# JMR SPecial project. My design.

Discussion in 'Member Project Logs' started by Pops, Aug 21, 2013.

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1. Mar 22, 2019

### Pops

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Looking back to some of my first drawings. The date is 8/15/10. But had several other Bearhawk projects alone with it.
It will be finished when its finished.

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2. Apr 9, 2019

### Pops

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Installed an old exhaust system that I had, don't know what it came off of. Maybe someone will know. Just put it on to start the engine for the first time. Need to route the plug wires and install the fuel line to the carb. Thinking of making a complete new exhaust system. Will be good to hear the engine run again after I did a MOH on it. View attachment 84133 View attachment 84133

3. Apr 9, 2019

### Pops

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4. Apr 11, 2019

### Pops

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I went to the local Aeroquip hose distributor and got the -6 fuel line from the fuel strainer to the carb made. I had some fire sleeve for the fuel line. On the small Cont engine a -2 hose and fitting is used from the engine to a oil pressure sensor. They didn't stock any -2 hoses and fitting. I would hate to pay for a -2 hose from a Cessna dealer for the hose as used on a Cessna 150 with the Cont 0-200 engine. I would have the big one from the sticker shock. So I went shopping and found a -3 hose and fitting with 1/8 pipe threads. That will work and I can live with the price. I'll be putting an orifice in the fitting at the engine case end.
Aircraft Spruce doesn't stock any -2 hoses and fittings for oil lines.

https://www.verociousmotorsports.co...-Assembly-1-8-NPT-Straight-x-Straight?whence=

Last edited: Apr 12, 2019
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5. Apr 24, 2019

### Pops

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About ready for the first start up. Need to prime the oil system before start up. Pulled the JMR out of the hanger to sweep the hanger out so took a couple of pictures. Mags timed and wire leads routed. Still don't have the instrument panel labeled. You can see the bent exhaust stack on the right side. Might use the down tubes from this exhaust system for the new system when I make it.

6. May 23, 2019

### Pops

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Drew up plans for a new exhaust system. Was thinking of modifying the old exhaust system in the last picture but it just not going to work and have required distance from the lower fiberglass cowl and the fuel line from the fuel bowl to the carb. Thinking of a more of a straight down system somewhat like the exhaust system on a C-150 but without mufflers. It will keep the heat off anything important and simple and light weight ( something I can understand )
But in the meantime I'll use this old system to do some ground running. Thinking of making it from mild steel until I get it just what I want and then making a jig and welding a system using stainless steel.
I keep putting off starting the paper work, I'm just going to have to bite the bullet and get started. I do know the "N" number that I need to get reserved for it.

Found a grounding problem with the left position light and strobe. I thought I made a mistake one time, but I didn't
Starting to work on labeling the instrument panel. Saving room for a 8" tablet for the flight instruments.

Pops

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7. Jun 27, 2019

### Pops

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I got sticker shock when pricing a set of Cessna 150/172 vented fuel caps. Wag-Aero had a vented cap for $46 and an un-vented version of the same cap for$9.50. I ordered 2 un-vented caps and drilled and welded a vent tube. Epoxyed primed and painted red. Saved $73 for welding 2 little tubes. This is homebuilding isn't it ? #### Attached Files: • ###### DSCF0008.JPG File size: 87.8 KB Views: 19 • ###### DSCF0011.JPG File size: 28.3 KB Views: 19 FritzW, wsimpso1, Joe Fisher and 7 others like this. 8. Jul 12, 2019 ### Pops ### Pops #### Well-Known Member Joined: Jan 1, 2013 Messages: 7,404 Likes Received: 6,366 Location: USA. Engine ready to start for the first time. Pulled it out of the hanger and tied it down. Put one gallon of fuel in each wing tank and checked for leaks (None) and marked the sight gauge for the one gallon. Turn the fuel on and the quick drain started dripping on the temporary exhaust system and the primer leaked when you shove it in to prime the engine. So no go on the engine start up. Need new quick drain (all the others are new) and new O-rings for the primer. #### Attached Files: • ###### DSCF0001.JPG File size: 109.6 KB Views: 52 Last edited: Jul 12, 2019 FritzW, Joe Fisher, jmt1991 and 3 others like this. 9. Jul 16, 2019 ### Pops ### Pops #### Well-Known Member Joined: Jan 1, 2013 Messages: 7,404 Likes Received: 6,366 Location: USA. In replacing the Curtis drain valves, Aircraft Spruce sells a socket to fit the drain valve for$52. Just take a deep well 7/16" socket and a cutoff wheel and make a couple of slots 1/2" long. Works good. 1/4" or 3/8" drive well be OK.

Forgot to add, have the drain valve locked in the open position for marking the socket for the slot and when installed in the socket.

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10. Jul 17, 2019

### Pops

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Finished making the electric elevator trim pushrod. All finished except for the rod end jam nut. The leading edge tube for the elevator is 3/4" in dia and the servo in inside of the elevator. Elevator is balance with the servo installed. Very light weight but very powerful. Made the trim tab a little oversize and if to effective, I'll trim down to suit. I had the same setup on the SSSC but with the next smaller servo. Works very good.

