Swift Fuel System Page 3...

MORE ON THE FUEL VENT ISSUE... (050200)
Subj: Vent Lines
From: Larry Simms <larrys@abs.net>
Jim, Was reading the discussion on Swift fuel vent lines. I had a GC1A and converted it to a GC1B by installing a C-145 engine. I remember seeing several different configurations of the vents and listening to the stores of erratic fuel gages. Mine always indicated correctly and I don't fix things that are not broke. My Swift had two vent exits, on the top and bottom of the airplane. The top one was just aft of the "shelf" behind the cockpit. On my airplane the top hook faced aft. At one time that hook got filled with mud by some industrious wasp. I didn't notice it during my preflight and took off with a full tank of fuel. The airport operator saw me leave trailing a cloud of fuel from the bottom vent and tried to contact me but I had turned off my radio and didn't get his message. After about 20 minutes of flying I returned to the airport and was met by the FBO. There was about 3 gal. of fuel remaining in the tank when I landed, however, the fuel gage had indicated full all of the time that I was in the air. We concluded that the vent line that originates at the top of the fuel gage standpipe will see a negative pressure (vacuum) when the top vent is plugged. Once the siphon started the fuel gage float remained at the top of the standpipe regardless of the amount of fuel remaining in the tank and indicated full. I fitted all of the vent line exits with fine mesh screens. This airplane also had a vent adjacent to the left fuel tank on the top of the wing. This happened in 1959 at the New Smyrna Beach airport, Florida, and was reported to the FAA. Thought I would send this to you in case it is applicable to any of the Swift fuel vent systems now out there. I don't recall the serial number of my Swift but the wing number was N90305. Sincerely, Larry Simms

Larry,
N90305 is s/n 319. I used to own s/n 335 which had the same vent system. The fuel gauge was not too bad, but when going cross country, with the tanks stuffed "full" it was necessary to fly right wing high until a couple of gallons burned off to avoid siphoning out the right vent. I never did get around to correcting that! -- Jim

IN SOME CASES THE "RIGHT WAY" IS NOT THE BEST WAY??? (050200)
Subj: Fuel vent route
From: Larry Owen <T081763@sphn.com>
One of the side effects of having the vent line done "the right way" is often found out here in West Texas. If you top off your tanks on a warm day, you may find it bubbling out over your aft section as it heats up and expands. Paint and lettering will not stand up to that for long and it will really mess up a good bare metal polish job. My wife Deb always complained that she could smell gas until I stopped filling the tanks to the brim. Bob may have a "hot weather" Swift setup. Just my 1 ½ cents. -- Larry Owen N78287

FUEL VENT COMMENTS... (050300)
From: Terry Straker <TASGuitar@aol.com>
Subject: Re: May #2 GTS Internet Update and vent lines
Since Jim asked for comments, here is my 2 cents worth on vents. My Swift- N31W SN 408-used to have the vent out the top of the right wing and another atop the fuselage behind the baggage bulkhead facing forward. Worked fine for fuel delivery, but poor for gauge accuracy. Nagle did a canopy on it about 11 years ago, and left the right wing vent. The fuselage vent was run from the top of the fuselage down the passenger side to the belly and out the bottom. Still delivered fuel fine, and it was always very easy to tell when it was full as fuel impressively spouted out the right wing vent during taxi after a fill up.

Now I have the vents running outboard from the tanks and around the centersection spar ends (no holes drilled thru the spar web!) down the front of the spar to the "tee" that Joe sells that joins the standpipe, etc. It then runs down the pilot sidewall, up over the top, down the passenger sidewall and out the belly as before. Dry wings and a fuel gauge that is VERY accurate. Never any siphoning or problems of any sort. I still log every gallon of fuel and the tack time in a notebook at each fillup and check against my known fuel burn, but it has always been right on the money as to fuel quantity. The setup on my Swift could not work better unless the fuel was free. -- Terry Straker

HE READ THE BLUE BOOK. NOW WANTS MONTY'S ADVICE... (050400)
Subject: Left Fuel Tank Leak
From: Bob Runge <ejectr@javanet.com>
Jim, It appears I have a leak in my left tank. I got a pretty steady drip off the trailing edge inboard of the flap. Is the procedure in the book a good one to follow and pretty thorough? Is there anything not mentioned there that I should be aware of?

