oldtimer4759

hi,
I am using the yellowish or blue coloured fuel line, I have tried different thicknesses, but it is too stiff to use it on the clunk, if I set it up the clunk stays at the bottom of the tank, no good for a war bird doing loops and rolls.

any suggestions, I was thinking of trying some fuel line out of a brush cutter, or chain saw.

thanks, Oldtimer.

Tired Old Man

My Feedback: (1)

Don't do that, the stuff rots.

Use a heavier clunk if you plan on using yellow Tygon. If you wnat to use the best Tygon use "Type F". Or... spring for a foot of Viton (flexible type) and just forget about it for several years.

oldtimer4759

hi, OK, thanks for that, will see if I can get it local, I am building an ESM model, the black bung that goes into the fuel tank, is it safe to use with fuel, I left it in a bottle of petrol, (gas) for a couple of days, it seems to be OK, it didnt go mushy or swell up, or do I get the Dubro fuel safe one,
It was also suggested that I boil the fuel line, that will soften it up a bit, I tried a short bit of the yellow line that I have, it has improved it to the point it could be used.

thanks, Oldtimer.

Campgems

T O M, good post. A year or so back, my glow jug pickup line broke and a guy at the field gave me a short lenght of theYellow Tygon to use. Six months later it had the flexability of a pice of 1/2" hard copper tubing. Granted that this was with glow fuel, but I've always wondered what to use in the tank for gas. You just answered that for me. Thanks again.

Don

Campgems

I think it is Sullivan that is now selling a "bung for everything". Gass, glow or diesel.

Don

oldtimer4759

hi, thanks for the answers, I tried to get onto the Newbie to Gas general info earlier, it must be popular, I just tried it again, should be compulsory reading, it answered most of my questions on the first page,
good thread Bob Pastorello.

thanks Oldtimer.

krayzc-RCU

My Feedback: (31)

keep that line wet and it will stay softer ( do not drain the tank at the end of the day if your needs will allow)

karolh

Just for the peace of mind it gives I use a Dubro gas stopper everytime.

Karol

Jezmo

To add to Tired Old Man's post, the Tygon hose number I use is F-4040A. 3/32" ID is plenty of fuel flow for at least a 100cc engine and bends easier than the larger stuff. At 4 1/2 inches of line length a standard clunk will gravity pull it to all rear corners of the tank with ease. A shorter line length might require a heavier clunk such as the "Walbro" felt clunk that is common in most weed whackers. I recently picked up ten of them on Flea-Bay at a steal on price.

Edited to change the line size to 3/32". My goof, brain getting too old.

rc bugman

My Feedback: (30)

A couple of 5/16 nuts will slide over the tygon line and slide down on the clunk barb over the tubing for additional weight on the clunk.

I add them in every tank.

Elson

jedijody

My Feedback: (1)

When I open a new ARF that I'm going to put together, the first thing I do is find the fuel tank and all associated fuel system components that are included in the kit. I then throw it all in the nearest trash can. I've never found acceptable quality fuel system components in any Chinese ARF, none of them.

Been using water bottles for a while now but an appropriately sized DuBro tank, gas stopper, Walbro felt clunk, a short section of a soda straw (if the tank size warrants it), and some genuine 3/32" (medium) Tygon F-4040A fuel line will save you many headaches and quite possibly your plane.

I avoid the 1/8" sized Tygon as it's to big for most carb fittings, fuel T's, and brass tubing on 100cc and smaller planes. It may fit snug when new but after Tygon is exposed to fuel for a short time it gets softer and expands leading to leaks at fittings. If one doesn't use barbs and clamps in the tank it will just slide off the brass tubing leaving the clunk fitting high and dry. 3/32" fuel line is more than big enough for any engine up to at least 170cc.

TimBle

Neoprene and Viton fuel line of similar diameter is more flexible than Tygon.
Problem is where to get it...

Tired Old Man

My Feedback: (1)

There are several locations to order Viton, and they are the same locations most any other hardware or tool can be found. McMaster-Carr and MSC Direct. It's not cheap but the good stuff never is.

Jody makes a very good point above. Fuel lines do not have to be larger because they carry gas. 3/32" is muy beuno for most engines.

BarracudaHockey

My Feedback: (11)

http://www.redaerorc.com/accessories.html

av8tor1977

My Feedback: (6)

Yeah, I learned the hard way about ARF fuel stoppers/bungs. I built a CMP Christen Eagle. I put the supplied fuel stopper in gasoline for 24 hours and it was fine. No softness, slimy-ness, nor any other sign of deterioration. So I used it in the build. Big mistake. The maiden flight went beautifully and I loved the plane. Then two weeks later I flew the plane again, and had problems with the engine not running properly. Long story made short, the engine finally quit at a totally inopportune time, and the subsequent crash made the airplane a total "writeoff". Investigation revealed the tank stopper had partially disintegrated and bits of rubber got into the fuel system.

