Matronics Email Lists :: View topic - fuel problem I think?

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

fuel problem I think?

Matronics Email Lists Forum Index -> Kolb-List

View previous topic :: View next topic

Author Message

Arksey(at)aol.com
Guest

Posted: Fri Jul 06, 2007 4:33 pm Post subject: fuel problem I think?

Hello gang, 

Looking for information and advice. We have a firestar ll with a 503  rotax, 

dual ignition, dual carbs, pull start, no battery, Grandson experienced a  

engine problem which is described as engine rpmâ€™s dropped off , engine was not  

running rough nor sounded or felt rough when rpm dropped, engine rpms came 

right  back up without engine stopping. He had been airborne about 5 minutes when 

this  happened,  He came back in and  landed and the engine ran ok after the 

problem.  We checked things over, pulled the carb  bowls and things looked ok. 

He took off and flew about a hour with no engine  problem. I later flew about 

a hour with no problem. A few days later I decided  to take a little pitch out 

of prop to gain more rpmâ€™s on take off and after  warming up engine and 

testing mags I took off to experience the same problem he  had, but i was at about 

300â€™ , Rpmâ€™s dropped a lot to the point I thought it was  going to quit. It 

did this about 3 times before I got in back on the runway. It  acted to me like 

the engine was running out of fuel and then would get enough  fuel to run ok. 

I checked everything out found nothing wrong and decided to take  off again. 

Engine again had same problemâ€¦Just like prior takeoff. This convinced  me to 

put it in the hangar and fix the problem.  The fuel system is described as 

follows.  I have all nearly new gas lines, plastic, and recommended type, heavy 

type pulse  line. Pulse pump was rebuilt about 40 hours ago, , gascolater screen 

is clean ,  fuel filter with about  20 hours. Primer bulb was new this  

spring and has bypass , also a primer in the system.  Fuel comes out of the bottom 

of 2  5gal tanks. Tank filler caps are  vented.  We are fussy about our fuel  

and it goes thru a mr funnel when filling the tanks. Carbs rebuilt about 30  

hours ago.  I have found nothing  wrong from inspection except the pulse pump 

has no weep hole as recommended,  also pulse line does not go below pump to 

form trap as recommended. So we are  going to put on new pump with weep hole and 

correct the pulse line, new fuel  filter and  test fly it.   I wonder about 

this also: the  pulse pump is about 31â€ about the bottom of the tanks and the 

length of pulse  line is 12â€ long.  Pump specs call  for maximum rise of 39â€.So 

we are close to the maximumâ€¦I am considering  a electric fuel pump running 

off the  engine electrity, not battery and being plumbed in series, not 

parallel. I know  that some recommend the electric pump be installed in parallel, but 

this is a  lot more complicated and messyâ€¦.and is it really necessary?? Sorry 

for such a  long postâ€¦.but thanks for your thoughts and inputâ€¦will let you 

know what  happens. 

Jim  Swan  firestar ll 503    michigan

 



************************************** See what's free at http://www.aol.com

planecrazzzy
Guest

Posted: Fri Jul 06, 2007 5:01 pm Post subject: Re: fuel problem I think?

It sounds like slight "Carb Ice" to me.....



 I had it happen with a 582.....a few years ago....Had to land



Later my Dad told me that I should have tried to hit the Primer...

               Gotta Fly...

                                Mike & "Jaz" in MN - FSII/503

jlsk1(at)frontiernet.net
Guest

Posted: Fri Jul 06, 2007 5:07 pm Post subject: fuel problem I think?

Jim, ask yourself, What changed with the plane since your last  uneventful flights, did you add fuel? if so, check the source/Quality. In other  words, I think that your plan you mentioned in the post is the correct course of  action.. Can you extend the fuel hose from the carb, , route the hose extension  from there back to a fuel can on the ground under the plane & see if you can  get the fuel to siphon back close to the ground? If so, it's probably not the  fuel system/& or clogged filter.

