YS Plumbing
 

Not sure if anyone is interested or if this is an old idea, but it's new to me. :) I'm installing a YS .63 in a GP Reactor and came up with a slightly different way to route the necessary fuel and pressure lines. For anyone who has ever used a YS, you know that it's a closed fuel system. It makes use of a pressurized, regulated setup to deliver fuel to the carb from essentially anywhere on the plane. It allows you to place the tank farther away from the engine and still get reliable, consistent performance. Anyway, the typical installation makes use of T-fittings in the pressure and feed line, allowing you to bleed the pressure before refilling or draining the tank. Failure to relieve the pressure can result in a shower of glow fuel. :) Anyway, the lines coming off these T-fittings usually are sealed with plugs commonly called "fuel dots" and are accessed through holes in the side of the fuse.

For my Reactor, I assembled the tank with a three-line option. In addition to the conventional vent and cluck line, an additional clunk line was installed. This second clunk line is a dedicated fill/drain line. That is, it's used to fill the tank and drain the tank at the end of the flying session. Instead of using dots to access both the pressure and feed line, I installed two Fourmost Bulkhead Fittings in the side of the fuse. One of these goes to the dedicated fill/drain line in the tank and the other goes to a T-fitting installed in the pressure line, downstream from the check valve. For the uninitiated, the check valve is what maintains the pressure in the tank. This pressure is provided by a regulator mounted on the engine. As you can see below, this plumbing eliminates one of the T’s from the system and provides for an uninterrupted feed line to the engine. Here is a diagram of how it all goes together.

http://i57.photobucket.com/albums/g2...nkplumbing.jpg

In practice, the two bulkhead fittings use a "jumper" piece of fuel line to join them together, effectively pressurizing the tank via both the vent line and the fill/drain line. At the end of a flight, one simply pinches the jumper line shut and pulls it off the bulkhead fitting tapped into the pressure line. This vents the pressure in the tank without spraying fuel everywhere. Then, you can plug your fuel jug feed line into the jumper line and refuel or defuel your plane. On the plane, the actal fittings are much closer together than depicted in the diagram. The jumper line is only about 1.5 inches long.

http://i57.photobucket.com/albums/g2...r/fittings.jpg

To me, this setup seems easier than dots because there are no plugs to remove (and lose!), no lines to feed through the fuse side and only one connection to handle on the plane. On the negative side, the dots are less conspicuous and easier to hide. In the end, I suppose we have to go with whatever setup best suits our needs. I hope I was able to describe all this in adequate detail. :) If not, or if I've made some crucial error, please speak up and let me know.

Erik

RE: YS Plumbing
 

Sounds like a pretty good idea. I just got a YS 63 to go on my new plane and I used the fuel dot system. The only reason I did that was because I saw it online some were. I aslo know what happens when you dont open the vent fuel dot first. It was my first time refueling the plane and I didnt open the vent first. Well the fuel went on everything. I had to get some help from my dad so he could open the vent because the the fuel just went all over the place. I felt pretty stupid!:) Guess it means the motor is working good:D

RE: YS Plumbing
 

Erik... great idea... thanks for sharing. My current build uses my first YS motor and I was wondering about the fuel setup but hadn't gotten that far... so you give me a jump on that.

I have used an external loop before and have it on a Hanger 9 PT-19 currently. It makes filling and draining very easy. In that case it is a loop interruption in the tank to carb line. On the PT-19 the fiberglass cowl has a boss that made a great place to bring tubing out to attach the loop.

Can I ask how much pressure?... will fuel line blow off brass tubing? ... what about if a wire is soldered around the tubing?

RE: YS Plumbing
 

It does not blow off the fuel dots (at least not yet) but if you undo the fuel valve first the fuel will shoot a pretty fare.

This is the way I did it its not erik's way but its another idea. http://www.geistware.com/rcmodeling/...er/ys_main.htm (just scroll down until you see the gas tank set up.

RE: YS Plumbing
 

Thanks guys. I neglected to mention that this is my first YS engine as well. I was looking for confirmation that it would work as much as I was just wanting to share my plans. :)

RE: YS Plumbing
 

I just acquired my first YS and am not knowing which connection to hook up to which part of the tank..I need help
Joe [email protected]

RE: YS Plumbing
 

It would help if we knew which engine you have.

RE: YS Plumbing
 

Joe,

If you have any of the motors that use crank case pressure, the diagram at the top will get you very close. If you have one of the new DZ series of motors, 140, 160, or 170DZs, then it is totally different.

Archie

RE: YS Plumbing
 

I doubt if it would...but, I'm not sure I would want to "risk" the jumper hose blowing off in flight. I think I would still rather use fuel dots or just a piece of brass tubing inline or the one way valve if accessible. Just my $0.02.