REMOTE FUEL FILL VALVE
 

Bought a Great Planes Remote Fuel Fill Valve for a model I'm building. I see there are connections from the fuel tank, then from the valve to the carburator. My question is, what happens when the fuel tank is full, and, where does the overflow fuel go/exit?

RE: REMOTE FUEL FILL VALVE
 

A fuel valve as you describe is for a two line tank with the line from the fuel valve to the tank going to the clunk line. The second tank line is the vent line to the top of the air chamber in the tank. It simply gets routed to a convenient place where when the tank is being filled, either it is allowed to pee on the ground or into a temporary connected overflow bottle to indicate when the tank is full when filling.

The vent line is a critical part of the system as unless air is allowed in/out of the tank, the tank can't be filled/drained.

RE: REMOTE FUEL FILL VALVE
 

As you noted the connections on all such fill valves are inserted in the clunk line from the tank to the carburator or the main remote needle valve.

Overflow is the same as every simple two line system and will come out of the vent line from the tank Which is plugged into the muffler which is normally unplugged at the muffler to watch for a full tank.

My personal reccomendation is to avoid any third line as it is actually redundant and unnesesary. Also I would even avoid even the refueling valve altogether as they will at some point get dirt into the valve and cause running problems that will cause much headache. Its far better to use a simple two line system system and it even works well in cowled engines when done right plus it provides an exposed loop for you to use when learning the pinch tuning technique.


John

RE: REMOTE FUEL FILL VALVE
 

The engine and fuel lines for this aircraft will be completely within a cowl, so, short of having to take the cowl off each time I refuel, I don't see any other option than the Remote Fuel Valve. The muffler will exit from underneath the cowl, so, from what you're saying, I'll have to unhook the fuel line from the muffler for the overflow as I do now for my uncowled engine? Thanks for the help guy's.

RE: REMOTE FUEL FILL VALVE
 

RE: REMOTE FUEL FILL VALVE
 

The pressure line can stay connected and the fuel will just run out the muffler when filled. Some clubs with grass fields require a catch can. John uses the split line and has it come out of the cowl or fuse at some point and makes the set up easy and fool proof. It's just the main line and is split then held together with a piece of copper or brass tube. When John comes on I'm sure he will post some photos for you. One of the better ways to do it and nothing to ever go wrong.

RE: REMOTE FUEL FILL VALVE
 

Disagree. Without a third "fill line", you must T into the engine feed/clunk line. This works fine, of course, but I have had some issues with flooding while doing that. Unless you can block/pinch the line between the T and the carburetor, fuel will get to the carburetor during filling.

This is not an issue with most engines, I know. But it was a problem with my Laser 150 on two different airplanes. And yes, the carb rotor was closed. Didn't matter; the fuel was there, waiting and under some pressure, so when I cracked the throttle for starting trim, it poured in there and flooded the engine. Of course, the Laser has its carb in an odd place; but still...

Another option is one of the fuel filler jobs with no moving parts; when you insert the fueling probe, it blocks off the route to the carb. The Sullivan unit is an example, but it is a bit too big for a small airplane, IMO. I use this on my larger models.

I agree heartily that the "fuel valves", as extant in the DuBro and Hobbico units, are problems waiting to occur. In addition to the dirt/grunge issue already mentioned, the small probes are easy to misplace; and then you're done.

So, yes, there are better ways to skin this cat than a third fill line. But it is still a viable method.

.

RE: REMOTE FUEL FILL VALVE
 

Thanks GB.

Nope fueling valves or third lines are never needed and two line fueling is particularly effortless. I have something over fifty plug and play aircraft and the vast majority are glow with a few gassers up to 50cc and even a few controlline all are simple two line fuel systems. Many are cowled.

Here are shots on how its done on just two of them. There are many vairiations but can give no specifics on exact ideals untill you post what type engine and what is the mounting orientation (vertical, horizontal or inverted). For example the blue Corsair is a two stroke mounted horizontal the muffler is on the bottom there is no need to unplug the vent tube it will drip from the exhaust outlet immediately.

The biggest argument I hear every single time is I don,t want to cut my pretty cowl and of course I recite the five golden rules for cowled installations:

1. Let enough air in that front hole.

2. let even more air out that bottom hole

3. Provide a main needle extention fully outside the cowl and without using some custom tool.

4. Provide another hole for the low range needle so a tool can access without removing or fighting the cowl.

5. Provide a loop of the carb line out and back in the cowl that you can fuel from an practice pinch tunning (for two stroke learning pinch tuning will be an invaluable asset).

Failure to use the golden five can and will shorten the lifespan of your airplanes.

