Matronics Email Lists :: View topic - Rotax 912 Carb Venting

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

Rotax 912 Carb Venting

Matronics Email Lists Forum Index -> Kitfox-List

View previous topic :: View next topic

Author Message

jablackwell(at)ev1.net
Guest

Posted: Thu Jan 19, 2006 6:01 pm Post subject: Rotax 912 Carb Venting

This has probably been addressed on the list before, so hope the 

old timers will forgive me.  It occured to me that the vent tube 

on the bing carbs present a fire hazard.  Should the float stick 

on either carb, then gasoline would be flowing out of the vent 

tube and on the Kitfox would likely come in contact with the 

exhaust pipes and muffler.  I would not want to be in my Kitfox if 

this happened.



Has there been any instances of a fire because of sticking 

floats?  More importantly, does anyone know of a solution?  Not 

flying is not an option.



Jimmie 



Sent via the EV1 webmail system at mail.ev1.net

rjdaugh(at)rapidnet.com
Guest

Posted: Thu Jan 19, 2006 6:47 pm Post subject: Rotax 912 Carb Venting

Jimmie,

Do you have trays under your carbs?  I was provided two little catch trays

that fit close up under the carbs and are fitted with hose fittings to carry

overflow down and out the cowl.  They are kind of a nuisance at times, but

should do the job.



Randy = Series 5/7  - 912S



.           

--

fordm2003(at)yahoo.com
Guest

Posted: Thu Jan 19, 2006 8:12 pm Post subject: Rotax 912 Carb Venting

Hi Jimmie,



If you don't have trays and you want to re-route the vent lines so the a fuel overflow won't spill onto something hot, you can.  However, these lines are sensative to pressure changes, so you won't want to extend the lines too much.



I think the biggest mistake some poeple have made is to extend the vent lines so that they reach the outside of the cowl.



from: http://www.ultralightnews.com/enginetroublshooting/rotaxtr/trrtx1.htm

"There are two vent tubes located on the side of the Bing         carb. Do not connect any additional hoses to these vents, or vent them outside an enclosed         engine installation. By venting outside the engine cowling you create two different air         pressure areas, that of the outside air, and that of the air inside the engine cowling,         which can effect you fuel mixture."



Mike



 jablackwell <jablackwell(at)ev1.net> wrote: 



This has probably been addressed on the list before, so hope the 

old timers will forgive me.  It occured to me that the vent tube 

on the bing carbs present a fire hazard.  Should the float stick 

on either carb, then gasoline would be flowing out of the vent 

tube and on the Kitfox would likely come in contact with the 

exhaust pipes and muffler.  I would not want to be in my Kitfox if 

this happened.



Has there been any instances of a fire because of sticking 

floats?  More importantly, does anyone know of a solution?  Not 

flying is not an option.



Jimmie 



Sent via the EV1 webmail system at mail.ev1.net

 

                   

 

 

 

		

---------------------------------

 Photo Books. You design it and well bind it!

jdisher(at)intergate.com
Guest

Posted: Fri Jan 20, 2006 8:41 am Post subject: Rotax 912 Carb Venting

Whatever you do, don't tamper with the vent tubes. I increased the 

length on my

left one and the engine dropped two left cylinders on take-off twice 

during the

next 8  times I flew the plane. Really gets your attention. The easiest and

safest solution is to take a small funnel with a longer hose attached, fasten

it up under the carb, and merely lay the vent tube in it, so that if 

fuel drips

out it will be collected by the funnel and drained away from the hot 

exhaust and

you have not upset the balance of the carb.



 	  Quote: 	
		   



 This has probably been addressed on the list before, so hope the

 old timers will forgive me.  It occured to me that the vent tube

 on the bing carbs present a fire hazard.  Should the float stick

 on either carb, then gasoline would be flowing out of the vent

 tube and on the Kitfox would likely come in contact with the

 exhaust pipes and muffler.  I would not want to be in my Kitfox if

 this happened.



 Has there been any instances of a fire because of sticking

 floats?  More importantly, does anyone know of a solution?  Not

 flying is not an option.



 Jimmie



 Sent via the EV1 webmail system at mail.ev1.net

aerocontrols(at)clearwave
Guest

Posted: Fri Jan 20, 2006 10:33 am Post subject: Rotax 912 Carb Venting

Jimmy,

There are drip trays available that fit under the carbs.. I know of no

fires resulting from overflowing carburetors.

