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I finally flew it!

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d-m-hague(at)COMCAST.NET
Guest

Posted: Sun Sep 23, 2007 5:46 pm Post subject: I finally flew it!

Patience is rewarded and I finally flew my Ultrastar today!  (I don't count 

yesterday's short crow hop as a flight).  My only complaint is that it was 

too short... as soon as I was high enough to be committed, the engine 

started surging.  Fortunately I only had to climb a little to be high 

enough to make the sod farms south of the airport, then throttling back 

smoothed things out a bit, keeping me aloft in a slow descent.  Gave me 

enough to go around and get it back to the runway... made a real fast steep 

approach since I didn't have the opportunity to feel it out and do a few 

stalls as I'd planned.  Got it down OK though, my only complaint is that I 

can't even say how it handled (except that it was no trouble), in that 

situation you just "do it" without thinking about it.



Turns out there was an air leak at the fuel filter, which I at first 

attributed to the cheap worm screw hose clamps that were on the plane when 

I bought it.  However, after removing them, trimming the lines, and 

securing them with several wraps of safety wire, I still get air bubbles 

and little fuel in the filter at full power (on the ground, of course!)  As 

it got dark I didn't have time to investigate further; I'm wondering if the 

filter itself (the clear plastic one with the sintered bronze element that 

Aircraft Spruce sells for ultralights) maybe has a leak, perhaps a bad 

plastic weld... anybody ever heard of such a thing?



With luck I'll be able to get new clamps and filter on tomorrow after work, 

and squeeze in a longer flight before sunset.



				-Dana

--

--

"I'm a lawyer." "Honest?" "No, the usual kind."

jindoguy(at)gmail.com
Guest

Posted: Sun Sep 23, 2007 6:14 pm Post subject: I finally flew it!

Dana, Easy enough to check the seam on the filter for leaks, just smear a coating of wheel bearing grease around the seam and see if the bubbles go away. Old Harley trick to check for intake leaks.



Rick



 On 9/23/07, Dana Hague <d-m-hague(at)comcast.net (d-m-hague(at)comcast.net)> wrote: 	  Quote: 	
		   --> Kolb-List message posted by: Dana Hague <d-m-hague(at)comcast.net (d-m-hague(at)comcast.net)>



Patience is rewarded and I finally flew my Ultrastar today!  (I don't count

yesterday's short crow hop as a flight).  My only complaint is that it was 

too short... as soon as I was high enough to be committed, the engine

started surging.  Fortunately I only had to climb a little to be high

enough to make the sod farms south of the airport, then throttling back 

smoothed things out a bit, keeping me aloft in a slow descent.  Gave me

enough to go around and get it back to the runway... made a real fast steep

approach since I didn't have the opportunity to feel it out and do a few 

stalls as I'd planned.  Got it down OK though, my only complaint is that I

can't even say how it handled (except that it was no trouble), in that

situation you just "do it" without thinking about it. 



Turns out there was an air leak at the fuel filter, which I at first

attributed to the cheap worm screw hose clamps that were on the plane when

I bought it.  However, after removing them, trimming the lines, and 

securing them with several wraps of safety wire, I still get air bubbles

and little fuel in the filter at full power (on the ground, of course!)  As

it got dark I didn't have time to investigate further; I'm wondering if the 

filter itself (the clear plastic one with the sintered bronze element that

Aircraft Spruce sells for ultralights) maybe has a leak, perhaps a bad

plastic weld... anybody ever heard of such a thing?



With luck I'll be able to get new clamps and filter on tomorrow after work, 



	


-- 

Rick Girard

"Ya'll drop on in"

takes on a whole new meaning

when you live at the airport.  [quote][b]

d-m-hague(at)comcast.net
Guest

Posted: Sun Sep 23, 2007 6:24 pm Post subject: I finally flew it!

At 10:14 PM 9/23/2007, Richard Girard wrote:

 	  Quote: 	
		  Dana, Easy enough to check the seam on the filter for leaks, just smear a 

coating of wheel bearing grease around the seam and see if the bubbles go 

away. Old Harley trick to check for intake leaks.


