ChrisBolkan

I do not think there is any difference between an under cambered magnum rib and an under cambered  MKIV rib.

Have you talked to your local FSDO? I think if you approach them and say you have a couple of wrecked deregistered amateur built planes (say a couple, just make sure you are being honest and have some actual parts from another source so you would pass a lie detector :-) that you want to MODIFY and put together as a built from parts plane. I KNOW this is acceptable practice. What you need to determine is level and type of MODS FAA thinks is OK for the 51% rule
Find out what they want to see, what they expect the DAR to ask for and so forth. if you work with the FAA first, document who you talked to there, your questions and their answers, you are prepared to talk to the DAR when the time comes and have someone to refer the DAR to. I think I would take an approach something like that.
This approach beats trying to re-register or finding a nameplate because you will be the builder and get the repairman cert. This is appropriate because it sounds like you are indeed making some major modifications that would definitely qualify you as "building" the assemblies even though you are just modifying them (fuse, wings, tailfeathers etc.)
Again, just thinking out loud.
Chris
 

Here is a real world example. A friend bought a rans s-6 that had never been registered. it was legacy from pre sport pilot ultralight trainer days. He brought it home and took it completely apart into individual pieces basically (except for the wing rip/spar assemblies. he ended up ordering a bunch of parts from Rans (I do not know if that is important) because the steel fuse was rusted beyond use. Anyway he (we, I was with him) went and talked to the local FSDO and explained the situation. We found that at least in our experience these guys share a love of aviation and want plane to be in the air. It did not feel to us like they were there to come up with reasons to shut us down. They said "sounds like you are building it from parts you got here and there". He built it as parts and has the repairman certificate, even though it is technically still a rans S-6. I think there are more cases of situations like this than most realize. Most of the time with a lot of thought and actually communicating to work toward a solution things can work out.  
If you are truly COMPLETELY rebuilding a plane, it's hard to prove where the parts came from AND most technical authority figures will realize the fact that it is a COMPLETE rebuild so essentially you are building from scratch and will give you a break.
if on the other hand you are only proposing repairs to a wrecked plane that is repairable, the case will be much harder to make.

How did the DAR know that you did not get wings from one place, a bent up fuselage from another, and an engine and mount from somewhere else? Plus you said you are performing mods. Seems like you need to present that what you have is disparate parts from multiple sources and not just a wrecked plane you are re-building. 
It can be done. A bit different angle but similar situation are the myriad of "experimental" Cubs and similar piper rag and tube experimental planes. Builders get parts from various wrecked planes, wings from a cub, fuse from a PA-12, tail feathers from something else, do a few custom mods and what was once a bunch of pieces of once certified planes is an amateur built experimental.
So you should be able to present a case for build from parts. The great thing about that is you are the builder
Another less desirable but possible option is to buy (or be given) the nameplate of a wrecked but not de-registered airplane and put yours back together under the nameplate. The downside to this is you do not own the repairman certificate.
These are just some thoughts.
Chris
 

Here are my thoughts taken from a previous thread with an interesting twist. The thread was started by Lorax on Oct 1st, 2021 if you want to look it up.
Me:

Probably going to get hammered for saying this, but if you have a chance to get an unused grey head for a good deal grab it! Assuming it has been kept inside and not left out in the weather, I would replace the carb boots and any external rubber and put it on the plane and run it. Break it in properly on the ground (just in case). Normally I have done the break in procedure in the air over the airstrip I fly out of (just in case) because it is much easier to perform in the air than on the ground. But you don't know anything about the engine.

Make absolutely sure since it is a grey head with rubber seals that you either buy pre-mix dexcool or mix up your own with DISTILLED water and those rubber seals will never give you a problem. If the engine runs and works great as-is, fly it and gain confidence until you trust it and then fly the shit out of it. When you decide it is time for an overhaul send it to lockwood or another reputable shop and have them put a ceramic seal in place of the rubber if you want.

You might want to get a couple of the carb "short kits" or whatever they are called (the rebuild kits that only contain gaskets) and if the carbs give you any problem during startup and break in, rebuild the carbs.

Make sure you plumb the oil reservoir in properly, fill it with oil properly using the bleed screw, and watch for any drop in oil as you break in and run the engine for the first several hours. If all is good you should be money!

Like I said I may get hammered for saying this but I see no reason to do a time only rebuild of one of these engines if it is "new" and been kept in decent indoor conditions since purchased.