Bob,
As I recall, the procedure in the blue book is pretty good. I will read it (again) later today and write you if I can add anything. -- Jim

IS THAT AN ORIGINAL SWIFT PART??? (070400)
Subj: Gascolator
From: Porter Houston <phouston@erols.com>
Monty, Do you know of a source for the Gascolator gaskets? -- Porter

Porter,
Not exactly, but the screen is the same physical size as some Cessna airplanes, so maybe the gasket is the same too. Do you have an aircraft parts seller locally? I see Aircraft Spruce has 3/32" x 2 1/8" replacement gaskets for 30 cents each. -- Jim

"CALL SWIFT PARTS FIRST": SWIFT PARTS HAS THE GASKETS...  (070500)
Subj: Re: Gascolator
From: Porter Houston <phouston@erols.com>
Monty,
FYI. A local IA and myself determined the Gascolator gasket is the same as used on a Beech Travelair model 95. part #33-199-6. It's 2 1/4" dia. The gasket supplied by Swift is this Gasket. -- Porter

FUEL VENT MODIFICATION QUESTION... (070500)
Subj: Fuel Vent Mod, Info Ltr #16
From: Stephen James Martin <stevmart@pottsville.infi.net>
A friend of mine who is restoring a "46" wanted to know if you can fill in some blank spots in the Info Ltr #16 concerning rerouting the fuel vent line. 1) What are the dimensions of the doubler where the vent passes through the spar? 2) What is the gauge (thickness) and composition of the doubler? 3) Any opinions on performing this modification? Thanks for your time, I'll be sure to pass on any information you may be able to provide. -- Steve N2622K

Steve,
I presume you mean SB #25, which is the latest bulletin on the fuel vent system. The doubler is .040 2024 Alclad, about 2" x 2". Most guys, instead of drilling a hole in the spar web just run a loop of 3/8" aluminum tubing from the top of the tank, around the end of the centersection between the wing attach fittings and inboard down the front of the spar. -- Jim

DRIP, DRIP, DRIP... (110300)
Subj: Fuel cut-off
From: Marvin Homsley <marvin@accesstoledo.com>
Jim, There is a minor fuel system mod I would like to do and would appreciate your advice. At my last annual I needed to pull the main fuel filter to check it out. I found out that simply selecting "OFF" with the fuel selector does not cut off fuel to the fuel filter. I had to drain the entire contents of the fuel tanks before I could work on that filter. I know there is a way to re-route the fuel lines so that the fuel selector really does cut off the fuel to that filter. I will really save me a lot of trouble in future annuals to do this. I just need some expert advice on how to route the lines. I am prepared with a brand new tubing bender and fittings. Thanks. Marvin Homsley N80740

Marvin,
Well, you understand what you want to do. Perhaps you want to make a sketch of the desired routing before you start. You want the shut off before the gasculator so the screen can be removed without losing the entire contents of the fuel tanks. The routing would be - tank - shut off - gasculator - carburetor. -- Jim

SOUNDS LIKE A GOOD IDEA BUT...(110500)
From: Marvin Homsley <marvin@accesstoledo.com>
Jim, I have been under my Swift for a few hours today. Mostly spent in deep thought instead of real wrench twisting work. I was going to re-route my fuel lines so the fuel selector would turn off the fuel prior to the gascolator. I may have a much easier way of doing this. The whole reason I wanted this modification was so I could remove the gascolator at annual without having to drain the wing tanks first. Instead of re-routing all the lines, why not just put a manual shut-off valve in the line that goes from the sump to the gascolator. That valve would only be used once a year and left on all the rest of the time. I am installing a new fuel selector valve at the same time. The old valve was not as hard to remove as I had anticipated. I work slow but careful. Marvin Homsley N80740 >>