John

RE: REMOTE FUEL FILL VALVE
 

I too was once stubborn about third lines but since I have gone back completely to two line systems about ten years ago, its interesting virtually everyone at our local field has recognized the many advantage and also gone back. Its also interesting that since I have been posting about the method I have even received hate mail about it (good grief).

For those willing to give it a try in most cases will not go back to fueling valves or third lines.

For some years I had a pile of valves and finally someone suggested giving them away but thought what an awful thing to do to your buddys and at that point they were all discarded to the landfill.


I just gotta throw this out there and am sure it will stir anger with a lot of folks but forums are all about opinions and my opinion is the biggest waste of money as well as added headache that is perpertrated on all newbies the waste spent on fueling valves and toolbox power panels for glow flyers.


John

RE: REMOTE FUEL FILL VALVE
 

What system I use depends on the plane and make of tank. Most the engines I use are a closed pressurized system and I can use just a Tee fitting to run out a fill line through a fuel dot and for the pressure relief line or over fill. One thing that wasn't mentioned was the fuel filter John is using on his YAK to attach the two lines. How good of an idea is that!!! I don't care for the two part filters, had one come apart from vibration once, but I do install the crap trap filter inside my fuel tanks on the main line. I can't recall the last time I had any crud or dirt in one of my fuel regulators. Filters are a good idea!!;)Mater of fact, I forgot to install one in the engine I worked on yesterday when I put it back in the plane. I will go out now and install one. Surprise, it will be a two piece like John is using. I just happen to have a bunch of them on hand. Just because I don't care for something doesn't mean I don't use them!!:D

RE: REMOTE FUEL FILL VALVE
 

I'm with John on fuel valves amd power panels also, not needed! Two line or fuel dots and tees, thats what I use. One of the first things I tell newbies is not to go crazy buying everything they think they need. Do a lot of research instead, and talk to the guys at the local club and see what is being used,(and what isnt)!;)

RE: REMOTE FUEL FILL VALVE
 

I think all of us that have been in the hobby for any length of time have all tried the fueling valve though. When they work they are great. Once you have one stick it will be the last time you use one. In my case it stuck with the fueling tip installed. It stuck so well even when I got it home I couldn't get the tip out. Sense that time I have seen countless of them stick opened and the tank couldn't get pressurized. I ended up doing the split line like John uses that day at the field but I had to pull the cowl off to get at the lines. I know others that clean, oil and replace the O-ring in the valve on a regular basis and love them. Just too much work for me when there are easier systems to use.;) The split line is about as easy as they get!

RE: REMOTE FUEL FILL VALVE
 

John, big thanks for the pictures. Sorry I'm a pain, I'm just more of a visual guy than a read instructions and figure it out, especially when I've never dealt with a cowled engine! Is there another line that the fuels drains out of when the tank is full or do you just let it drain out of the muffler? Thanks again for the pics and all the other replies....very helpful.

RE: REMOTE FUEL FILL VALVE
 

John....The plane I'm going to build is a Hangar 9 RV8, the engine is a SAITO 72 AAC. The engine will be mounted horizontally with the valve covers toward theleft as you're looking at the front of the plane.

RE: REMOTE FUEL FILL VALVE
 

Your engine setup will be very simple in all likely hood the small Fourstroke muffler will protrude well away from the the bottom with the vent/pressure line exposed. This makes it easy to pull off the line if you like to watch for a full tank as you fill. If the muffler is anywhere near point downward you won't even have to pull the vent line off, it will instantly pour out the muffle and it cannot cause any flooding to the engine.

As far as another line, no there are only two lines needed the one that goes to the tanks clunk and its routed to the carburator. This is the line that is looped outside the cowl and cut there where a short piece of tube is inserted.

Next line is the tanks vent which goes to the muffler. All new conventional tanks come with only two holes through the rubber bungs. If you use a third line then this hole has to be punched through.

Here are a few more simple pictures to help explain.

John[8D]

RE: REMOTE FUEL FILL VALVE
 

Well, that clears everything up! Like somone on here mentioned, I should have researched and asked the question on this site before I went ahead and bought a Remote Fuel Valve! Thanks for the pictures and the help John and evryone else. Big help!

RE: REMOTE FUEL FILL VALVE
 

So what are you railing against? Valves or third lines????

I agree the valves are more trouble than they are worth. And I agree that a third line is, most times, unnecessarily complex. But don't tell me the third line system isn't viable or "never needed". I know better.

I'm not being stubborn. If you would read my post more closely, I stated that in SOME circumstances, a third line had been the better choice. I also stated that valves are a PITA.

.

RE: REMOTE FUEL FILL VALVE
 

Thank you LSP what I am 'railing aginst' is both fueling valves and third lines. That should be apparent and the reason I now never use either.