 
Jim Chuck:

Couple of years ago, I picked up a Kitfox 3 project that had never been finished.  It had a never run 582 gray head with it.  I have a shop nearby me where I have taken probably at least a dozen two stroke engines to over the years, they have a good mechanic.  He pulled the engine apart, and didn't find anything wrong except for this.  When the engines are assembled in the factory, they use an assembly grease to protect against corrosion and initial lubrication on start up.  That grease was close to 30 years old, and was all dried out.  He washed it all out and the bearings were fine but he figured there would have been problems if I had just run the engine without the teardown.  Of course new seals were installed on the reassembly.  That engine had a C gearbox, and I took that off myself.  The front bearing didn't run smooth, and I figured it was maybe corroded.  I sent the gearbox off to Steve Beaty at Airscrew performance to change out the front bearing and it was the same as the engine.  No problem with the bearing, but the assembly grease was all dry and caused the bearing to appear to be bad.  That is my experience with a never run rotax that was 30 years old.  Make what you will of it. :-)


 
Me:

I will acquiesce to Jim's experience with a new old "in the box) engine. My experience has always been with engines that have at least been previously run....but some not run for WELL over 10 years. I have always used the approach I described above and had great results. But those engines had been run previously, so any grease applied during assembly would have been diluted and gone. My experience is first hand including performing all disassembly, inspection, overhaul and re assembly activities myself (with the exception boring cylinders).

I have seen first had with my own eyes what the 582 looks like inside at all phases of time in use many times. If it had been previously run I would still recommend what I suggested above, but in light of discovering dried grease in an un-run engine, it is probably best to disassemble it first and clean up the dried grease.

Thanks for not letting me steer him in the wrong direction Jim.In the situation above the engine was “brand new” and I think Jim’s concerns were valid.


 
So....... If this engine is already sitting on and aircraft and has been flown, I still stand by what I posted above.  

Anyone even remotely interested in a Catalina will want to take a serious look at this plane.
I know Jo personally. He's the real deal. This plane is the real deal. I've watched the progress. Jo is an incredibly capable builder who pays absolute attention to detail. Everything must be "right" or it doesn't happen on his projects.
Chris

I never had a problem drawing too much from the lighting coils. I ran LED landing lights, LED strobes, a full sized radio, mode c transponder and GPS and never had issues with charging the battery during flight. I even ran seat heaters at cruise in the winter.
It's important to understand that at idle and lower RPM the lighting coil puts out much less current, so while idling, taxiing and so forth all of the accessories are really running off the battery, so only run the seat heaters at cruise :-)

That's good!

That's interesting. I read that years ago and was interested in experimenting with it but never did. As I see it, there should be no difference at high angles of attack and slower flight like on landing. VGs on top would affect that.
It seems that any beneficial difference would be at the fastest possible cruise speed when the air is (maybe) stalled out under the leading edge of the wing due to the under camber. Is it really stalled out? I don't know. But if it were stalling it would be at the highest cruise shallowest angle of attack, and closer to the tips of the wings where washout is greatest, right?
So IF the air is stalling under the outer portion of the wing at your maximum cruise speed when angle of attack is least, then the VG's should make that air stick better to the wing, reduce drag and increase your top speed potentially, right?
I don't know. Just thinking out loud. It might be that IF this is true and it WILL work, that the engines we are running don't have enough power to actually get the angle of attack flat enough to get the air to stall out under the portion of wing with the shallowest angle of attack, which would actually be the steepest angle of attack under the wing, right?
Maybe a dive could test the theory if engine power alone won't? But how would you actually measure and improvement in cruise speed or wing efficiency at high speed? 
I'm way out of my league here, but it is sure fun to think about!
Chris

More like a tiny Superb Cub. It has conventional ailerons and flaps. Plus rudder trim! Who puts that on an ultralight with pull start? It is a ton of fun, but after flying my massive 700 lb empty weight Fat Avid, this feels like I am trying to fly a leaf!

Hi Bryce! I had not heard of Bear Perkins so I sure can't help, but just want to say Hi!
I picked up a little ridge runner II ultralight that I am currently tinkering with while my Fat Avid is down for repairs to the starter / and probably sprag clutch assembly. 
The Ridge runner is a hoot! What a little ripper of a plane! It's fun doing the first flights and working the bugs out.