Marvin,
That would work, but would be a built in booby trap. The FAR's (CAR's in 1946) direct the routing to be tank - on/off valve - gasculator - engine. By rerouting to that configuration you are correcting something that Globe evidently slipped by the CAA. A non-standard extra valve in there leaves the possibility of inadvertent shut off and flow restriction. You could call it a "maintenance valve" and safety it securely. Be sure it flows as freely as a 3/8" fuel line. If you do something like that without paperwork you may confuse subsequent owners of the airplane and cause an incident years in the future. After all, we are just caretakers of these birds, now in their first 54 years! -- Jim

AT LEAST HE TRIED SWIFT PARTS FIRST! (120100)
Subj: Old style fuel drain
From: Paul Nyenhuis <pan@cftinet.com>
I am putting Warren White's Swift back together. I am looking for the old Kohler drain valve that was in the sump and gasolater. I checked with Swift Parts and Univair no dice. What I am trying to retain is being able to drain the gasolator from the firewall. I' m familiar the other types available but need the blade on the valve which was turned activate the drain to work in the existing configuration. I will replace the "o" ring if I can find a serviceable old type. These were also used in the Stinson tanks and gasolator drain. Do you have any ideas? Thanks, Paul Nyenhuis

Paul, I would think a Curtis drain valve or any 1/8" NPT valve would work. I seem to remember replacing an "O" ring on the drain valve on my own airplane at the last annual. Yeah, if you want to have the ability to use the original type of operation from the firewall you are pretty much confined to using the original valve, so you need to find a replacement "O" ring. -- Jim

LEAKING FUEL CAP...(010101)
From: Steve Roth <Swift97B@aol.com>
My fuel cap is in two pieces, riveted together -- one is the main piece that screws into the fuel tank and other piece is a "disc" which has the fuel info printed on it. I got the new disc at Athens this past year -- figured it would look nice having new printing on it. I have been plagued by a fuel leak around the cap. Initially, I thought it was the cap gasket. But not so. So, I believe it is leaking around the rivet which holds the chain and disc to the fuel cap. Anybody have any suggestions on what to do? I have thought of installing a new rivet using fuel tank sealer when I install it. Would epoxy work? What kind is fuel proof? Is there any other easily-obtainable sealer I could use? Fuel tank slosh sealer comes in big containers. I only need a thimble full. Thanks, Steve Roth

Steve: I believe if you shoot a new rivet in there, it will not leak. A rivet swells so tightly in the hole it should eliminate that problem. A little epoxy on the rivet should not be necessary but epoxy will not react with gasoline. If the hole for the rivet is not clean use the next size rivet. -- Jim

MARV IS GONNA DO HIS VENTS...(010101)
Subj: vent system
From: Marvin Homsley <marvin@accesstoledo.com>
Jim, I have a chance to get my plane in a nice heated hangar for a few days. There is a project that I am considering during that time. I have the drawing of the latest fuel vent system from the association. I have read about it in your maintenance tips book. But I have a couple of questions about the procedure. Of course I need to pull the wings, I can probably handle that. My main concern is having space to work on the vent lines once the wings are off. Is there enough space to get to the existing vent lines without pulling the fuel tanks. I do not want to drill any holes in the spar but some of your info says you can route the lines so this is not necessary. I really like one place in the maintenance tips where the procedure is summed up very briefly. It says, to just run a line from each wing tank to the center of the plane, join them together, then run it up and out the roof. I like that kind of directions. Right now I still have the old style vent coming up out of my right wing. It spills gas and is taking the paint off the wing. Any tips are greatly appreciated. Marvin Homsley N80740