 How about the  jetting, ? small piece of dirt that gets  released when RPMs/suction drop? & so on. Like I said, I think you`re on the  right track already.   Jim

  

 ---

beauford173(at)verizon.ne
Guest

Posted: Fri Jul 06, 2007 5:18 pm Post subject: fuel problem I think?

Jim:

 Whatever else you check, if it were mine, I'd sure be wanting  to yank the exhaust manifold off and look at the pistons and rings for signs of  scuffing and possible near-seizure...  Had similar symptoms with my Nazi  447once... was carboned-up rings which caused it to almost seize. It bogged  down, then recovered for a while and ran normally... I flew on home and cleaned  the fuel system...Started it cold and it ran OK... on takeoff it bogged  again...  I looked into the exhaust ports and instantly saw the  problem.  I was lucky -- got off with new pistons and a carbuerator choke  piston...  Could have easily cost me my fanny.

  

  Just a thought....Worth what ye paid fer  it...

  

 Beauford

 Firefly 076 / N173BW

 Brandon, FL

 [quote]   ---

Arksey(at)aol.com
Guest

Posted: Fri Jul 06, 2007 6:05 pm Post subject: fuel problem I think?

Hi mike,

     thanks for your suggestion of carb ice...but  conditons were not conducive for carb ice at time......but yes it is  possible....thanks Mike....

  

 jim swan firestar ll michigan



See what's free at AOL.com. 

  [quote][b]

Arksey(at)aol.com
Guest

Posted: Fri Jul 06, 2007 6:10 pm Post subject: fuel problem I think?

Hi JIm,

    thanks...yur idea about siphon fuel back to a  can  is a good way to check resistance in fuel  line....thanks....

  

 jim swan firestar ll 503  michigan



See what's free at AOL.com. 

  [quote][b]

Arksey(at)aol.com
Guest

Posted: Fri Jul 06, 2007 6:12 pm Post subject: fuel problem I think?

Hi Beauford.

   thanks.... will check pistons...good thought.....jim swan  firestar ll 503 michigan

  



See what's free at AOL.com. 

  [quote][b]

ElleryWeld(at)aol.com
Guest

Posted: Fri Jul 06, 2007 7:01 pm Post subject: fuel problem I think?

one other thing you might try is pulling the slides out of your carbs and raising the needle one notch,  usually I do this in the spring of the year  but I didnt this year and ended up doing it later to make my engine purr again  as soon as it started running like that I knew what it was and landed at the next strip and made the proper adjustment 

 

 Just another thought  from Maine 

 

 Ellery

 

 Do Not Archive

**************************************

 See what's free at http://www.aol.com.  [quote][b]

WhiskeyVictor36(at)aol.co
Guest

Posted: Fri Jul 06, 2007 7:26 pm Post subject: fuel problem I think?

In a message dated 7/6/2007 11:02:20 P.M. Eastern Daylight Time,  ElleryWeld(at)aol.com writes:

  	  Quote: 	
		  you    might try is pulling the slides out of your carbs and raising the needle one    notch,  usually I do this in the spring of the year   	


 

 Ellery,

  

 Do you mean raise the needle, by lowering the clip in the groove?

  

 If so, that would allow more fuel mix (richer).  I thought it was  better to lean out for the summer because there's less air due to humidity.   

 Bill  Varnes

Original Kolb FireStar

Audubon NJ

Do Not  Archive





See what's free at AOL.com. 

  [quote][b]

lcottrell

Joined: 29 May 2006
Posts: 1494
Location: Jordan Valley, Or

Posted: Fri Jul 06, 2007 8:05 pm Post subject: fuel problem I think?

Check the squeeze bulb.

 Larry C

 [quote]   ---

aoldman(at)xtra.co.nz
Guest

Posted: Fri Jul 06, 2007 10:53 pm Post subject: fuel problem I think?

