fuel filters

[Bobs]

Is it necessary to run a fuel filter with gas engines? In all the photos of gassers I've seen I don't think there were any fuel filters on them. Also, where did everyone mount their fuel line fittings to the tank? I mounted mine as per the instructions across the top back of the tank but the clunk line isn't really flexible enough to reach everywhere. I've ordered a new tank and was thinking of mounting the double end fitting on the side of the tank and in the middle. That way the clunk will be able to reach all four corners better. I think Chris mentioned this is where he mounts his. At this point I'm just wondering if leaking would be a problem with the fitting on the side. Thanks for your suggestions. BTW, I'm finished building but waiting for blades. Could be in the air early next week. Just thought of one more question. Anyone using a Revolution Whip Antenna and, if so, how do you like it? Thanks again.

[Gyan]

It's been my experience to filter the fuel prior to pumping it into the heli so my filter is in the gas can. The whip antennae works well I have it mounted on the forward RH skid but I've had them break the wire off. I just ordered a metal based whip from Rick's where the wire plugs into it instead of the Revolution that is (weakly) soldered inside with no option to fix when it comes off.

[rjflyer]

Bobs, I was told NO in line fuel filter, causes air bubbles. Tank filter only. I mount my revolution whip inside the canopy on the front canopy stand off. I put my gas lines on the front of the tank and wished I had put them on the side.
It sounds like you are almost set and ready for the maiden flight, enjoy.

[Bobs]

Where did you guys mount your gas line fittings in the fuel tank? Is there any fuel leakage around the fittings after tightening the nuts? And thanks for the info on the antenna and fuel filter.

[rjflyer]

Bobs, I put my fittings at the top back of the tank, just above the rounded edge. It is on top so no leakage.

[Bobs]

rjflyer, can you tell me how long your clunk line hose is? I cut mine 4 3/8 inches long for a starter like the manual states but if you were climbing straight up I don't think the clunk can move to the back of the tank: the hose is too stiff. Also, are you using the stock clunk that came with the kit? Thanks.

[rjflyer]

Bobs, It has been a while but I would have cut mine per instructions, I don't even remember getting any with the kit, I am using the standard yellow tygon. No it is not very flexible. I don't do any 3d or mild aerobatics yet. But when I get close to a 1/4 tank I start to suck air and lean out.

[Bobs]

Thanks for the info, rj. As I mentioned above, I ordered a new tank and I'm going to mount the double end fitting on the side and in the middle of the tank. Unless there's a more flexible gas hose that I don't know about, this is the only way I can see to reach all four corners of the tank in either upright or inverted position. My only concern is the possibility of leaking with mounting the fitting in the middle and on the side of the tank.

[MarkWebber]

Mine is mounted in the end of the tank. When I store it on the hooks in my basement ceiling, full of fuel with the blades folded, it hangs tail low. I've yet to find any leaks. I can't imagine the position you're wanting to use being any more likely to leak.

[larrytoelle]

Howdy,

I've been using Hayes fuel line for the clunk since about April ... with no problem. It's a thin walled black line that gives the flexibility needed to reach all those corners. It's great stuff for both nitro and gas ...

http://www.ronlund.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=heli&Product_Code=HAY249&Category_Code=

LT

[Bobs]

Thanks, Larry. Sounds like that's the answer. I just ordered the Hayes fuel line and a Stens fuel filter from Rick's. Spectra G includes the Stens filter with their kits so I thought I'd try it.

[larrytoelle]

Howdy Bobs,

Let us know how that filter works out. I've developed a skepticism about gasoline fuel filters after running weedeaters, chainsaws, and other tools with these small gas engines.

A friend of mine has a saw shop, used by most of the commercial loggers out here and sees literally hundreds of saws a month. His opinion is ... if the filter is too fine, it'll cause a bunch of needless grief. The carb itself has a filter that will remove crap large enough to cause harm ... and those seldom get plugged ... especially if the fuel is filtered when filling up. On the other hand, the fine fuel filters sold as after-market are always the ones that will cause an engine to fail. As a result, he removes the in-tank filter and replaces it with a simple clunk with a coarse screen.

I'm not sure what is best for these Zenoah engines ... but currently I just use a clunk and filter the fuel as I fill-up and that's it. Even on engines that run in a dirty environment, such as chainsaws, I use the clunks he has given me ... which would filter out chunks large enough to plug the fuel line ... but not much smaller.

LT

[Bobs]

Well, so much for using the Stens filter. I did order the darn thing but I'll find another use for it other than on my Bergen. Surprisingly, though, like I mentioned above, a guy in our club just bought a Spectra G kit with the 231 Zenoah (TRM) and it included a Stens filter. I'll see how his works out and keep you posted; however, he's not building it until this winter and so it will be next spring before I have an answer. Thanks for bringing this to my attention.

[larrytoelle]

Howdy Bobs,

Ya know ... opinions are like ???holes ... everyone has one. That Sten filter might be just the ticket ... I wouldn't take my or anyone else's opinion to seriously. Topics like this can cause endless debate ... which was not my intention.

LT

[PaulH]

I'm using the stock clunk in my tank. The only fuel filter I have is the one on my Jersey Modeller fuel can/pump. I have no trouble with bubbles or anything in my fuel and the engine runs consistently.