Matronics Email Lists Forum Index Matronics Email Lists
Web Forum Interface to the Matronics Email Lists
 
 Get Email Distribution Too!Get Email Distribution Too!    FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Fuel return line on Rotax 912ULS - revisited

 
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Zenith701801-List
View previous topic :: View next topic  
Author Message
txpilot



Joined: 26 Feb 2007
Posts: 87
Location: Houston, TX

PostPosted: Thu Oct 22, 2009 6:28 pm    Post subject: Fuel return line on Rotax 912ULS - revisited Reply with quote

I just found out that Rotax has now approved autogas with 10% ethanol for the 912 series engines. Since it seems 100LL will eventually be going away, I have to revisit the question about the fuel return line from the fuel manifold.

I was originally planning on running 100LL on my aircraft so I wasn't concerned about vapor lock issues. Therefore, I never installed the return line suggested by Rotax. However, since it seems the powers-that-be will eventually force us to alternative fuels, I'm wondering if installing this return line for running premium autogas would be a good idea. I just priced the parts needed from Lockwood to install the fuel manifold and it comes to a whopping $514.01.

Am I the only one concerned about this? Is anyone currently running autogas without the return line?

Thanks,

Dan Ginty


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List
Back to top
View user's profile Send private message Send e-mail
Tommy Walker



Joined: 12 Jan 2006
Posts: 442
Location: Anniston, AL 36207

PostPosted: Thu Oct 22, 2009 6:37 pm    Post subject: Re: Fuel return line on Rotax 912ULS - revisited Reply with quote

They are doing away with 100LL?

Dan,

I think that you could plumb the return line back to the gascolator.

You might want to call Zenith and talk to Roger or Caleb.

Tommy Walker in Alabama
Do Not Archive


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List

_________________
Tommy Walker
N25A - Anniston, AL
Back to top
View user's profile Send private message Send e-mail MSN Messenger
craig(at)craigandjean.com
Guest





PostPosted: Fri Oct 23, 2009 6:57 am    Post subject: Fuel return line on Rotax 912ULS - revisited Reply with quote

You can build the equivalent of the official Rotax fuel manifold with parts
from Aircraft Spruce and McMaster-Carr. Look at their multi-port manifolds.
One tricky part is the restrictor on the return line. I think the Rotax
manuals call this out as a 0.030 inch pinhole. I intend to make mine by
filling a brass NPT nipple with solder and drilling a pinhole in it. The
manifold will be mounted vertically and the return line will come off of the
top of the manifold (like the Rotax one) since (as I understand it) in a
vapor lock situation what is being returned is vapor, not liquid fuel.
Another subtle point is that the lines to and from the mechanical fuels pump
have different IDs (1/4 inch in and 5/16ths out?).

On the 701 I won't be trying to return the fuel all the way to the wing
tanks. I'm running the return line to a multi-port manifold (also from
Spruce or McMaster) on the firewall where it will mix with cool fuel coming
from the tanks. I believe this is the way Quality Sport Planes plumbs their
701s.

-- Craig

--


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List
Back to top
dwilde(at)clearwire.net
Guest





PostPosted: Fri Oct 23, 2009 7:58 am    Post subject: Fuel return line on Rotax 912ULS - revisited Reply with quote

t
Quote:
Am I the only one concerned about this? Is anyone currently running autogas without the return line?

Thanks,

Dan Ginty

I have been running premium autogas on my 912S (100HP) for over 90 hours

with no problems and I do not have a return line. I connected the fuel
lines per Zenith firewall forward instructions. All of my fuel lines
are enclosed in firesleeve which should help shield it from high temps.

Dan Wilde
701


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List
Back to top
s.clive.richards(at)homec
Guest





PostPosted: Fri Oct 23, 2009 11:05 am    Post subject: Fuel return line on Rotax 912ULS - revisited Reply with quote

Dan
Here in UK it is mandatory to install the return line to a fuel tank to use
auto gas as per Rotax instructions, but our CAA say we cannot use auto gas
if it contains alcohol unless we are a microlight.
Clive
---


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List
Back to top
txpilot



Joined: 26 Feb 2007
Posts: 87
Location: Houston, TX

PostPosted: Wed Oct 28, 2009 7:22 am    Post subject: Re: Fuel return line on Rotax 912ULS - revisited Reply with quote

Thanks to all who replied. I guess I'll just get my airplane flying as is and worry about the fuel manifold later. Craig -- thanks for the idea of building a manifold. I'll consider that in the future.

Dan


- The Matronics Zenith701801-List Email Forum -
 

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?Zenith701801-List
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    Matronics Email Lists Forum Index -> Zenith701801-List All times are GMT - 8 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group