Questions and Answers If you have general RC questions or answers discuss it here.

Avastar fuel tank

Reply
Old 08-19-2012, 07:20 PM
  #1
gphil
Thread Starter
 
Join Date: Oct 2011
Location: Elberton, GA
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default Avastar fuel tank

Been looking for a fuel tank for the Avastar. Plenty out there but if I remember correctly a 270c/c is the size with only two tubes . The one closet to it has three,,,,,I guess it is an overflow vent ?? Point me to a supplier. I think it has to be one that will only fit this plane. HCAA3747 is a number I saw and wrote down. Ok thanks. gphil
gphil is offline  
Reply With Quote
Old 08-19-2012, 08:41 PM
  #2
spoondude
 
Join Date: Jul 2004
Location: Danvers, MA
Posts: 1
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

I also have an Avistar awesome little airframe. I put in an OS 46ax and discover that the stock fuel tank only provides barely 10 minutes flight time.
I am going to try to fit a Sullivan 12 Oz flex tank. I have looked through tower hobbies, and a few other mail order type sites, and haven't found a better fit yet.

The flex tank is just barely oversized in one dimension, but longer than the stock. being flexible, (I squeezed one) it should definitely fit. When it arrives, I will
use a razor saw or knife to cut away some of the inner parts of the former ribs so I can addd the tank PLUS a bit of latex foam.

I hope this helps. :-)

spoondude is offline  
Reply With Quote
Old 08-20-2012, 03:03 AM
  #3
gphil
Thread Starter
 
Join Date: Oct 2011
Location: Elberton, GA
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Thanks guy. I also noticed that the Nexstar has the same size with the exception of the third line and being new I am assumeing this is either a top vent or filler line with an extra clunk. I have been getting longer flights than ten minutes but then I have only a .40 size engine. Thanks gphil
gphil is offline  
Reply With Quote
Old 08-20-2012, 08:29 AM
  #4
JohnBuckner
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,323
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Give the Hayes 'O' ring type tank a shot:

http://www3.towerhobbies.com/cgi-bin...K830&P=RF#tech

These tanks are far easier to assemble, are more reliable with no leakage problems from age or setting and withstand repeated removeal's of the plug. They are for two line systems and what I use on almost everything except for a few tettra bubbless types for some competition RC types and a few controlline airplanes.

You also may be able to use the 11 ounce if you prefer with some trimming described by Spoondude.

John
JohnBuckner is offline  
Reply With Quote
Old 08-20-2012, 12:46 PM
  #5
gphil
Thread Starter
 
Join Date: Oct 2011
Location: Elberton, GA
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

the way the Avastar is constructed, the chin would put the tank too far back in the fuze. The tank I have now is square and fits snug against the firewall with the pulg sticking out into the area where the engine lives. I am sure that I am making a problem out of nothing but don't want to create more problems than needed. Thanks for the info however. gphil
gphil is offline  
Reply With Quote
Old 08-20-2012, 02:46 PM
  #6
JohnBuckner
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,323
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Quote:
ORIGINAL: gphil

The tank I have now is square and fits snug against the firewall

GP now think about that just a moment. Now I am sure you have read about packing the tank with foam and such to prevent foaming but here we are jamming the tanks front end and bung hard aginst the highest point of vibration in the entire airframe aft of the engine mount.

Kinda contradictory Huh well seems that way to me. Heres the disclaimer - in my opinion - That is a very poor design and left over from many years ago. There is no need to force the tank up aginst the firewall, none at all.

Your airplane is pretty much a genaric forty sized trainer and there is no way you could not use at minimum an eight ounce hayes or any other style tank for that matter. You likely could even fit an eleven ounce hayes.

The trouble with stock tanks is inconsistancy most arfs will have differant tanks included from time to time or even from container load to container load. And searching for an exact copy is often a waste of time. Now is the time to improve your fuel system.

