I installed a BVM UAT on thurs in my new Hotspot. I filled it up and wet tested my plumbing system and primed the lines.Today I went out to test fly the jet. There were zero air bubbles in the UAT, just fuel and fly. I believe filling up the UAT and letting the fuel sit in there saturates the bladder eliminating the bubble purging routine.I have done this several times and have never seen any air during my first run up.
V..
BTW the jet flys great...

May I ask you what is the orientation of the tank ?

Regards,

David |Gladwin.

So where does the air go that is in the sack? It can`t just disapear it must end up going down your fuel pipes when you prime ( purge ) your fuel lines.

jason

A bit off topic but:
Anyone know where I could get a replacement bottle for the UAT?
I have one that has been damaged in a crash but the sack and fittings are ok. BVM will not sell a separate bottle but I suppose it is a standard one ( may be in the US but not here in europe as you would expect!!)

Thanks
Florent

I believe that size bottle is available from McMaster-Carr.

David,
I mounted the tank vertical. Also it was filled initially thru the cap fitting.I topped off the fuel at the field and started the motor up, not one bubble came out of the UAT and went flying.
V..

Rider-60


I will send you one no charge I know what it is like.I'm looking for two of those Netto 1/2 liter shampoo bottles for my L-39 that thy only sell over in Europe. Send your info to me at [email protected] and I will get it in the mail.Paul

Vincent, I think that is the best orientation with the UAT, I have had no problems with the UAT inclined but endless problems with it horizontal until I carried out the purging with the tank vertical and using the engine fuel pump as the "primer". Thanks for your feedback. Regards, David Gladwin

McMaster Item #4293T76 Wide-Mouth Rectangular Polyethylene Bottle 4 oz, 2-3/8" X 1-1/2" Base, 4" Overall Height $ 1.30 Each

The UAT fittings have some sort of red thread locker on them. I used red Loctite 271 when I rebuilt one of mine. It's had fuel in it now for about 3 weeks and hasn't leaked.

Thomas Scientific also carries these ..


Wojtek

Thank you all for your answers especialy Paul!,
I will try to get you the shampoo bottles, do you have any pic or a description?
I suppose you would like toget them empty

Thanks
Florent

Hi

About those shampoo bottles. For the L39. Go here and ask Paul Gray. If he will send you some. He was nice to send me to, fore my L39.

http://www.rcuniverse.com/forum/L39%...1396336/tm.htm