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boardmant
03-12-2008, 03:36 PM
Anyone have any info about rerouting the fuel lines in a Colt to alleviate the AD, (the placarding) and essentially the inherent problem of fuel starvation. I think the "Miss Pearl" Pacer had it done. Is it worth it? necessary? Also what fuel line do I use? Same that came with Colt? Or this new flexible fuel line? BTW Im doing the O320 STC upgrade if that will change the fuel line size. Many thanks...Tom

Bultaco Jim
03-12-2008, 06:19 PM
Do you need to change the size? My Pacer( O-320 ) has the same size as the Colt's ( O-235 ). Both 3/8 OD. Jim
P.S. I'm asking anybody.

Gilbert Pierce
03-12-2008, 06:50 PM
Here is a link to Ms Pearl's fuel line rerouting 337 that stopped the fuel starvation when manuvering with the right fuel tank.
http://www.shortwing.org/TestSite/index ... File_id=88 (http://www.shortwing.org/TestSite/index.php?module=documents&JAS_DocumentManager_op=downloadFile&JAS_File_id=88)

Eddie Trimmer has an STC to solve the problem.
http://trimmeraviation.com/fuelsys.html

Steve Pierce
03-12-2008, 09:49 PM
The lines for both are 3/8".

sierrasplitter
09-20-2021, 09:53 AM
Can anyone re-post a link
to the Miss Pearl fuel
line re-route ? I want to do this mod on my plane

Gilbert Pierce
09-20-2021, 11:53 AM
It’s not listed on Frank’s web site.http://www.miss-pearl.org/start.html
It was done on a field approval. The link I had to doesn’t work anymore.
Here is what you need as it is STC’d.
http://trimmeraviation.com/fuelsys.html

Update; found a link that works.http://ohio.shortwingpiperclub.org/MaintenanceDataDepot/data/337_FieldApprovals/22_FUEL_LINE2.pdf

Subsonic
09-20-2021, 11:11 PM
Why would anyone do this EXTENSIVE MOD if not doing the seaplane door? Please advise.
-Subsonic

sierrasplitter
09-21-2021, 06:53 AM
So the right tank doesn’t kill you . Thanks for finding that link Gilbert .

Subsonic
09-27-2021, 12:17 PM
So the right tank doesn’t kill you . Thanks for finding that link Gilbert .
If you do go forward with this mod, it would be interesting to see some progress pictures.

shelbysautosales
01-02-2022, 06:33 PM
I did franks mod with new fuel valve that also runs L R and both tanks (Dakota cubs) I did the fuel line to get it out from underneath the dash

Subsonic
01-26-2022, 11:36 PM
Update; found a link that works.http://ohio.shortwingpiperclub.org/MaintenanceDataDepot/data/337_FieldApprovals/22_FUEL_LINE2.pdf

This appears to be a much simpler modification than the Trimmer STC design. It retains the fuel line under the panel. But I don't see where it gets rid of the right tank 1/3 full restriction for take-offs and landings. I believe the Trimmer STC does that.

If you can believe "225% improvement" based upon a right vs. left flow rate differential changing from 18% to 8%,.. I have to assume that's when the fuel valve is in the "both" condition, creating a pressure bias in left vs. right side flow that favors the left tank running dry first. Or maybe there is no "both" on the new valve and that is just a static rate comparison left to right?

My interest is in removing the right tank 1/3 full restriction to avoid "having the right tank kill you" as sierrasplitter puts it.

Also, Would someone with experience in FAA approvals and paperwork kindly comment on how difficult or easy it may be to use/reference this same form OMB No. 2120-0020 as approved data for this mod? Is it as simple as having my IA submit a 337 with this pdf printed out as an attachment?

Thanks,
Subsonic

Subsonic
01-27-2022, 12:13 AM
Also, Frank uses a little hyperbole imo, with his 225% number. If you take his 18% old design vs. 8% mod. design as accurate, that means the right tank originally still held 3.24 gallons when the left tank ran dry. His modification improves the right tank number to only 1.44 gallons remaining when left goes dry. 16.56 gallons/14.76 gallons = 1.122 for a 12.2% net improvement in right tank flow rate. I'd still like to know if that is a static rate difference in right vs. left valve condition or "both" valve condition.

Steve Pierce
01-27-2022, 07:26 AM
I can tell you that the previously approved 337 is acceptable data and can be used to get a field approval for the same modification. It will take either a good relationship with a FSDO inspector or a FSDO inspector with an open mind and a willingness to approve it. They have the authority.

dgapilot
01-27-2022, 09:28 AM
So the right tank doesn’t kill you . Thanks for finding that link Gilbert .