One thing you do not want to do is extend the vent lines and move them away

from the carburetors.  This changes the pressure in the float bowls

resulting is mixture changes...



regards

Bob Robertson

Light Engine Services Ltd.

Rotax Service Center

Aero Control Enterprises, Inc.

St. Albert, Ab. T8N 1M8

Ph: (Tech Support) 1-780-418-4164

Ph: (Order Line) 1-866-418-4164 (TOLL FREE)

www.rtx-av-engines.ca

www.aerocontrols.net

---

rwill1(at)adelphia.net
Guest

Posted: Fri Jan 20, 2006 2:02 pm Post subject: Rotax 912 Carb Venting

Bob,

Is there a "recommended" length for the vent tubes to extend?

jablackwell(at)ev1.net
Guest

Posted: Fri Jan 20, 2006 3:36 pm Post subject: Rotax 912 Carb Venting

No trays with mine. Trays sound like the answer to my concerns.  

Anyone know where to get them?



Jimmie



--------

aerocontrols(at)clearwave
Guest

Posted: Fri Jan 20, 2006 4:07 pm Post subject: Rotax 912 Carb Venting

Jimmy,

I will ceheck to see what is hanging around is the used parts dept.  Will

e-mail you Monday.  Maybe someone has some they could part with.



regards

Bob Robertson

Light Engine Services Ltd.

Rotax Service Center

Aero Control Enterprises, Inc.

St. Albert, Ab. T8N 1M8

Ph: (Tech Support) 1-780-418-4164

Ph: (Order Line) 1-866-418-4164 (TOLL FREE)

www.rtx-av-engines.ca

www.aerocontrols.net

---

pwmac(at)sisna.com
Guest

Posted: Fri Jan 20, 2006 5:20 pm Post subject: Rotax 912 Carb Venting

Trays come with the 914 and can be purchased seperately



A Rotax guy told me to leave the plastic tube where it was from the factory 

and put a Tee on its end then run a longer tube to the  cowl bottom. Didn't 

do it, but it is an interesting thought.

  Paul

===================



At 03:31 PM 1/20/2006, you wrote:

[quote]

No trays with mine. Trays sound like the answer to my concerns.

Anyone know where to get them?



Jimmie



--------

lcfitt(at)sbcglobal.net
Guest

Posted: Fri Jan 20, 2006 6:08 pm Post subject: Rotax 912 Carb Venting

California Power Systems has them:



http://www.800-airwolf.com/



Click on online store, then click on search.  You are looking for carb pans



Lowell



---

aerocontrols(at)clearwave
Guest

Posted: Sat Jan 21, 2006 8:45 am Post subject: Rotax 912 Carb Venting

Rick,

The lines as they are shipped from the factory are 120mm (a tad longer than

4 3/4").

Thats what I'd stay with.  Differences in cowling pressures and temperatures

between airplanes

could make a difference in air pressure in the float bowl. Therefore any

changes to where the float bowl chambers tubes are placed could result in a

dramatic change.



Hope this helps



Bob R



---

jablackwell(at)ev1.net
Guest

Posted: Sun Jan 22, 2006 5:42 pm Post subject: Rotax 912 Carb Venting

Just a note to say thanks for all the input on 912 carb venting.  

You all sure gave me a lot to think about.  



Currently, I am in the process of changing my engine mount shock 

pads.  This is one heck of a chore.  Anyone contemplating doing 

this may want to contact me and perhaps I can save  you some 

pain.  So far, I have removed the exhaust system and most of the 

coolant lines. I was surprised to find that even after 11 years 

and 340 engine hours the pads are in good condition.  They look 

bad on the surface, but when I took them out of the mounts they 

are ok except a very thin layer of deteriation on the surface.  I 

am changing them anyway since I have them apart.



Anyone know how long these things can last?



Jimmie

--------

KITFOXPILOT(at)msn.com
Guest

Posted: Sun Jan 22, 2006 6:21 pm Post subject: Rotax 912 Carb Venting

DON'T KNOW OW LONG THEY LAST, BUT I ALSO CHANGED MINE, WHAT A JOB.



Ray

  ---

cliffh(at)outdrs.net
Guest

Posted: Sun Jan 22, 2006 7:02 pm Post subject: Rotax 912 Carb Venting

If I remember correctly, Skystar recomminded that they be changed annually.

Floran H.

---

Display posts from previous:

	Matronics Email Lists Forum Index -> Kitfox-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