Kitfox 1 Rebuild

35 posts in this topic

Posted (edited)

20180102_134701_25588486038_o.thumb.jpg.

Well today was my first day back to A&P school from the holiday break and I got right to working on my KF1 project. History on it is the previous owner upon landing on his driveway, veered off into the ditch and took out the left main gear. The wingtip hit the ground as well as the prop. The plane sat for about 10 years and then the owner passed away. I bought it from the estate with little to no information or logbooks. Here's the main squawks I have;

  • New left main gear supplied by the family is the wrong size, about 2 inches shorter on the front and aft main tubes. Are there different stock gear from the 1 to 2 and so on?
  • Bent tubing on LH fuselage side20180102_161119_39460880671_o.thumb.jpg.20180102_143511_38580558235_o.thumb.jpg.
  • Collapsed RH Seat truss, will need to be rebuilt20180102_155334_24593999127_o.thumb.jpg.
  • Dial prop flange and complete Rotax 582 overhaul
  • All SB's and SL's need to be complied with. i.e. elevator and rudder pedal gussets and the "Jesus" elevator pushrod bolt
  • Multiple rips and tears in the fabric
  • Needs a new prop
  • Complete condition inspection

Needless to say there's a lot to do but I'm just excited to finally start work on it. Today I removed the interior and seat pans to get a better picture of the bent tubing of the fuselage. I'll be using AC 43.13 as my repair reference but any advice will be more than welcome.

Also the previous owner had a replacement LH main gear built supposedly by Kitfox but it's definitely smaller than the original RH main gear.20180102_160906_27683266409_o.thumb.jpg.

Did the model 2 or 3 have taller gear, is there any difference. If someone has a model 1 would they mind taking some measurements for me to reference?

Anyways any help is appreciated and I'll be updating the thread as I make progress or have questions.

Happy New Year everyone!

Edited by Brodstol

Share this post


Link to post
Share on other sites

Posted

Would be happy to take measurements for you, but I won't be home for a while.  I didn't think Kitfox made different length gear legs in the different models.  The Avid MK IV was a couple of inches taller than their earlier gear, but it doesn't look like you have one of those on the right side.  They had a built in step on them.  Maybe someone homemade one of yours???  Can you get a picture of the difference if any  in the gear legs where the bungees wrap around them?  Not uncommon to see bent seat trusses in these planes.  A weak spot on the Avid Flyers as well.  I've infilled the triangles in the seat truss as much as possible with .040" steel plate to stiffen it up.   JImChuk

Share this post


Link to post
Share on other sites

Posted (edited)

Photo can be deceiving, but I wonder about fore and aft location of your axles - If that taller gear puts the axle farther forward, then it could be an Avid gear or one that someone built, which is good.  I would guess the smaller gear is original Kitfox 1 size.  I have a set in the hanger but cant get there to measure until next weekend.  If I had to make one side, then I would copy the taller wider heavier gear.  EDMO

Edited by EDMO

Share this post


Link to post
Share on other sites

Posted

I have a stock kitfox 1 gear legs Ill be happy to measure them tonight after work.

Share this post


Link to post
Share on other sites

Posted

Thanks guys that'll definitely help solve the mystery. I'll check on the axle placement and I agree the taller, wider gear would be preferred. 

Share this post


Link to post
Share on other sites

Posted (edited)

My gear legs are 22 inches from the upper mounting bolt C/L to the axle C/l. Model 1 S/N 107. Mike

Edited by ppilotmike

Share this post


Link to post
Share on other sites

Posted

My gear legs are 22 inches from the upper mounting bolt C/L to the axle C/l. Model S/N 107. Mike

Perfect! Thanks a lot ppilotmike! I just measured and the original RH landing gear is the same measurement whereas the "new" LH gear is 2" shorter at 20". I'm starting to doubt that the gear came from Kitfox but rather someone else who didn't fabricate appropriately. I'll start posting in the wanted ads for a LH main gear and hope to find one from the many people who've upgraded gear over the years.

Share this post


Link to post
Share on other sites

Posted

The early ones must have been shorter I have some from serial number 11 that measure bout 20.5" They must have made the change somewhere

Share this post


Link to post
Share on other sites

Posted

Huh that's interesting, might explain the mix up. I made more progress of the plane today. I took the 582 off and started the tear down. I dialed and dye penetrated the propeller flange of my "C" gearbox and all looks good. Next I need to get a puller for the stator and the crank flywheel. I'm thinking maybe a steering wheel puller will work. Here's a few pics of the progress.

IMG_6894.thumb.JPG.7d9b03222ef47d39dbaf0IMG_6892.thumb.JPG.4167d68f9508c3ad7fbc020180103_161220_39452390302_o.thumb.jpg.

Share this post


Link to post
Share on other sites

Posted

If you take a piece of maybe 1/4" thick steel plate, and drill 3 holes in it to match the ones on the front flywheel, you should be able to pull that one off pretty easy.  That's what I've done.  Put a nut or socket under the plate, and against the crankshaft end and evenly tighten the bolts.  Unless you are able to check to make sure the crank isn't twisted after the prop strike, I would leave the rest of the engine together and send it to someone who can do that for you.  They could inspect it and reseal it at the same time.  JImChuk

Share this post


Link to post
Share on other sites

Posted

The way that shop looks I bet you could just build a new one that matches. It would be a good Lesson on welding.