Marvin,
The service bulletin is #25. Read the service bulletin. To briefly recap - pull the wings. Install an AN822-6D elbow at the top of each tank. (or you can cap off the extra 3/8" AN flare leg of the "T" fitting.) Changing the fitting with the tank installed in the centersection may not be easy! Run a 3/8" line outboard around the attach fittings and then down to the cockpit just forward of the spar. "T" it near the LH sidewall and run a 3/8" line up behind the cockpit, aiming the vent facing forward. This sums it up pretty quickly. I just did this job on s/n 199 so I know it can be done! -- Jim

WHY DID THIS ENGINE FAIL??? (020501)
From: "Bradberry, John" <JBradberry@grocerysupply.com>
Subject: GC-1B N80951
Remember the fatal crash of Swift GC1-B N80951 in Texas on December 18, 1999? If this has been in the newsletter, I've missed it and therefore disregard. I understand the "unofficial" (un-published) cause of that crash was due to the automotive fuel pump which was an approved installation. Seems some check valve components that float around in there are just the right size and shape to get lodged (and did) and cause a blockage when the pump is installed with an AN fitting. No problem when the pump is installed with an automotive fitting . . . just an AN fitting. This was the second fatal crash due to this problem. Further, I'm told the FAA doesn't quite know what to do about it. ????? I suppose if someone wants more information, they might try contacting the NTSB facility in Dallas. Just thought I'd pass this along. -- John

John,
I don't know. The Facet (Piper 481-666 or later replacement) fuel pumps have 2 ea. 1/8" pipe tapped holes for AN fittings. The Swift association had a special version with 1/4" pipe holes. Neither of these should present any problem. N80951 had a Franklin engine, I don't know if that installation requires a different electric fuel pump. Even new airplanes from the factory have a placard on their Facet fuel pumps, "For Automotive Use Only". I think that is strictly for the lawyers. I subscribe to an Aviation Maintenance magazine. One month, a mechanic wrote in, "In doing an annual inspection, I found this Facet fuel pump placarded "For Automotive use only". I thought, You dumb _____ they're all like that. The next month there were several letters and an editorial comment saying, "They're all like that". If a fuel pump has anything other than a pipe thread for the fuel line fittings I certainly would not use it. -- Jim

We also asked Steve Wilson <SteveWlson@aol.com> NTSB retired, his opinion on this matter...
Hi Guys... N80951 was converted by Don Short of Stillwater, OK, sometime in the late 80's or early 90's. He and his son flew it off a dirt strip near Don's home. I own the original cowling from that airplane. I may use it or part of it on N3876K. The airplane was purchased just prior to the accident (maybe a few weeks or so) I did not know the guy who purchased the airplane from Don; do not know his experience level in a Swift, etc. I have not talked to Don about the airplane since the accident. As to the allegations of fuel pump problems, that certainly could be true. The airplane had a 220 Franklin conversion and was normally aspirated. Personally I do not know of any fuel pump problems peculiar to the Franklin engines. I have never heard of the automotive Vs AN hardware configuration. Someone more familiar with them will have to address that issue. I know that the 125/145 hp Swifts go from 3/8" into the fuel pump to 1/4" from pump to carb and many have automotive fittings in the 1/4" section, but that is the way they came from the factory. So what's new? Anyway, I do know that "some" Lycoming fuel pumps did/do have a poppet valve problem, but to be truthful, I never got too interested because I usually have little to do with them and figured if it were serious enough to make it to an AD, I would deal with it when it came my way. Of interest, I did call the FTW NTSB and asked if they needed any help on the accident at the time, but they seemed to have it under control. I will give them another call on Monday and see what I can uncover. If I find anything interesting, I will get back to you. I know that the accident report has not been made public yet. So, just the fact that it is that old, might indicate some complications. We'll see... SW

(EDITOR SAYS... The flight instructor in me wants to say that fuel pump failures do NOT cause fatal airplane crashes. Pilots do...)

