I am helping a friend return an out of service ragwing to airworthiness. This one, like a lot of ragwings, had the fuel pump removed a long time ago. We have been hearing that the FAA now wants to see that these are back on, since it was required as original equipment. Any suggestions on how to best accomplish this would be greatly appreciated. I expect there is not just the pump, but fuel lines to be fabricated, etc.
We would appreciate any advice. This time we need to do it not just right, but legally.
Right now, it makes me appreciate my own A model...
Thanks for the help!
re-installing ragwing fuel pump?
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
re-installing ragwing fuel pump?
Glenn
'50 170A N5493C
'50 170A N5493C
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zero.one.victor
- Posts: 2271
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The first quarter 1999 170 News has an article by Assn member Tom Arsenault about reinstallation of the mechanical fuel pump on his ragwing.It was apparently a spendy & exasperating project.
The third quarter 1999 170 News has an article by member Duane Shockey about the installation of an electric fuel pump on his '48.
I briefly considered doing the electric pump conversion when I had my engine overhauled last year.It sounded like it'd be a better,cleaner way to do what apparently isn't really needed--lotsa ragwings out there with just gravity-feed---except according to the type certificate. But I decided that the old saying "if it ain't broke,don't fix it" applied,so I didn't.
Eric
The third quarter 1999 170 News has an article by member Duane Shockey about the installation of an electric fuel pump on his '48.
I briefly considered doing the electric pump conversion when I had my engine overhauled last year.It sounded like it'd be a better,cleaner way to do what apparently isn't really needed--lotsa ragwings out there with just gravity-feed---except according to the type certificate. But I decided that the old saying "if it ain't broke,don't fix it" applied,so I didn't.
Eric
Regaurding your fuel pump problem I went through the same thing a while back. You will need a check valve. The system is designed to gravity feed if your pump fails so you need to by-pass the pump with a line and checkvalve INSTALLED IN THE PROPER DIRECTION. If you put the valve in backward you may not know it until your pump fails and you will be looking for the closest field even if none are available!!! Do not use the part # in the maintnance handbook published by the association as it requires to much pressure to open and gravity fuel pressure will not open it. I sent the republic part # Cessna recomended to me, to Velvet about 2 years ago and it was published in the quarterly magazine so she may be able to help you there. You will also need a fuel pressure gauge for your panel so you can tell if the pump is working. Duane Shockley in CA has gotten a 337 to replace the mechanical pump with an electric pump to be use I believe on takeoff and landing. This mod keeps the system cleaner as you do not have to run the lines to the front of the engine which was a real pain on my set up. A copy of his work is available from headquarters also. Although I would not recommend it my pump was removed when I bought my plane and I flew it for a while with out any problems. Before fixing the problem I tried to create conditions where it would cause a problem at altitude over the airport Even in power on stalls the engine never quit. But I must admit I feel better with the pump on even if I dont worry about it failing. Bill K
Polished 48 170 Cat 22 JD 620 & Pug
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zero.one.victor
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- Joined: Tue Apr 23, 2002 12:11 am
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zero.one.victor
- Posts: 2271
- Joined: Tue Apr 23, 2002 12:11 am
I had occasion last year to pull the wings off my 48 model. After reinstallation,when I put fuel back in,I had to damn near fill the tanks AND raise the tail way up before there was any fuel in the lines.The reason is that on the ragwing the fuel lines go forward from the tank outlets and down the front door posts,not the rear doorposts like the A & B models. The fuel level had to be brought up to the highest point in the fuel system--where the lines turn inboard & start down the front doorposts.If you're in any kind of nose-high attitude & unport the outlet,you'll have to lower the nose to at least a level flight attitude before you get any gravity feed going on. I don't know if the engine-driven pump is enough to pull the fuel out of the tank and UP to that high point or not,without lowering the nose. A lot of pumps are good at pushing liquid,but not so good at pulling it.
Best solution--don't run so low on fuel that you unport the outlet. Remember,the only time you can have too much gas on board is when you're on fire!
Eric
Best solution--don't run so low on fuel that you unport the outlet. Remember,the only time you can have too much gas on board is when you're on fire!
Eric