Also on conventional tanks you said they are all for three line systems in an earlier post but that is not normally the case. Every new aftermarket conventional tank I have ever used or seen has three holes in the compression caps but the rubber bung has only two holes fully opened. So its up to you to puncture the third hole if you want to use a third line.

Try the Hayes and you will not be sorry.

John

Here are closeups of the Hayes fitting to get an idea of how they work. The plug is hard plastic and has an 'O' ring. The steel ring prevents any splitting that can occur on older designs. The tower website does not illustrate these at all.

The Hayes is a bit longer but is is also narrower allowing plenty of room for the throttle in a genaric trainer and the tank is usually positioned high enough to allow the nosewheel pushrod to go underneath. There is no problem allowing the tanks rear to be slightly further aft.

Attached Thumbnails
Click image for larger version

Name:	Qo38984.jpg
Views:	11
Size:	228.3 KB
ID:	1793649   Click image for larger version

Name:	Yt62834.jpg
Views:	7
Size:	158.5 KB
ID:	1793650  
JohnBuckner is offline  
Reply With Quote
Old 08-20-2012, 02:56 PM
  #7
gphil
Thread Starter
 
Join Date: Oct 2011
Location: Elberton, GA
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Yup you are correct but as mentioned, new at this etc. Also found out that the tank configuration you mentioned is true on my exsisting. So gonna see how much room I really do have in there. I know the battery and rex is up there too and wt / bal come into mind. gphil
gphil is offline  
Reply With Quote
Old 08-20-2012, 03:07 PM
  #8
JohnBuckner
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,323
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Yup I often council those who I am mentoring when needed to slide the battery forward under the tank.

If your included tanks third line hole is unpunctured the go ahead and use the tank if you like.

The number two bulkhead (the one at the wings leading edge ) does not need to be closed off and certainly can be releved within reason (seek a mentor).

John
JohnBuckner is offline  
Reply With Quote
Old 08-27-2012, 01:29 PM
  #9
bullseye000
 
Join Date: Jul 2002
Location: Batavia, IL
Posts: 284
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

I inherited one of these planes in a trade and after leaving it hanging on a wall for years decided to use it for a fun fly. I've been flying it for the last couple of years until the tank finally burst in the fuse. It's one of the early generation of Avistars. I had a hard time finding a tank that would fit in the fuse because the formers were cut to hold the tank which has flat sides and a round top and bottom. With the custom cut formers I thought I was going to have to find a smaller tank to fit into the fuse. Tower has the part listed as "discontinued". I finally found a tank that fit the fuse at Value Hobbies. I don't know how the new ones are but I thought I was going to have to toss the whole airframe because of the fuse design.
bullseye000 is offline  
Reply With Quote
Old 08-27-2012, 04:55 PM
  #10
JohnBuckner
 
JohnBuckner's Avatar
 
Join Date: Dec 2001
Location: Kingman, AZ
Posts: 10,323
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Quote:
ORIGINAL: bullseye000

I finally found a tank that fit the fuse at Value Hobbies. I don't know how the new ones are but I thought I was going to have to toss the whole airframe because of the fuse design.

Bullsye its comments like that that just amaze me and with all due respect to toss an airplane because you cannot find an OEM tank which is more the norm than what you might think, is well its just silly.

I'll bet three burned out glowplugs aginst a stale glazzed donut that all the experianced modelers here could fit an eight or eleven ounce Hayes into your airplane in oh, lets give ourselves time and just say fifteen minutes. A more conventional bung tank would take an extra twenty more minutes or so.

And it would be done properly. There is no reason in the world to not just remove the inside of the bulkheads and use some foam, no reason at all. The easy way is to just use an #11 blade in a handle but short of that use a dremel, chisel, chainsaw or dynamite.

John
JohnBuckner is offline  
Reply With Quote
Old 09-01-2012, 10:29 AM
  #11
bullseye000
 
Join Date: Jul 2002
Location: Batavia, IL
Posts: 284
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank


Quote:
ORIGINAL: JohnBuckner

Quote:
ORIGINAL: bullseye000

I finally found a tank that fit the fuse at Value Hobbies. I don't know how the new ones are but I thought I was going to have to toss the whole airframe because of the fuse design.