Have had similar problem , the problem was the air  filter. Take the air filter off and see if RPMs come back to normal. If they do  give the filter a good clean . The method I use is hot soapy water and then  dry out .I find this needs done about every 25 to 30 hours to prevent  occurrence  If its fuel starvation that will not help but pulling the chock  on when the problem occurs will or should momentarily rectify the problem and  point you in the right direction.

  

   Tony

 [quote]   ---

pj.ladd(at)btinternet.com
Guest

Posted: Fri Jul 06, 2007 11:02 pm Post subject: fuel problem I think?

Looking for information and  advice>>

  

 Whats the weather like?  Carb  ice?

  

 Pat

   [quote][b]

planecrazzzy
Guest

Posted: Sat Jul 07, 2007 2:58 am Post subject: Re: fuel problem I think?

You can get Carb Ice at 70 degree F.....if the humidity is up.....



Gotta Fly...

Mike & "Jaz" in MN

.

.

.

[/quote]



 

 	  Quote: 	
		  Whats the weather like? Carb ice? 



Pat

ElleryWeld(at)aol.com
Guest

Posted: Sat Jul 07, 2007 4:44 am Post subject: fuel problem I think?

Yes Bill that is what I have to do every year in the warm weather to make my machine run good  or it will act like it is running out of fuel  in short spirts but never completly quits  when it happens it will make you look real fast for a landing spot 

 

 Ellery 

 do not archive

**************************************

 See what's free at http://www.aol.com.  [quote][b]

George Myers

Joined: 10 Jan 2006
Posts: 76
Location: San Marcos, Texas

Posted: Sat Jul 07, 2007 9:58 am Post subject: fuel problem I think?

I had the same problem with a 503 on a quicksilver a couple years ago that I got a good deal on. Tried 3 different carbs, dozens of settings, 3 different fuel pumps, all new fuel lines & filter and a thunderbird dance. It would give 6000 rpms for 2 to 5 minutes then cut back to 1500 to 2000 for about the same. I could stay up with good thermals but not for too long otherwise. Finally pulled the jugs off. The rings were stuck just a little (if there is such a thing) and there were a couple light scuff marks on both pistons. Also the crosshatching on the cylinder walls was negligible to nonexistent. I purchased the next sized up pistons & rings online, had a local machine shop bore the walls to spec & it flew like a new one until I sold it 200 hours later. I assumed then, & still do, that it was partially seizing until it cooled a little then was good to go until it heated up again. I put about 6 or 8 hours & several â€˜excitingâ€™ flights on it that way.   

George  

   

         

From: owner-kolb-list-server(at)matronics.com [mailto:owner-kolb-list-server(at)matronics.com] On Behalf Of Arksey(at)aol.com

 Sent: Friday, July 06, 2007 7:33 PM

 To: kolb-list(at)matronics.com

 Subject: fuel problem I think?  

  

  

     

Hello gang,  

Â Â  Looking for information and advice. We have a firestar ll with a 503 rotax, dual ignition, dual carbs, pull start, no battery, Grandson experienced a engine problem which is described as engine rpmâ€™s dropped off , engine was plumbed in series, not parallel. I know that some recommend the electric pump be installed in parallel, but this is a lot more complicated and messyâ€¦.and is it really necessary?? Sorry for such a long postâ€¦.but thanks for your thoughts and inputâ€¦will let you know what happens.  

   

Jim SwanÂ  firestar ll 503Â Â Â  michigan  

    

   

  



 

         

  

See what's free at AOL.com.   

   	  Quote: 	
		    http://www.matronics.com/Navigator?Kolb-List 	
0 	  Quote: 	
		   	
1 	  Quote: 	
		   	
2 	  Quote: 	
		   	
3 	  Quote: 	
		   	
4

  

       [quote][b]

Display posts from previous:

	Matronics Email Lists Forum Index -> Kolb-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