have drained the tank (again - I really hate doing this) and removed the fitting and found that the viton o-ring was mangled.

I think that the end of the tank outlet nozzle is too sharp and has cut into the o-ring, rather than being a "blunt" surface where the o-ring can sit against. has anyone had this problem and how did you overcome it. Do you think I can replace the fitting with thread sealant instead of the o-ring? Any help appreciated.

A downside of installing the solenoid valve without a manual bypass valve is that to drain the tank you need to have the ignition on to open the valve. Normally you would remove the battery terminals before removing any fuel lines just in case so doing it "live" adds a little more risk to this job.

Tue Jan 12, 2016 8:32 am

Hard to say without a good picture of what you are dealing with. Sealant will eventually leak. Unless it was designed to seal gas tanks. These are usually epoxy and you would not be able to get the nipple off.
But use a flat file and file the fitting flat and debur the edges with a round file.
Lubricate the O'ring with Super Lube Synthetic Multi-Purpose Grease prt# 21030. (Walmart carries it) and do not over tighten.
Splash some gas in the tank and test for leaks.

Leaving the key on can fry the points and the coil. If it does not start you will know why. Check your dwell. Feel your coil, it may be a little warm but not hot to the touch.

Good luck
Tcash

Tue Jan 12, 2016 9:48 am

Mellow Yellow 74 wrote: ... Do you think I can replace the fitting with thread sealant instead of the o-ring? ... you need to have the ignition on to open the valve. ...

The thicker yellow teflon tape thread sealant for fuel lines is different than the thin white teflon tape for water lines. But, teflon tape might not be the correct solution. You should be able to use a jumper wire to open the valve with the ignition off. But, there will still be a risk of spark, fuel, and fire. Possibly minimal risk.

Aloha
tp

Tue Jan 12, 2016 11:10 am

Tcash wrote: Hard to say without a good picture of what you are dealing with. Sealant will eventually leak. Unless it was designed to seal gas tanks. These are usually epoxy and you would not be able to get the nipple off.
But use a flat file and file the fitting flat and debur the edges with a round file.
Lubricate the O'ring with Super Lube Synthetic Multi-Purpose Grease prt# 21030. (Walmart carries it) and do not over tighten.
Splash some gas in the tank and test for leaks.

Leaving the key on can fry the points and the coil. If it does not start you will know why. Check your dwell. Feel your coil, it may be a little warm but not hot to the touch.

Good luck
Tcash

There are some really good epoxy sealants for use with fuel....but they are not perfect for this long term. They generally will shrink a bit with age. This starts cracks and makes them susceptible to attack from fuel.

The best sealants for solvent use are polyester or urethanes. Actual fuel usage...gasoline and/or ethanol are best with polyester/urethane blends....like this

http://www.permatex.com/products-2/product-categor...ant-detail

Oddly...Indian Head gasket sealer works very well with gasoline. Its ingredients are wood rosin (which lasts forever, is not degraded by water, heat or UV and can only be dissolved by serious solvents) and ethanol, methanol and 2-propanol.
Ray

Tue Jan 12, 2016 11:35 am

pumpedto2365 wrote: saw a gas line ball valve at Lowe's for ~$7

For Gasoline or Natural Gas? Big difference.

Wed Nov 23, 2022 6:35 pm

Hi folks how have you mounted this valve in your application? I can drill and tap a couple holes but was curious on what y’all have done before I go that route

Fri Nov 25, 2022 2:15 pm

sblu wrote: Hi folks how have you mounted this valve in your application? I can drill and tap a couple holes but was curious on what y’all have done before I go that route

Here's a thread with some pictures on early bays. Someone mentions late bays on p.2, and that you'll need two lines for FI, but no pictures of that setup.
https://www.thesamba.com/vw/forum/viewtopic.php?t=555837

Fri Nov 25, 2022 5:13 pm

thanks for the tip!
copying it here in case someones following the thread