I agree with you completely on the fueling valves. Now I never said third lines with fuel dots won,t work of course they will with some additional work.

However third lines do have more failure modes than a two line system. Perhaps thats why I made the move back to two line system long ago and it was because of the most obvious one of all. Just one to many times shifting through the dirt lookiing for the lost fuel dot.

To this day the very few at our field who still use the third lines its only these fellows I do on occasion see on their knees shifting through the dirt.

I can say I have never found one yet that the simple split two line system that I have presented photos of would not work. And a third line system was actually needed, never.

John

RE: REMOTE FUEL FILL VALVE
 

The overflow WILL go to your tank vent line (usually connected to the muffler). The overflow will be just like any other fuel tank situation.

I have used the Du-Bro version of the fueling valve for decades without ever a problem.
Keeping a nice scale cowl is to be admired when it makes a killer presentation on the flight line. No need to gouge unsightly holes into and out of cowls.

Someone suggested "dirt" as a problem, but dirt is a problem with or without a fueling valve. Keep your refueling rig sanitary... simple enough?
Run an in-line filter between your fueling valve and the carb (do this with or without a refueling valve).

If the case of the overflow becomes a problem (unwanted splash onto the ground, filling the muffler leading to a flooded engine in certain mounted configurations, or just plain wasting fuel), you can always use a second refueling valve to catch the vent side overflow (into a fuel tank).

RE: REMOTE FUEL FILL VALVE
 

You know, when I down talk fuel filler valves I'm talking about the older style. I just pulled up the Dubro web site and they have a filler I have never tried and it looks pretty good?? Maybe there have been some improvements? There was no real description of how it works. It could be a good one??? Just a thought.

RE: REMOTE FUEL FILL VALVE
 

John....I noticed on the pictures you provided that you can't see where the fuel lines are connected when the linesare outside the cowl. Do you have the connection tucked inside the cowl?

RE: REMOTE FUEL FILL VALVE
 

No there are no connections inside the cowl, The rear line goes inside the cowl and back to the fuel tank the forward line goes inside the cowl and to the carburator or remote needle valve. the connection is in the middle of the external loop.

Look agine at the picture of the blue corsair with the fuel pump connected that fuel pump is pumping fuel directly into the fuel tank. That is also where its connected (very easily) when defueling. When that fuel pump line is removed the little piece of tube in the forward line is reconnected to the rear line and that exposed loop stays outside the cowl.

Also this exposed loop provides a place to pinch the line when the engine is running. If there is nowhere to pinch the line then you cannot tune to the pinch something that can be most important when using two stroke glow engines, If one cares to learn the technique.

John

RE: REMOTE FUEL FILL VALVE
 

TPL33 - Just my 0.02, I took John's advice last year and took every Quik-fill valve out of my Warbirds. Best thing I ever did. NO dead sticks, no running problems, no issues gettig fuel out of the tank at the end of the day. Those valves will cause you nothing but headacks and if the plane you are putting it in is not dead stick friendly, you are in for trouble.

RE: REMOTE FUEL FILL VALVE
 

I'll add my vote to avoiding possible places for air to leak in. Back in 2005, I built the Hanger 9 PT-19 using an Enya 1.20 four stroke. The PT-19 has a scale cowl boss that provided an excellent place to add a block inside to mount two pieces of copper tubing pointing aft from the boss. Yep, the tank gets hooked to one and the carb line to the other and an external loop of fuel tubing is used.

The setup has yielded no problems. It is easier to fill than a fuel dot plus one other huge item I've not seen any one mention. Almost every glow user knows that sooner or later a needle valve will need flushing. One can pressure up the tank to do it at the risk of a leak but the safer way is to provide a little pressure at the carb inlet. The loop does that with ease... just screw out the needle, pressure up the carb side of the loop and no concern for causing an internal tank or fuel line leak.

My addition to what has been mentioned is to show how well a loop lying along the cowl looks. Add a cheek boss and avoid the loop sticking out at a 90 degree angle. Use two pieces of copper mounted to a block inside the cowl. A slight bit of effort t get there... but very nice from then on. Oh.... use a piece of colored fuel line to match.

http://pages.suddenlink.net/arlyn/P0002438.JPG

RE: REMOTE FUEL FILL VALVE
 

"Different strokes for different folks"......I am one who uses the GP and Dubro fueling valves on cowled engines and like them. Yes, all the potential problums that John Buckner and Gray Beard mentioned are true, but I have learned all of their tricks and still consider them of value for the nice finished look and convenience. I've bought plenty so the is always extra filler probes in my flight box. My LHS has converted me to buying the Dubro brand, he claims they are better quality with less "O" ring failure. If you haven't used them before, try one and decide for your self. When new they have been trouble free for me, but after a couple of years they can start to stick etc.