Go Back  RCU Forums > RC Airplanes > Beginners
Reload this Page >

fuel system for cowled airplane

Notices
Beginners Beginners in RC start here for help.

fuel system for cowled airplane

Old 08-20-2008, 08:48 AM
  #1  
jigeye
Thread Starter
 
Join Date: Dec 2005
Location: Germantown, TN
Posts: 542
Likes: 0
Received 0 Likes on 0 Posts
Default fuel system for cowled airplane

I want to set up a fueling system for an airplane with a cowl. I've used a slimline system, however, this caused problems so I want to do it the old fashioned way. Any help from a "schematics" standpoint would be appreciated.
Old 08-20-2008, 08:55 AM
  #2  
RCKen
RCU Forum Manager/Admin
My Feedback: (9)
 
RCKen's Avatar
 
Join Date: Jul 2002
Location: Lawton, OK
Posts: 27,204
Likes: 0
Received 7 Likes on 7 Posts
Default RE: fuel system for cowled airplane

I prefer to use Fuel Dots. They are very easy to set up and are pretty reliable. Use the diaagrams as a guide for setting them up.

Ken
Attached Thumbnails Click image for larger version

Name:	Wu61090.jpg
Views:	10
Size:	40.8 KB
ID:	1015460   Click image for larger version

Name:	Kf12969.jpg
Views:	10
Size:	60.8 KB
ID:	1015461   Click image for larger version

Name:	Qv55255.jpg
Views:	9
Size:	23.9 KB
ID:	1015462   Click image for larger version

Name:	Ey70572.jpg
Views:	13
Size:	32.5 KB
ID:	1015463  
Old 08-20-2008, 10:07 AM
  #3  
brett65
Senior Member
My Feedback: (18)
 
brett65's Avatar
 
Join Date: Dec 2007
Location: Oklahoma City, OK
Posts: 2,505
Likes: 0
Received 0 Likes on 0 Posts
Default RE: fuel system for cowled airplane

Ken, when filling using a fuel dot, will the fuel be forced out through the engine supply line?
Old 08-20-2008, 11:05 AM
  #4  
JohnW
Senior Member
My Feedback: (6)
 
JohnW's Avatar
 
Join Date: Mar 2002
Location: Lincoln, NE
Posts: 1,815
Likes: 0
Received 0 Likes on 0 Posts
Default RE: fuel system for cowled airplane

Brett, with a single fuel/supply line, maybe, but probably not. The pressure in the line may be enough to push past the needles and flood the engine. With a three line setup, the chance is lower, but still there. I've occasionally had issue with some 140-160 YS's flooding from fueling, but it is not common. I resolve it by clamping hemostats on the supply line when fueling. -cheers
Old 08-20-2008, 11:19 AM
  #5  
brett65
Senior Member
My Feedback: (18)
 
brett65's Avatar
 
Join Date: Dec 2007
Location: Oklahoma City, OK
Posts: 2,505
Likes: 0
Received 0 Likes on 0 Posts
Default RE: fuel system for cowled airplane

Does anyone have any good ideas on how to know when the tank is full other than when it starts running out of the muffler. I have seen a section of line running out and back into the cowl that I guess went to the muffler?
Old 08-20-2008, 11:53 AM
  #6  
RCKen
RCU Forum Manager/Admin
My Feedback: (9)
 
RCKen's Avatar
 
Join Date: Jul 2002
Location: Lawton, OK
Posts: 27,204
Likes: 0
Received 7 Likes on 7 Posts
Default RE: fuel system for cowled airplane

brett,
If the carb is closed there is little to no fuel that will get into the carb. If your muffler is pointed downwards the fuel will run out of the muffler when the tank is full. Yes, you will lose a little fuel like this. If you have a place where you can get to the muffler vent line when it's in the cowl then what you can do is split the muffler vent line there, and then rejoin it with a piece of brass tubing. When you are ready to fill the tank pull this line out and split it apart. Now when the tank is full the excess will come out this line and in to a catch bottle if you use one. This works well when the muffer isn't pointed down where excess fuel will drain out through it.