	


Good idea, thanks, I'll try that... I'm going to replace it anyway, filters 

are cheap, but it's nice to know for sure.



                                 -Dana

--

--

"I'm a lawyer." "Honest?" "No, the usual kind."

d-m-hague(at)comcast.net
Guest

Posted: Sun Sep 23, 2007 6:31 pm Post subject: I finally flew it!

Oh yeah... a few pix at

http://smg.photobucket.com/albums/v486/flyparafan/Kolb/



Note the gap seal too, since we're having that discussion...



				-Dana

--

--

"I'm a lawyer." "Honest?" "No, the usual kind."

wenquist(at)comcast.net (
Guest

Posted: Mon Sep 24, 2007 4:56 pm Post subject: I finally flew it!

If you have a bing carb the surge problem may be within.  Open the top end of the carb and check 

 whether or not the e-clip on the jet needle is placed on the wrong side (above or below) of the spring cup.  If the e-clip is on the wrong side the engine will surge erratically at higher rpm.  

  

 -------------- Original message -------------- 

From: Dana Hague <d-m-hague(at)COMCAST.NET> 



[quote] --> Kolb-List message posted by: Dana Hague 

 

 Patience is rewarded and I finally flew my Ultrastar today! (I don't count 

 yesterday's short crow hop as a flight). My only complaint is that it was 

 too short... as soon as I was high enough to be committed, the engine 

 started surging. Fortunately I only had to climb a little to be high 

 enough to make the sod farms south of the airport, then throttling back 

 smoothed things out a bit, keeping me aloft in a slow descent. Gave me 

 enough to go around and get it back to the runway... made a real fast steep 

 approach since I didn't have the opportunity to feel it out and do a few 

 stalls as I'd planned. Got it down OK though, my only complaint is that I 

 can't even say how it handled (except that it was n  o trou ble), in that 

 situation you just "do it" without thinking about it. 

 

 Turns out there was an air leak at the fuel filter, which I at first 

 attributed to the cheap worm screw hose clamps that were on the plane when 

 I bought it. However, after removing them, trimming the lines, and 

 securing them with several wraps of safety wire, I still get air bubbles 

 and little fuel in the filter at full power (on the ground, of course!) As 

 it got dark I didn't have time to investigate further; I'm wondering if the 

 filter itself (the clear plastic one with the sintered bronze element that 

 Aircraft Spruce sells for ultralights) maybe has a leak, perhaps a bad 

 plastic weld... anybody ever heard of such a thing? 

 

 With luck I'll be able to get new clamps and filter on tomorrow after work, 

 and squeeze in a longer flight before sunset. 

 

 -Dana 

 -- 

&  gt; --   	  Quote: 	
		  [b]

d-m-hague(at)comcast.net
Guest

Posted: Mon Sep 24, 2007 5:21 pm Post subject: I finally flew it!

At 08:56 PM 9/24/2007, Walt Enquist wrote:

 	  Quote: 	
		  If you have a bing carb the surge problem may be within.  Open the top end 

of the carb and check whether or not the e-clip on the jet needle is 

placed on the wrong side (above or below) of the spring cup.  If the 

e-clip is on the wrong side the engine will surge erratically at higher rpm.


	


Thanks Walt, it was definitely an air leak (and it's a Mikuni carb 

anyway).  The problem appears to have been a bad (new out of the box from 

Aircraft Spruce) primer bulb.  It didn't look that way as the bubbles 

appeared at the filter, but replacing both the [also new] filter and hose 

clamps didn't solve it.  Putting the original primer bulb back on solved 

the problem.  I haven't disassembled the suspect bulb yet, but it looks 

like it was restricting fuel flow, so the pump was able to generate enough 

suction to pull air in anywhere it could, even though tightly clamped.



With the problem fixed I enjoyed a beautiful 1/2 hour flight tonight.