A LITTLE BACKGROUND BY JIM ON FUEL PUMPS...(020501)
A little background on the electric fuel pumps used on the 125/145/150 hp Swifts. To my knowledge, they were originally made by Bendix and used first on the 1963 Piper Cherokees. (the Apache used a similar pump a few years earlier) The Piper part number was 181-666. The inlet and outlet were tapped for a 1/8" pipe thread. The fitting used was an AN816 nipple with a 1/8 pipe thread and an AN6 flare or an AN822 elbow with a 1/8 pipe x AN6 flare. Any observer would note that the fuel passage through a 1/8" pipe fitting is pretty small. On the Piper, there were parallel fuel lines for the electric pump and the engine driven fuel pump to the carburetor. When the pump was adapted to the Swift the two pumps were in series, so the total fuel flow had to go thru the electric pump. Not the best idea, but it has never seemed to be a problem. Note the FAA requires 3/8" fuel lines and AN6 hardware on 125 hp installations. The 1/8 pipe fittings, also used on the engine driven fuel pump, present a significant restriction. Again, this has NOT been a problem. As I mentioned previously, there were Facet pumps available with 1/4" pipe threads for the inlet and outlet at one time. The fuel pressure required for the O-300 is 6 psi. maximum and .4 psi minimum. Many guys get nervous when the fuel pressure gets down to one pound, but this is double the minimum. -- Jim

STEVE WILSON HAS MORE ON THE FUEL PUMP QUESTION...(020501)
From: Steve Wilson <stevewlson@aol.com>
As I promised, I called the NTSB office in Ft Worth today. As you might figure, the actual cause of the accident will come down as the pilot not maintaining control of the airplane due to his distraction from an engine failure. The reason for the engine failure was indeed fuel starvation due to a faulty mechanical fuel pump. The failure mode was as John described it.... Something loose in the pump that blocked fuel flow. The STC for the electric pump in all the Swifts I am familiar with depends on the integrity of the mechanical pump to work. So.... if you have a blockage or catastrophic failure of the mechanical pump, the electric pump, and for that matter the wobble pump, ain't gonna hack it. You are in the landing mode! Monty or Charlie might address the high HP conversions. I don't know about them. I do remember someone at one time (Bill Menefee I think) used check valves to make the system redundant. I personally think the check valves may have a higher incidence of failure than the modes we are talking about in the mechanical pumps... Oh well, just thought I would bring you up do date. Apparently the factual report will be out from the NTSB soon... Cheers, Steve W

GAS DRAIN... (040401)
From:Darrel S. Kester <dskester@worldnet.att.net>
Dear Jim,
Another question if I may. Currently, the gas drain cock protrudes from the belly of the plane. I am told this is a fire hazard - a true fear of mine in aviation. This drain extends down from a glass bulb collector which sets in front of a square metal sump. It seems like the glass collector is not the lowest point in the system but rather the sump. The Fuel System and Fuel Vent System diagram (figure 29) is not too clear. And I have had other try to explain the best way to plumb the drain. Could you describe the best way to accomplish eliminating this fire hazard problem. Thank You , Darrel S. Kester dskester@worldnet.att.net

Darrel
The Swift originally had an aluminum gasculator in the belly, not glass. It did not protrude, or have a drain from it that did, but there was a drain line from the sump that did. Usually a rubber hose is used for that drain line, which should be a minimal fire hazard. To pull the screen in the gasculator, many owners have found to their dismay, that they have to completely drain the tanks because the gasculator is located before the fuel shutoff. Evidently, Globe Aircraft in 1946 snuck one by the CAA. Many Swifts have had this "corrected" and the plumbing has been revised to allow shutting off the fuel and pulling the fuel screen. With a tubing bender and the right AN fittings the job can be done so cleanly that it looks like "factory". -- Jim

MORE GAS DRAIN... (040401)
From:Darrel S. Kester <dskester@worldnet.att.net>
Looking at the sump (and I have to remember because I don't have the plane close at hand), there was a plug exiting from the rear. I was thinking of placing an AN elbow from this rear fitting and then putting a "push up" drain just short of the skin. I guess I could use a rubber tubing as well to a drain installed on the skin. But the former system might be a little simpler to ferry home.