Hope this helps

Ken
Old 08-20-2008, 02:01 PM
  #7  
Stickbuilder
 
Stickbuilder's Avatar
 
Join Date: Nov 2005
Location: Leesburg, FL
Posts: 8,678
Likes: 0
Received 0 Likes on 0 Posts
Default RE: fuel system for cowled airplane


ORIGINAL: brett65

Does anyone have any good ideas on how to know when the tank is full other than when it starts running out of the muffler. I have seen a section of line running out and back into the cowl that I guess went to the muffler?
If you are using a 3 line system, remove the pressure line from the muffler, and fuel through that line, and allow the excess fuel to exit through the vent line (of course you will need to remove the plug from this line first). If you are using a 2 line system, make up another fuel line with a piece of brass tubing inserted into one end. Remove the pressure line from the muffler, attach the extra line above, and route it into a catch container. Then using the fuel dot system that RCKen was talking about, as you fill the tank, the excess will dump out the line to the catch container. Then you put the fuel dot back into the fill hole, disconnect the extension hose, and reattach the pressure line to the muffler.

There are several ways that you can go with fueling the tanks, but just don't expect every model that you have to need to use the same kind or even the same number of lines. For instance, my OS 160 twins can't and won't run with exhaust pressure. I use a 2 line system on them, but in the same plane with a gas engine, I use a 3 line system. One to the carb, one for filling, and a dedicated vent that is attached to a scale fitting. The more you learn, the more you learn.

Bill, AMA 4720
WACO Brotherhood #1
Old 08-23-2008, 03:09 PM
  #8  
jigeye
Thread Starter
 
Join Date: Dec 2005
Location: Germantown, TN
Posts: 542
Likes: 0
Received 0 Likes on 0 Posts
Default RE: fuel system for cowled airplane

Ken,
I was thinking more along these lines. I've photoshoped a pic of the Aeroworks Edge 540T .46-.61 online manual. The white connectors are Sullivan Connectors from Tower. A few questions:

1. Will this work?
2. I had an idea to use a 3 prong for the line from tank to carb that way there would be no disconnecting any lines. Obviously plug it when ready to fly.
3. Regarding the muffler line, once the tank is full would the fuel run out the open connector therefore eliminating fuel going into the muffler or should I just stick to a two prong on the muffler?
Thanks,
M. Ross
Attached Thumbnails Click image for larger version

Name:	Ec88125.jpg
Views:	10
Size:	75.0 KB
ID:	1017475  
Old 08-23-2008, 04:59 PM
  #9  
bigtim
My Feedback: (13)
 
Join Date: May 2004
Location: san francisco, CA
Posts: 4,169
Likes: 0
Received 2 Likes on 2 Posts
Default RE: fuel system for cowled airplane

here is some examples of a fueler location.
the first is the overflow set up jigeye referenced to the line sits in a aluminum bracket I made for my P-40 its connected to a "T" fitting at the pressure line from the muffler, I just pop the plug and fuel exits the line when the tank is full the muffler is fully enclosed in the cowl so there is no access to the pressure line,it prevents the muffler from filling up since it sits quite flat next to the fuse.
second is the set up on my Mustang,the EZ fueler is at the same location as the P-40 mounted to a plywood bracket in the engine area and a small hole in the cowl for the fuel probe to stick through.
the third is located in the fuse of my P-47,I glued the light ply mount to the inside of the fuse sheeting to beef up the area so when pushing or pulling on the fueler there won't be any stress on the area,the P-47 has a pumped engine but it doesn't matter where the fuel dot/fueler is locatedI chose the fuse for cosmetic reasons.
Attached Thumbnails Click image for larger version

Name:	Yw67128.jpg
Views:	15
Size:	34.7 KB
ID:	1017552   Click image for larger version

Name:	Mk25663.jpg
Views:	12
Size:	75.5 KB
ID:	1017553   Click image for larger version

Name:	Vt56896.jpg
Views:	8
Size:	40.0 KB
ID:	1017554  

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


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information

Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.