                                 -Dana

--

--

"I'm a lawyer." "Honest?" "No, the usual kind."

lcottrell

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

Posted: Mon Sep 24, 2007 5:50 pm Post subject: I finally flew it!

).  The problem appears to have been a bad (new out of the box from

 	  Quote: 	
		   Aircraft Spruce) primer bulb.


	




That is the second primer bulb from ACS that was defective out of the box. 

That is just the few people on this list, and there are two of them. Wonder 

if the whole batch is defective.

Larry C

do not archive

_________________
do not archive

Thom Riddle

Joined: 10 Jan 2006
Posts: 1597
Location: Buffalo, NY, USA (9G0)

Posted: Tue Sep 25, 2007 3:56 am Post subject: Re: I finally flew it!

Dana,



I've very glad to hear you flew without the fuel starvation problem.  



The following is my 2 cents worth on primer bulbs. 



Most of the primer bulb installations I've seen are either in parallel or series with the pulse pump and therefore are being used only as a hand pump to fill the float bowl. Why so many do it this way is a mystery to me since the purpose of the PRIMER is to give a little squirt of fuel into the throat of the carburetor for a quick start. Having it plumbed (either parallel or series) to the float bowl does not accomplish this.



When I bought my Firestar it had no primer at all and took many many pulls to get it started with the proper starting technique with the float bowl full. I bought a high quality PRIMER bulb from West Marine and installed it ACCORDING TO THE ROTAX MANUAL, which means it is teed off of the fuel supply line before the pulse pump (between tank and pump)  and then goes to the primer fitting on the carburetor, which is downstream of the venturi and butterfly valve. I also installed a shutoff valve between the tee and the primer bulb to prevent the pulse pump from sucking air if the check valve in the primer fails. 



When starting cold, I open the shutoff valve, give the bulb one squeeze (squirting a bit of raw fuel into the throat of the carburetor), shut off the valve, and pull the starter rope once and it starts. The whole purpose of a primer bulb is to get a squirt of raw fuel into the intake so it will start on a single pull when cold. Once it is running, the pulse pump quickly fills the float bowl if it was low due to evaporation from sitting for a while. The primer bulb's primary purpose is NOT to fill the float bowl which is all it will do if it is plumbed the way most folks do it, contrary to the Rotax manual. Having the primer bulb in the fuel system feeding the float bowl creates another point of potential failure, which it sounds like maybe was the problem you had. If the primer bulb is plumbed into the primer fitting on the carburetor and isolated with a shutoff valve, it is not part of the fuel supply system when running.



Attached is a photo of the 2-stroke installation manual figure showing the primer installation schematic. It shows a plunger type primer which does not need a shut-off valve but the bulb type should have a shut-off valve to isolate it in case of check valve failure.

primer.jpg

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_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

d-m-hague(at)comcast.net
Guest

Posted: Tue Sep 25, 2007 9:06 am Post subject: I finally flew it!

At 07:57 AM 9/25/2007, Thom Riddle wrote:

 	  Quote: 	
		  



... the purpose of the PRIMER is to give a little squirt of fuel into the 

throat of the carburetor for a quick start. Having it plumbed (either 

parallel or series) to the float bowl does not accomplish this.... The 

primer bulb's primary purpose is NOT to fill the float bowl which is all 

it will do if it is plumbed the way most folks do it...


	


Makes sense.  On my engine (Cuyuna, with Mikuni carb), there is no primer 

port, but there is a choke lever.  Cold, it will start on the first pull 

with the choke on.  Between flights, if everything is sealed well (it seems 

to be, now), the fuel line should stay full, but if not (or at initial 

startup), it could take an awful lot of cranking to fill the fuel system up 

to and including the float bowl.



I had considered tee-ing in a bypass around the primer bulb with a couple 

of check valves, but that just adds more complication and more potential 

leak points.  I also considered putting in a primer hole and adding a 

plunger type primer, deleting the bulb, and using the plunger primer to 

pull fuel up if necessary... but it'd still need a check valve to keep from 

pulling fuel (or air) back from the carburetor if the float needle is open.



