Rotten fuel tubing R50T

['arry 'eadspeed]

There must be prev discusion on this but a search didn't reveal any .....

When doing year-end maintenance on my one-season-only (114 flts) Raptor 50 Titan I discovered the clunk line fuel tubing in the main tank had the appearance of a partially decomposed earthworm.

No big deal to change it for some real silicon tubing, but concerning to think of the likely outcome if not discovered ... especially for a beginner with no autorotaion ability.

Model aircraft fuel systems have been around since Jesus was making his own bolts. Where was Thunder Tiger?

[BarracudaHockey]

Most of us change that crappy clunk line out when building the kit. Its a common source of tuning problems and the higher the nitro the less time it lasts. The supplied thin line is of the theory that it needs to be thin and flexable.

I use Hayes neoprene line, cut it a few mm shorter than you think you'll need and make silicon fuel line keepers for it as outlined in this article, change it every few months.
http://www.rcuniverse.com/magazine/article_display.cfm?article_id=836

['arry 'eadspeed]

Thanks for the reply Andy, and the link to that article. It was comprehensive and useful. It made me want to go build another one!

Re the bearing greaser ... I assumed that the brgs were factory greased and did not try to add any: also because 1- it attracts dust and grit, and 2- oil from the fuel gets everywhere anyway. Am I mistaken?

BTW, I have lots of hours on my TRex 450 and its unlubed brgs don't seem to wear out.

[archiebald]

I change clunk lines twice a year...just to be sure.

[bigdwalker]

I did the same thing left it far to long and when I had tunning issues discovered it almost seemed decomposed, however it was still intact I finally chased the tuning issues to what appeared to be bits of clunk in my carb like fine white gunky stuff took the main needle out and pumped fuel in and thats what came out running 100% now though.http://www.helifreak.com/images/icons/icon7.gif
Smile

[BarracudaHockey]

The bearings are sheilded but not sealed. No the greaser doesn't make them attract dust and dirt, the bearings last alot longer that way. Infact when you do maintenance and push the grease in after the bearing has been on the heli for a while you will see nasty grease coming out.

I only lube the main shaft bearings on my minis when I build them.

['arry 'eadspeed]

Andy, I studied the info on bearings, greasing and the Greaser* on Pete's Hobbies site. Along with your info I have formed a different picture of it all.

It would be a PITA to lube the brgs at this point. I will prob obtain replacements, grease them, and hold till the existing ones start to fail.

Still learning ....;)

*I guess I will be buying one!

[grnmac1]

Hey guys,
I know this is an old thread, but i recently had to change my lines in my raptor. I notices that after 1 gallon of fuel my header tank line dropped of in the tank. I am using hayes fuel line, I changed them out (both header tank and main tank) and i noticed that my first tank of fuel turned black in the tanks. i am wondering if i got bad fuel lines or what. Is there a different kind of line to use? :confused:

[GunnyGlow]

Hey guys,
I know this is an old thread, but i recently had to change my lines in my raptor. I notices that after 1 gallon of fuel my header tank line dropped of in the tank. I am using hayes fuel line, I changed them out (both header tank and main tank) and i noticed that my first tank of fuel turned black in the tanks. i am wondering if i got bad fuel lines or what. Is there a different kind of line to use? :confused:

cut little pieces of fuel line and slip it OVER the existing fuel line where it fits over the clunk and where it attatches to the barb. Does that make sense?? As far as the black goes...it is from the material used in the hayes lines. It's fine....don't even worry about it.

[Ah Clem]

" I assumed that the brgs were factory greased and did not try to add any: also because 1- it attracts dust and grit, and 2- oil from the fuel gets everywhere anyway. Am I mistaken?"

As Andy mentioned, the bearings are sheilded, not sealed. They do need to be lubed-there is probably no lubrication from the factory.

I use light oil, some use grease, either way, they must be lubed.