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11. Jul 20, 2019

### Pops

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I put a slip joint in the baffling between the cylinders. If you don't put some type of slip joint between the cylinders in the baffling, it will crack.

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12. Jul 22, 2019

### Pops

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13. Jul 27, 2019

### Pops

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I put some fuel in the wing tanks for the first start on the engine. Tanks pressure tested before installing. Check for leaks in all the fuel line fittings. Looked good. Next morning there was a strong smell of fuel in the cockpit. On the right side the fuel line comes down the rear of the door post and has a union behind the seat. Small leak at the union were it would evaporate as fast as it was leaking, so no drips just the strong smell and a small damp area. Tried to tighten more, but it was tight. So I took it apart and checked the flairs, they looked good. I made a new line from the tank down to the union fitting and tried again. Same leak. Took it apart again and inspected the fitting. The part of the union fitting where the slope of the flair contacts had a defect , you could see the mark the aluminum flair made on the blue fitting except for about 1/16" space on the fitting. Tried another union from my collection of new fitting and now no leak. Going to throw the fitting in the trash to make sure it doesn't get used .

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14. Aug 4, 2019

### Pops

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Did an empty W&B and numbers wasn't the same as before. Checking the scales out, slightly different reading each time I weigh something. Been using these scales for many, many years, but no more, they are going in the trash.
Bought a new set of scales. When I was building the engine mount I came up with a length of 9.5" for the mount to put the empty CG where I wanted it. Then after bolting the engine and mount to the airplane and checking the CG, I needed to move the engine forward 3/4". I thought I had made a mistake and turned 3/4" long aluminum spacers between the engine and engine mount and order longer bolts. So with the new correct reading scales I don't need the spacers for the W&b to come out correctly. But, one problem, I made the fiberglass cowl with the spacers installed, so now have to cut 3/4" off the back of the fiberglass cowl. Some day you get the bear and some day the bear gets you.
Are we having fun yet? Yep.
New N# is N87CV
Thought I made a mistake onetime, but I didn't.

Last edited: Aug 4, 2019
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15. Aug 14, 2019

### Pops

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In making the Stainless Steel exhaust system I finally found the .035 thickness tubing for the system . Cost was 2 times over the .050 that is easy to find. Would have about \$300 in material for the system.
I was talking to my neighbor and he went to his huge parts collection and gave my an almost new exhaust system from a C-85 Champ. Vary little work to make it fit just the way I want. Weight for each side is 2 lbs and 3.5 oz. I never did like the carb heat muff on the Champ so I'm going to build a new carb heat muff on the right side exhaust.

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16. Aug 15, 2019

### Pops

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Need to get the exhaust system a little closer to the engine because of the cowl. Mounted and cut slots on the inside and moved the bottom over 2". I'll be cutting the bottom crooked bottom end off and welding it back on straight down. Like the exhaust stacks on a C-150 or Cont powered C-172. I'll tack weld and remove than finish the welding. Then while off the engine I need to make the carb heat muff for the right exhaust stack. BTW-- That airbox is a Stainless Steel airbox that my old friend Dallas welded up for me. Best made.

Last edited: Aug 16, 2019
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17. Sep 4, 2019

### Pops

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I have 3 things to finish. Making the carb heat box on the right exhaust system and cutting the holes in the lower cowl for the exhaust stacks. The third is somehow sealing the slot in the firewall for the steering pushrods to the nose gear. I made a alum plate and a leather seal with a slot for the pushrod to go up and down, but you can see in the pictures there is still a slot for air to enter the cockpit. So going to try making a silicon rubber boot to go on top of what I have how. If that don't work, I'll get someone to sew a leather boot. I think the leather boot would be better, but I'll see what I can do with a rubber boot.
Make a modeling clay mold for the rubber boots. Many years ago, I made rubber female mold to make model airplane fiberglass cowl this way.
Don't know how much the rubber will stretch as the pushrods goes up in its travel . In normal usage the travel will not be that much. Thinking of putting the rubber seal on the inside of the firewall where there is less travel. Trial and error.
Now need to buy some high temp silicon .

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18. Sep 15, 2019

### Pops

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Finished cutting and rewelding the Champ exhaust for the angles needed. Now to add the carb heat box on the right side exhaust. The outlet pipes are long and will cut it to length after cutting the holes in the lower cowl and mounting the lower cowl.

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19. Sep 15, 2019

### Pops

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Finished the Silicon rubber boot for the nose gear steering boots, ( post #177. Came out better than I thought. Will be mounted behind the firewall and the end will be close to the rod ends on the rudder steering horns where there is very little up and down travel as the nose gear goes up and down in its travel. That will make the pushrod opening air tight.

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20. Oct 30, 2019

### Pops

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Finally got the carb heat muff made. Need to run the scat tubing to the airbox and finish running the engine crankcase breather tube down the rear of the engine.
Now to locate and cut the holes for the exhaust pipes in the lower cowl.

Added--- Being so short, I wraped the pipe inside the heat muff with a long spring to help with the heat transfer.

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Last edited: Nov 2, 2019
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