Share this post


Link to post
Share on other sites

Posted

If you take a piece of maybe 1/4" thick steel plate, and drill 3 holes in it to match the ones on the front flywheel, you should be able to pull that one off pretty easy.  That's what I've done.  Put a nut or socket under the plate, and against the crankshaft end and evenly tighten the bolts.  Unless you are able to check to make sure the crank isn't twisted after the prop strike, I would leave the rest of the engine together and send it to someone who can do that for you.  They could inspect it and reseal it at the same time.  JImChuk

I did same with a scrap piece of plywood, worked fine.

Share this post


Link to post
Share on other sites

Posted

Just wanted to post an update, the measurements all are good so I'm putting the 582 back together. After assembly this week, I'll be working on the fuel and cooling systems with a carb and fuel pump rebuild, new hoses throughout, and fix/replace a leaky radiatior. 

IMG_20180122_104035.thumb.jpg.0b6900b4dfIMG_20180122_122134.thumb.jpg.8f88b59aaeIMG_20180122_131554.thumb.jpg.aab77fd04c

Share this post


Link to post
Share on other sites

Posted

Looking good!! Mike

Share this post


Link to post
Share on other sites

Posted

Looks great! Love the updates

 

Share this post


Link to post
Share on other sites

Posted

That grey head looks so nice and clean. How many hours are on it?  I'm coming up on 300 hours this year and may follow your lead. I really appreciate the tear down pics.

I noticed the EGT locations look to be possibly too close to the manifold flange. See: http://www.ultralightnews.ca/exhaustsystems/egt_probelocation.htm

It would be a good time to measure them and remedy if you think it’s worthwhile. 

2 people like this

Share this post


Link to post
Share on other sites

Posted (edited)

Av8r_Sed is correct. My plane was having high EGT issues. One thing I found was the probes had been installed on the manifold in the wrong location. There are other articles and explanations. Basically it’s 1 1/2 inches out and center on the short side and 1 5/8 inches out and center on the long side. The measurement was taken from the manifold face without the gaskets.

Edited by NorthIdahoAvidflyer

Share this post


Link to post
Share on other sites

Posted (edited)

That grey head looks so nice and clean. How many hours are on it?  I'm coming up on 300 hours this year and may follow your lead. I really appreciate the tear down pics.

I noticed the EGT locations look to be possibly too close to the manifold flange. See: http://www.ultralightnews.ca/exhaustsystems/egt_probelocation.htm

It would be a good time to measure them and remedy if you think it’s worthwhile. 

Thanks for the heads up, I'll look into this. There are old holes further back on the y-pipe that were welded over so who knows. My 582 had around 50 hours on it and then sat for close to 10 years. It's been a real fun project along with fabricating a whole bunch of specialty tools out of material around my school. I put the gearbox and starter on today. I'm just waiting for my thermostat gasket to finish mounting the ignition and then it'll be ready to get back on the plane20180201_170225_25163034007_o.thumb.jpg.20180201_100921_28255270279_o.thumb.jpg.

Edited by Brodstol
2 people like this

Share this post


Link to post
Share on other sites

Posted (edited)

Well I screwed up this post royally, but as you can see from the pics above that my 582 is now back on the airframe and I'm currently plumbing it up. I'll be mounting the exhaust and a new slightly larger aluminum belly radiator next week, if you have any suggestions or tips let me know. It's coming along and its quickly become a labor of love, I'm having so much fun!

Edited by Brodstol
1 person likes this

Share this post


Link to post
Share on other sites

Posted

Thanks for the updates! Love the pictures as it shows there is more than one way to skin a cat. Mike

Share this post


Link to post
Share on other sites

Posted

I got the oversize radiator installed today. I use the original mounting mounting holes and built a bracket to make it work. I'm pretty happy how it all turned out and it's a little less than a half a pound heavier than the old radiator. Next up the exhaust mount...20180205_131541_39393059194_o.thumb.jpg.20180205_131511_40105178631_o.thumb.jpg.

Share this post


Link to post
Share on other sites

Posted

If you make a little lighter bracket you can loose that pound. No need for 1/4 Aluminum strap there. you could also drill a bunch of 1 inch holes in that area. Just a thought. If you do decide to make a different set up you should lower it about 2 inches for better cooling. I can say this because I seem to make everything two and three times ha. Looks good keep going.

1 person likes this

Share this post


Link to post
Share on other sites

Posted

Just wanted to give a little update, this week I started on fixing the fuselage bent tubing, installed the exhaust and firewall seal, and started to prep the brand new Model 3 gear I bought from Ronin. Last week was the fuel system, battery tray, instrument panel and wiring. I also removed all the Lexan which I'll use as my away from school project at home. I'm still hoping to have it close to if not finished in a month which is also the end of my A&P schooling. My Kitfox will probably be the first logbook I put an entry in as an A&P. Welp back to the grind I go...

20180221_155941.thumb.jpg.76f050ec0652f220180221_160005.thumb.jpg.2bbba0149f7a2d20180220_112454.thumb.jpg.c1477c3055eaeb20180221_160041.thumb.jpg.4c03e2eaed70c420180221_160023.thumb.jpg.4fde1d0565e0a520180221_160249.thumb.jpg.0a5ad02e59b72c

1 person likes this

Share this post


Link to post
Share on other sites

Posted

Hey Brodstol, nice progress.

The one thing I can see I would really look at is your aluminum ? battery strap and your tray mounting. Your battery weight must be around 25Lbs and your hold down device should hold at least 10-12 g's (might be even more) which equates to 250-300Lbs.....you definitely do not want your battery come loose in heavy turbulence or crash...

Here a good mounting method picture: 

 

 

battery installation.jpg

Share this post


Link to post
Share on other sites

Posted

Good point, it was the original design that I modified to be able to fit the new battery. The original design had a bungee cord holding down the battery, lol.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now