Darrel
The push up drain would create a fire hazard. If you think about it, a belly landing would cause the valve to open and drain gasoline. Not a good idea. I would suggest the original type drain valve and a rubber hose. -- Jim

LEAKY FUEL GAGE, ETC... (060401)
Subj: Leaking Fuel Gauge
From: darladoc@sport.rr.com (Doc Moore)
Hello Monty:
I am a new Swift owner having bought N3817K from Connie Mack, Jim Ball's widow. I am reading all I can but have more questions than I can find answers for. Would like to ask for your help on some items. The fuel gauge does not work and stays on empty. When I fill the tanks fuel will eventually seep around the gauge bolts causing a strong gas smell in the cockpit. Once fuel is burned down some the seeping goes away as does the smell. The gauge worked once after filling and flying but then has stuck on empty again. This has all occurred in 20 hours of flying. Can I pull the gauge and change a gasket? Make one from scratch or buy one somewhere?? Why would the gauge stick on empty? Bad float? Have not pulled it out to see how its made. Any suggestions on how to troubleshoot and repair? Is new gauge available? Plane has an O360A1A with Altuair cowl. Oil cooler is mounted in front on left side. Cooler is an 8 row, Harrison I think. Engine runs very hot... right at red line here in Louisiana now that its hot. I don't know what the calibration of the gauge is so am going to heat water to boiling tomorrow and check the calibration. My question is.... whats the best place for the oil cooler and also, is there a formula for inlet air opening vs exhaust air opening? The opening in the bottom of the cowl is not very large so am wondering how to troubleshoot all this in terms of moving air through the cowling and also the oil cooler. The baffling is all in good shape. Got many more questions but won't deluge you with them all at once. Thank you for your help. Doc Moore, Shreveport, LA

Doc
If the gas guage doesn't work it is usually related to the vent system. You need SB #25 complied. Consult the service bulletin book and the blue "Maintenance and Operation Information for the Swift" book. The latest version of SB #25 might be available from the Swift Association. Simply put, from the tanks, a 3/8" vent line runs down thru the wheel wells to the cockpit where it goes back to the aft fuselage and out the upper skin with the "hook" facing forward. There must also be a vent line above and below the gas guage, see the SB diagram. The guage itself can easily be removed. The cork float can be recoated with shellac. If there is leakage at the gasket a little "Fuelube" will take care of that. A lifetime supply of Fuelube can be obtained from Aircraft Spruce or other suppliers for a few bucks. I don't think there are new guages available or do you need one. For cooling, perhaps the best suggestion I have is to simply use a bigger cowl flap or open it at more of an angle. Usually, the left side mounting of the oil cooler works well, a 4" duct may be necessary to get enough air thru it, as well as an exit duct. -- Jim

CORROSION IN THE FUEL TANKS? (100101)
From: Patricia Barnes-Webb
Hi Monty,
I've been getting flecks of what appears to be corrosion showing up in my fuel tester the last few times that I've drained fuel for my pre - flight checks. I'm not too sure where I go to on it now, apart from starting the (reputedly) long and painfull process of pulling the fuel tank to see what it is and where its coming from. Do you have any ideas, both on the possible source of the problem,and what the quickest and easiest way might be of dealing with it? All the best, Anton Barnes-Webb