AV8TOR

TimBle

as long as it nitrile rubber or viton it will be ok for gasoline use. Viton is especialy important for E10 gasoline.

Tired Old Man

My Feedback: (1)

The fuel line thing has become waaaaaay too complicated.

It's quite simple: Tygon or Viton, owner picks. If the Tygon becomes stiff it was the wrong type but can be overcome with a heavier clunk. People going to gas have to leave the glow mentality of using parts common to glow tanls behind them. That includes eliminating the use of "fuel" filters that had been used with glow engines. They are functionally useless for gasoline engines. Step up to the plate and obtain appropriate equipment.

captinjohn

So very true...don,t ask me how I know ! Capt,n

blikseme300

My Feedback: (118)

TimBle,

We are spoiled here across the Atlantic. We have access to the stuff you want & desire. I use Tygon 3/32 in all my gassers together with DuBro brown stoppers in DuBro tanks. After many seasons the clunk line is still flexible and good to go. The information from Jody is spot on: use the correct Tygon and have barbs on the metal tubes.

Bliksem

Tired Old Man

My Feedback: (1)

If Jody and I were to write a book on gassers and set up would anyone buy it or would they wait for it to be copied onto the internet?

TimBle

print and they will come.


I do have smaller diameter tygon as well. Found a place for Viton as well, Stihl SA
Just need to find the right place

MetallicaJunkie

i keep my fuel line inside the tank to a minimal.... one or 2 inches at most, and the rest copper tubing .... if you see the pic attached,,,,thats how i used to do mine...the only difference is i now use a genuine Walbro felt clunk (125 527).... they really suck the tank dry... i tested it out on the ground... i let it idle out of gas and the tank was dryer than any std clunk set up ive ever used


the Listerine tank is my exception...its in a profile plane from VVRC and i used a big enough piece of copper tubing to prevent the clunk from ever moving forward where it doent belong... i was running low on copper 1/8th so i use the biggest piece i could find.

now i can happily say i wont ever have to mess with gas stoppers(dubro stoppers) ever again.... it becomes a P.I.T.A. to change them out especially when you solder on barbs...... you can buy a complete set of fittings from B7B Specialties to make your own custom water/soda/sports drink tank. 8oz for my 20cc 15.5 oz for my 50/55s and a 20 oz from my 80... and 24oz fro a soon to be 111 ans 10or12 oz for a dle 30

Edit they tygon im using was purchased from mcmastercar, i believe i bought 4040 as suggested here on RCU or FG

next time i swap out lines which will be a breeze... ill use the best....Viton....its expensive but, i wont need more than a foot or so to finish the internal plumbing in my tanks.. and use the tygon 4040 for the external lines

STUKA BARRY

I use about the same set ups yawl do, so I'll wait for the movie to come out.

apalsson

My Feedback: (1)

Tygon F-4040-A can be had in 50 foot rolls from lanwmower shops at a reasonable price. If you ask them for a metre only, they will ask a steep price but if you get them to order you a box, it normally comes at a reasonable price.
I pay approximately $60 for a box of 50' (15M) and am sure if I shopped around, I could find it cheaper.
Another thing to consider if people are concerned about the clunk line going stiff is to get the line with thinner wall thickness and have a piece of brass pipe inside the tank and use a short piece to tygon (the thinner one) to connect it to the stopper pipe. The clunk can then be attached in any way to that pipe, either soldered or with another short piece of tygon.
The possibilities are endless and can suit whatever requirements people have, just think outside the square

At any rate, any modeller shop should have an assortment of brass pipe of various dimensions and a few sizes (and thicknesses) of Tygon.
Only thing I avoid like the plaque is the stoppers (and iin most cases the tanks) that come supplied with the ARFs

captinjohn

Really.....a book may be great for people that do not do computers. I met a guy that does not do the internet at all. He had a DLE 30 and was trying to get it to run good enough to fly. He had a DLE sparkplug in it...I told him most people throw that plug away and install a CM6. He also did not have the snap-ring that goes on the outside of the metal boot. Also he did not have the inner spring installed for the metal boot. A friend of mine had a dremel too...so I took the ridges off the metal boot for hose clamp install. Got it running and he could not get it tunned good enough to idle. I said I cannot explaine it too good but I would tune it for him. That went well ...in about 3 min had it running good. But I cannot begine to imanage how many guys out there that do not get much help....because of no internet or someone willing to take the time to help. I bet there will be plenty of engines of all types to buy on ebay....because the operator did not have help. Lets hope they get help! Capt,n