Thanks for all the input so far!
I went to the plane and ran a couple of tests. My engine serial number is 4425382. It looks like the engines with the fretting problem fall in the 5645xxx serial number range.
The check for fretting is to measure the torque it takes to turn the engine over with one plug removed from all cylinders. If it takes over 150Nm (110ft-lbs) there is a problem. It takes less that 110 ft-lb to turn my engine over with the plugs installed a long as I move slowly through the compression strokes. 110 ft-lb seems like a lot to me but it's what's in the book and my engine takes a lot less that that to turn over so I think I'm good on the possible fretting issue.
Then I jumped the battery with a real solid 12V and tried to start it and it did not crank much if any faster, and was still kicking back (wanting to suddenly stop) so it looks like the battery is OK. 
The Battery is an odyssey PC-680, not PC-612. Senior moment. Anyway it is the same battery model I used to start the 0-320 in my magnum. If it is good it has plenty of power.
So then I thought what if I just ground the ignitions and crank it? If the problem is the ignition firing before TDC grounding the ignitions will eliminate the kick back. So I cranked it with no ignition spark and it STILL cranked slow and kicked back.
I am convinced it has to be the starter motor. I am going to remove it and see what the heck is going on. It will take a while to get this done, but I will report back with what I find.
Chris
 

Just reading about the fretting issue now. Haven't got to how to check yet, so need to finish the threads. However it seems like if the engine were tighter one would notice when pulling the prop through by hand. Mine seems fine to me, but I'll keep reading. I sure don't want fretting to be the problem with my engine!

Happening all the time. Hot or cold. A little better when hot, but not any different that the normal difference of hot/cold starting.
Battery is a few years old. Will know if that is the problem when I check cranking voltage and check for voltage drop. Haven't done that very obvious thing yet. 
No idea if crank case id fretting or oil is leaking into the starter. Will find that out when I take the starter off.
I was just wondering if anyone had seen problems with the starter motor itself. Doesn't look like it.
I'll do the voltage drop tests, which will also verify battery condition and if all checks out I will pull the starter.
Thanks guys!

You will be very disappointed if you put a subaru on the front of your model A. Even though it is a lot of power, the plane will not perform well at all. It will require a lot of lead in the tail to bring it into weight and balance. By the time you get it into a nice flying rearward CG with all the weight you have to put in the tail, you will be at gross weight with one person and some fuel. Its tempting because of low cost and it is a four stroke, but the A is just not designed for that much weight up front.
Weight is everything.
My personal choice for the A would be the HKS if they were still being made. Unfortunately they are not and I do not know if there is any support even if you could find one.
In lieu of that the 582 would be a real ripper on the A if you keep it light, and the engine and mount will be much easier to find. 
Just my thoughts...
Chris

Be glad to help call two5two,923 5145, Ask for Snaps....
I finally managed to get on line here! Thank you, I will call when I return home! This little Ridgerunner weighs 400 lb empty. It's kind of a 1 1/2 place. Haven't flown it yet but will when I return. I think its going to be a ton of fun. Looks a lot like your last photo of the little sky raider.
Chris

That's what I did. Just hooked a bit of line to V and let it vent overboard. I figure that's there just in case the diaphragm breaks. I had to put a tiny orifice in the P line because the needle vibrated like crazy until I did. I am sure there are much better ways to do it, but I took a round lead fishing weight, crushed it, and shoved it in the line upstream of the gage. It did pretty well at limiting the pulses getting to the gage so it now reads steady.

Wow! That is impressive. A nice combination of plane and pilot!

That's too cool!
 

that's going to be a fun plane!
 

IMHO, having done the bottom entry panels, and having helped others do the same thing on Avids, they won't leak. Period. Unless one does a crappy job.
I am not familiar with Kitfox wing and tank construction. On Avid's it is definitely easier to go in from the bottom of the wing due to the construction of the wing. The fabric is bonded directly to the fiberglass of the tank. In Kitfoxes, construction may be different. I don't know anything about how tanks are installed in Kitfoxes. 
Bottom line from my perspective is you want to go into the tank where fabric is glued directly to the tank whether it's the top or bottom of the wing, because that is the most direct way to get into the tank AND it allows covers (or how ever you seal the tank back up) direct access to the raw fiberglass of the tank. 
There is no intrinsic advantage to going into the bottom of the tank. 

I think there is wood on the top of the wing over the fuel tank. I could be wrong. Also I took the wings off which made it easy to access the bottom. It would be much easier to access from the top if you are leaving the wings on the plane.
FWIW, I have always been concerned about coating tanks to make them ethanol proof. There is always someplace that doesn't get coated, or an entry or exit point that fuel can access the raw fiberglass or the coating just doesn't stick. I use only ethanol free fuel myself. If it were me, I'd strip all that old shit out of there and assuming they are not leaking, put them into service without any coating and use ethanol free.
If it turns out you have a leak, it's easy to pop the covers off because you used sealed all aluminum rivets that drill out SUPER easy and removable polysulfide sealer for tank covers on the plates that cover the holes so you can go back in if you ever have to and seal the leak with polysulfide tank sealer.