Anton
If it's aluminum corrosion it usually has the appearance of white flecks floating in the fuel, or flecks on the screens. The little screen at the carburetor should be pulled first and checked and/or cleaned, then the fuel pump screen and the electric fuel pump screen. (if installed) The main screen at the gasculator in the belly can be a little problematic. As plumbed originally all the fuel must be drained before it can be removed. If you haven't done this for a while perhaps now is the time to do it. The most likely place for corrosion to exist is in the sump in the belly. (it's called a "trap" in the parts book) If water has been allowed to sit in the main tanks, there may be corrosion at the aft inboard corners. The "trap" can be removed and repaired by welding or they have some new ones at Swift Parts. If the corrosion is from a ferrous part (brown rust) you should be able to determine what and where it came from by checking the same screens. In either case, a complete draining of the fuel system is a good idea. If the corrosion is not severe, after complete draining of the fuel system a gallon of "Alodine" or other aluminum treating acid could possibly be poured in the fuel tank and flushed thoroughly. 3M makes a fuel tank sloshing compound called EC-776 which will stop leaks and plug any corrosion pits that may exist. I hesitate to use it, because it may make future weld repairs difficult and it may react to some fuel additives. I think 3M markets their products in South Africa. Whatever you do, be careful, and make sure your fuel is not contaminated before further flight. -- Jim

GETTING YOUR FUEL GAGE TO DISPLAY CORRECT QUANTITY... (1105201)
Subject: Fuel gage reading
From: George McClellan <WWIIPILOT@aol.com>
The fuel gage will read full on the ground and in the air just after the plane has been filled. One hour of flying and the gage reads 1/4. When I land with !/4 showing it will move back up to 3/4 on the ground. I have a Lyc 0-320 and burn 6.5 gph. How do I get the gage to read right in the air? I have had this problem for years but never have flown long legs so was not bothered by it. Thanks for your help George McClellan N655S

George
This is a common problem and I am surprised you have not heard of it before. The problem is in the fuel vent system and is corrected by compliance with SB # 25. Your airplane is a converted GC-1A, s/n 374. I formerly owned s/n 335 and had the same problem. To change the vent system to the later type is a fairly big job and requires the wings to be removed and vent lines to be installed running thru the wheel wells and a single external vent on top of the fuselage with the opening facing forward. I looked in the blue "Maintenance and Operation Information for the Swift" book and I didn't see anything on this. If you want the gas gauge to read correctly you will have to get SB # 25 done. Vaughn and Scott at SwiftWorks are familiar with SN # 25. -- Jim

GEORGE HAS ONE MORE QUESTION... (1105201)
Subj: Re: Fuel gage reading
From: George McClellan <WWIIPILOT@aol.com>
Thanks for the reply. I have a vent that is located on top of the fuselage about two feet aft of the hatch. is this standard or has the vent been modified. It does face forward. How would I be able to tell if the mod you are talking about has been done by looking at it visually? George
George,
It should be about two inches aft of the skin lap aft of the hatch. ( about sta. 90) To see if SB # 25 has been done, look in the wheelweels, there should be a 3/8" fuel vent line running parallel to the hydraulic lines from behind the gearbox into the fuselage. If you have the vent line above the tank running inboard to the fuselage, you have the earlier vent system. You can see this by removing the aft belly panel. -- Jim

...AND BRUCE HAS ONE MORE QUESTION... (1105201)
From: Bruce Ray <swiftfly@hotmail.com>
Jim
One last question on N80644. I have fueling ports on both wings. Both of the fuel caps seem to be seeping just enough fuel to mess up my clean wing. What is recommended for the seal on the caps. Thank you again, Bruce Ray

Bruce,
This is not a common problem. Some fuel caps have actually had a small hole drilled in them to equalize the venting. The only way to stop those from leaking is to shoot a rivet in the hole. Normally, the gasket supplied by Swift Parts prevents leakage. If your fuel caps are drilled make sure the main vent is open. -- Jim