One option for priming could be a tee off the fuel line downstream of the 

bulb, with a valve, so that when you open that valve the bulb would force 

fuel into the carburetor throat, but with the valve closed it'd still be 

able to fill the fuel line and bowl.



As for putting the bulb series or parallel to the pulse pump, I guess it's 

a matter of which do you think is more likely-- the bulb leaking or getting 

blocked?



Just random thoughts... not sure which direction I want to go.



                         -Dana

--

--

"I'm a lawyer." "Honest?" "No, the usual kind."

Thom Riddle

Joined: 10 Jan 2006
Posts: 1597
Location: Buffalo, NY, USA (9G0)

Posted: Tue Sep 25, 2007 9:39 am Post subject: Re: I finally flew it!

Dana,



If you have a squeeze bulb in place to fill the float bowl, then adding a tee and shut-off valve to prime the carb too, that would satisfy both requirements. 



The parallel/series debate has been beat to death. But for what it's worth, Standard Category Type Certificated aircraft put auxiliary fuel pumps (which a squeeze bulb is in this case) in parallel with the primary pump, but these are invariably very reliable electric pumps, not squeeze bulbs. This provides an alternate path for the fuel in case the primary pump becomes blocked or otherwise fails. That said, our Special LSA Allegro (factory built) has the aux. electric in series with the mechanical engine driven pump, but this is done to avoid the rather difficult plumbing problem that would result if piped in parallel.



do not archive

_________________
Thom Riddle
Buffalo, NY (9G0)

Don't worry about old age... it doesn't last very long.
- Anonymous

russ(at)rkiphoto.com
Guest

Posted: Tue Sep 25, 2007 11:50 am Post subject: I finally flew it!

FWIT, when I put the 180hp conversion  on my  170; it required an  

electric fuel pump in series with the engine-driven mechanical pump.  

This in addition to gravity-feed; which in  high-wing Cessnas  ( at  

least in normal flight attitudes) is all you normally would ever need.

Original engine (Continental 0-300) had a single mechanical fuel pump  

on the engine. Don't know why they added the electric pump for the  

180 conversion.

Must have found some weird maneuver that required more fuel -- or  

someone's brother-in-law sells fuel pumps.

Never saw or heard of a fuel filter bypass. This DAR sounds ???

do not archive



On Sep 25, 2007, at 1:40 PM, Thom Riddle wrote:



 	  Quote: 	
		   



 Dana,



 If you have a squeeze bulb in place to fill the float bowl, then  

 adding a tee and shut-off valve to prime the carb too, that would  

 satisfy both requirements.



 The parallel/series debate has been beat to death. But for what  

 it's worth, Standard Category Type Certificated aircraft put  

 auxiliary fuel pumps (which a squeeze bulb is in this case) in  

 parallel with the primary pump, but these are invariably very  

 reliable electric pumps, not squeeze bulbs. This provides an  

 alternate path for the fuel in case the primary pump becomes  

 blocked or otherwise fails. That said, our Special LSA Allegro  

 (factory built) has the aux. electric in series with the mechanical  

 engine driven pump, but this is done to avoid the rather difficult  

 plumbing problem that would result if piped in parallel.



 do not archive



 --------

 Thom in Buffalo

 N221FA Allegro 2000 912UL

 N197BG FS1/447

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

 &quot;Setting an example is not the main means of influencing  

 another, it is the only means.&quot;

 Albert Einstein





 Read this topic online here:



 http://forums.matronics.com/viewtopic.php?p=136374#136374

planecrazzzy
Guest

Posted: Tue Sep 25, 2007 2:31 pm Post subject: Re: I finally flew it!

Here's a picture of my primer bulb "By-pass"



Just close the valve , squeeze the bulb , then open the valve...



Gotta Fly...

 Mike & "Jaz" in MN

Squeeze bulb bypass valve 003.jpg

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