Bullsye its comments like that that just amaze me and with all due respect to toss an airplane because you cannot find an OEM tank which is more the norm than what you might think, is well its just silly.

I'll bet three burned out glowplugs aginst a stale glazzed donut that all the experianced modelers here could fit an eight or eleven ounce Hayes into your airplane in oh, lets give ourselves time and just say fifteen minutes. A more conventional bung tank would take an extra twenty more minutes or so.

And it would be done properly. There is no reason in the world to not just remove the inside of the bulkheads and use some foam, no reason at all. The easy way is to just use an #11 blade in a handle but short of that use a dremel, chisel, chainsaw or dynamite.

John
Glad something amazed you. Here's the thing... I probably have more modelling experience than most people posting here. Tower in their infinite wisdom chose to sell an airframe that used an unusual shaped fuel tank with an airframe designed around it. Tower also made the decision to discontinue this part. I was fortunate enough to stumble upon one from a local Chinese importer. As much as I enjoy flying the plane I would have had to find a way to modify 2 formers that were buried in the nose of the plane to get another tank with at least 8oz. into it. Being as the airframe is probably at least 12 years old with 100's of flights on it, sometimes it's better to move long to something else. While you find it silly to toss the airframe, I would have found it even more so to waste the time making modifications to an overused airframe when I could be spending my valuable limited shop time on something better.
bullseye000 is offline  
Reply With Quote
Old 09-01-2012, 01:40 PM
  #12
carrellh
 
carrellh's Avatar
 
Join Date: Mar 2003
Location: Garland, TX
Posts: 6,544
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank

Quote:
ORIGINAL: gphil

Been looking for a fuel tank for the Avastar. Plenty out there but if I remember correctly a 270c/c is the size with only two tubes . The one closet to it has three,,,,,I guess it is an overflow vent ?? Point me to a supplier. I think it has to be one that will only fit this plane. HCAA3747 is a number I saw and wrote down. Ok thanks. gphil
Link to HCAA3747 http://www3.omnimodels.com/cgi-bin/w...I=HCAA3747&P=7
3rd line is for filling without disconnecting from the carb. Keep it plugged if not using.
carrellh is offline  
Reply With Quote
Old 09-02-2012, 06:51 PM
  #13
bullseye000
 
Join Date: Jul 2002
Location: Batavia, IL
Posts: 284
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank


Quote:
ORIGINAL: carrellh

Quote:
ORIGINAL: gphil

Been looking for a fuel tank for the Avastar. Plenty out there but if I remember correctly a 270c/c is the size with only two tubes . The one closet to it has three,,,,,I guess it is an overflow vent ?? Point me to a supplier. I think it has to be one that will only fit this plane. HCAA3747 is a number I saw and wrote down. Ok thanks. gphil
Link to HCAA3747 http://www3.omnimodels.com/cgi-bin/w...I=HCAA3747&P=7
3rd line is for filling without disconnecting from the carb. Keep it plugged if not using.
That looks like the one. The one I bought had some raised lettering and the tank capacity on the side. I had to sand it off to get it into the fuse. It came with two lines, the third being an optional line for filling.
bullseye000 is offline  
Reply With Quote
Old 09-02-2012, 09:41 PM
  #14
Bozarth
 
Join Date: Apr 2004
Location: Aurora, CO
Posts: 1,283
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: Avastar fuel tank


Quote:
ORIGINAL: bullseye000

... I would have had to find a way to modify 2 formers that were buried in the nose of the plane to get another tank with at least 8oz. into it....
Give me two minutes with my dremel and call it done!

Kurt
Bozarth is offline  
Reply With Quote
Reply


Thread Tools
Search this Thread
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -8. The time now is 11:52 PM.