FILL’ER UP...(010502)
Subj: Weird Fuel Thing
From: John Cross <crosses@houston.rr.com>
Hi Jim:
I went to fuel up the other day and the plane took 14 gallons, not the 22 gallons I expected. I suspected that there might be a blockage in the vent for the right tank, and spent a few hours checking out the vent system (I have a bubble canopy). Anyway the vent system seemed to function properly. I was wondering if there is some kind of valve inside the tank that might be a problem. I read through the fuel system stuff on the web site, but maybe I missed something. I will go through the blue maintenance book today. The next suspicion is that there could be a blockage in the cross-feed. I certainly have had the opportunity to hone my trouble-shooting skills with the Swift! Now that I have had it for a year, however, I think it is the best airplane a fellow could have. John Cross, N2398B

John
No, there is no valve inside the tank. It sounds like a vent problem. Since it took about half the fuel it should have, the crossover pipe might somehow be blocked but I can't visualize that happening. I wonder if the vent from the right side tank is blocked. Your s/n is 3698 so you have the late vent system with the 3/8 vent line running from the right tank, through the wheel well and T'ed up with the vent which used to be behind the cockpit, which now is looped to go down thru the belly. Be sure you get this figured out. Maybe you can disconnect a vent line in the cockpit area and determine if the right tank is venting. -- Jim

...upon further review...

We are wondering if you may have been trying to fuel too fast. Did you let it sit for a few minutes and come back and try to get more fuel in?

LANDING WITH THE AUX TANK SELECTED...(020202)
Subj: Dumb Fuel Question
From: John Cross <crosses@houston.rr.com>
Jim:
Is there any reason not to land with the 9 gal aux tank selected? I have gone through the stuff at my disposal, and haven't found an answer.

John
I don't recall ever reading anything against landing on the aux tank, but don't think it is a very good idea. If it is full, that means you have been flying with 9 gallons of aft fuel on board for the whole flight and presuming the mains are burned off to a low level, you may have an out-of-limit CG. If the aux has been selected for anything approaching an hour, it may run dry at any time. Not a good idea on short final! Proper procedure would be, takeoff and climb on the mains, enroute cruise at altitude on the aux until dry, then return to the mains for the remainder of the flight and landing. Using the aux with a constant power setting in cruise also gives a good chance to check fuel consumption. You should check your particular aux tank several times over several flights to determine how much useable fuel you get out of it. Don't just rely on the book figure of 9 gallons. Fuel injected engine operators must remember to burn off enough fuel in the mains to allow space for the return fuel. If they have the big outer wing aux tanks they may have to monitor the fuel guage. If the mains become overfilled and the aux is selected, return fuel may be pumped overboard thru the vent system. -- Jim

AUX FUEL TANK OPTIONS...(030402)
Subj: Fuel Tanks
From: John Cross <crosses@houston.rr.com>
Jim:
I have the 9 gallon (actually 7 useable) tank. That plus the mains gives me about 3 1/2 hours with the O-360. What would you recommend to increase fuel capacity? The only reason I am interested is that another hour of fuel would make the Swift much better for the occasional IFR flight. Really, with required fuel reserve, you are limited to about a 250 nm leg. John Cross N2398B

John
Personally, I only have a 2 hour bladder, so I don't see the need for great quantities of fuel. There are a fair amount of Swifts around with the outer wing aux tanks, with a total capacity of over 50 gallons. There are also a few with a field approved wet wing centersection which also results in over a 50 gallon capacity. There are the Alterair belly tanks which give an additional 9 gallons, so if you used them in conjunction with what you now have, would give you 44 gallons. Year ago, I seem to recall Skip Staub had all the above plus fuel carrying tip tanks for a total of 60 some gallons. There are field approved modified aux tanks like yours which hold up to 16 gallons. Also, there are some field approved outer wing tanks which add 13 gallons. I feel, that to make a "tanker" out of a Swift kind of detracts from the whole character of the airplane. There are Piper and Cessna models out there with factory options for carrying large fuel quantities. I don't fly IFR, but I can recall several trips to Oshkosh from here (about 250 nm) where it was marginal VFR or VFR on top, I recall flying 100 miles on top and got nervous and turned back to good VFR. I do have the belly tanks now, (extra 9 gal.) -- Jim

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