I’ve got lots of PA-22 time and never had an issue with fuel management. The only way it “will kill you” is if the pilot screws up his fuel management. Over 600 hours towing signs with a PA-22-160 where I regularly ran the right tank dry before switching. Never had a problem, just kept my hand on the fuel valve when I was down to the last couple gallons! Always ran the left tank for banner pick ups and drops. Never really did take offs with low fuel as the idea was to fly as many signs before landing (I had 4 hooks on the airplane). After 4 signs, land, fill up, and put 4 more hooks on, repeat! Hours of boredom separated by moments of shear terror! About 2500 hours towing signs over 8 or 10 years.

Back on track, my fuel management strategy in PA-20 and 22 is to start with full fuel and on the right tank and run that dry, then switch to the left so you are on that tank for landing. If landing before depleting fuel in the right side, switch to the left as you enter the pattern. By draining fuel from one side, the more aileron pressure you need reminds you to watch the fuel level and be ready to switch tanks. It does no good to leave any in the right side if you are going for maximum range as you won’t want to be on that tank for landing. Every airplane with a right/left system I’ve flown that way.


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PACERGUY
01-27-2022, 02:33 PM
I agree, on both my old pacer and my cub I simply cough the right tank and go to the left. Never had a problem 1500 hours. DENNY

MichiganPacer
02-17-2022, 11:18 AM
I'm currently installing Trimmer Aviation's fuel system STC. Does anyone have any pictures of how you attached the left rear fuel line to the airframe?
I have MS21919-6 clamps, I'm just not 100% sure that drilling into a frame tube and using a sheetmetal screw is the right thing to do.
Also, I have future plans of installing a Left-hand seaplane door, but I don't have that STC to refer to as far as routing the left rear fuel line so it won't interfere with the door installation. So, helpful suggestions and recommendations are appreciated.
Thank you.

dgapilot
02-17-2022, 12:46 PM
DO NOT drill into tubing! From pictures I've seen of the Trimmer installation, the fuel lines just hang in the breeze, supported by their own rigidity. I'm working with a client now that wants to weld a plate to the lower tubes and substitute bulkhead Ts for the standard T specified in the STC. That at least will provide rigidity for the fuel lines and quick drains.

andya
02-17-2022, 12:58 PM
Steve's Aircraft restored my Pacer and installed the Trimmer fuel mod.
I documented the process as they posted operations the accomplished each week they worked on the plane

https://www.dropbox.com/s/gnzahhk7x31yznk/AndysPacerRestoration-StevesAC-BrianPankonin.pdf?dl=0

This link should take you to a dropbox link to view or download the entire document.
There is probably some pictures and notes of the fuel line routing for that fuel line modification.
There is also pictures of accomplishing the SB819.

mmoyle
02-17-2022, 01:15 PM
https://uploads.tapatalk-cdn.com/20220217/ca8645436c607081c1beabb264e394d3.jpg
https://uploads.tapatalk-cdn.com/20220217/64c6b8f33c2729e9109b57541ab0a26d.jpg
https://uploads.tapatalk-cdn.com/20220217/4178ebfaa8f871154b76bcefbfa9da43.jpg
I’ve added a bit of sheet metal to narrow the door a bit and hide the fuel line with a cover. Shrink tubing where the fuel line might run on the airframe. I’ve seen this tube held in place with fabric when covering the aircraft. If your airplane is covered… You can use screws in the sheet metal formers…not the tube.


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MichiganPacer
03-20-2022, 10:37 AM
Another question, I noticed nobody who reroutes the fuel crossover line to go under the front seats has a rear heat duct under the left front seat. My PA-22/20 has this floor duct and it's directly in the way.
Can I remove it and just placard it inoperable?
I don't plan to have a back seat passenger, or a back seat. That area will mostly be used as cargo space for camping stuff.

mmoyle
03-20-2022, 01:56 PM
https://uploads.tapatalk-cdn.com/20220320/2de14d7acf0f9d9c295c92c5cfd9ee89.jpg
I may add rear heat. My 1950 PA20 wasn’t equipped with rear heat. I’m almost there with the late model split seat installation. Just need to add the firewall box, heat duct tubing and a control cable.


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MichiganPacer
03-20-2022, 08:45 PM
Wow! That looks really nice! My airplane doesn't have carpeting or fabric interior coverings. Seats and headliner are still original from 1959, and it shows.
Interior is a future project. Maybe a couple years down the road. Just Trying to get her flying again for now.
Did you move the battery box to the left side, or is that red and black box something else?

mmoyle
03-20-2022, 10:09 PM
That’s the battery box.


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MichiganPacer
04-11-2022, 12:28 PM
Okay, another dumb question...After all the fuel lines have been rerouted and connections tightened, what is the best way to do a leak check?

Steve Pierce
04-11-2022, 01:04 PM
Pour gas in it is what I have always done, a little at a time.

stevesaircraft(Bri)
04-11-2022, 07:00 PM
Tape off the fuel outlets for the wing tanks, hook up a regulated air source to the gascolator at 1-2 psi.. use soapy water at every fitting and look for bubbles.. I do that before any fabric gets glued on.. I also leave the tape on and plug up the gascolator outlet so no bugs can get in and build a nest..

Brian