1/2 Hour Flying - Beautiful Cool Afternoon

 

Went flying about 4pm this afternoon.  It was cool, 60 degrees, crystal clear, with a 5 mph breeze straight down runway 23. Cruising at 77mph, and 2100 RPM, the CHT was about 345 degrees F.

Heading ESE that's Lake Anna straight ahead and Lake Louisa, where I live, to the right.

When I turned at Lake Louisa I headed SW so I would be south of Gordonsville Airport  to enter the downwind for 23.  Bad plan, I was flying  straight into the setting sun.  Visibility forward was awful.

I also should have flown another 20 minutes so the sun would be better hidden while landing, couldn't see the trees below me turning final.  They weren't close but it was not comfortable.  Then bounced the landing a little, but had fun overall.

Nice Warn Afternoon Flight

 I had to get something from the hangar, for my son, so I went early and had a nice late afternoon flight, for almost 1 hour.  It was about 70 degrees with a gentle breeze down the runway.  I left the traffic pattern for a while and flew around south of the airport.

Coming back I noticed this pipeline running north, east of the airport.  They keep a wide path clear so they're easy to find and follow.  They're also shown on the sectional charts.  Them, high power line clearings and expressways are great navigation aids when traveling in these tree covered states down south.

The airport is between me and Merry Mountain.

Here's a closeup of the white book warehouse north of the airport. If you zoom in and look in front of the strut, and above the spreader bar, you can see Orange County Airport.  It's not the white buildings just above the bar but the tiny ones above then.  OK, I know what I'm looking for.  It's about 6 miles north.

I mentioned the mountains on the west side of the traffic pattern the other day.  Here's what Merry Mountain looks like at traffic pattern altitude on the crosswind for runway 5.

This is it after turning downwind for runway 5.

Looking south was hazy from smoke that came from somewhere way  south of us.

Looking north over the runway, with the sun behind me, you don't even see the haze.

Cool Evening Flight

 Yesterday I went for a nice evening flight. It was a cool 55 deg. I wore my fleece vest under my leather jacket, which kept my shoulders warm.  I should have also worn a sweater, my left arm got very cold, but it was fun anyway.  The wind was 8 knots from a little left of runway 23.  Once in the air it was very smooth.  I didn't leave the traffic pattern, I only had 40 minutes until sunset, so I just went around the airport.

Looking NE from the left downwind for 23.

Looking East, we're well past peak fall colors, very brown.  We mostly have yellow and brown at best.

Looking North, the white building is a book warehouse.  It's an easily spotted reference, except when it snows, which isn't often.

Looking West, the airport is in the lower left corner. Fred's hangar/house/terminal is the white building just by the left edge of the picture.  Merry Mountain is behind the spreader bar.  Scott Mountain is just to the left of the cabane strut, behind Scott is Chicken Mountain.  Gibson Mountain is hiding behind the strut.  Way in the back are the Blue Ridge Mountains. The airport is at 454 feet and the top of Merry Mountain is just over 1,100 feet right next to the downwind for Runway 5.  It looks really close  when you take off on 5 and turn left toward it.  The Downwind for 5 is halfway between it and the runway so it actually is close.  At the point you make your turn from the runway you're still not above it.

Finally Back To Flying

 We had a beautiful evening, more like late afternoon without Daylight Time.  I flew for half an hour and everything worked fine except my camera.  I think the memory card is full.  I have not solved the Cylinder Head Temperature problem, it's still running hotter than it should.  I had fun.  

When I did my BFR I rented a friends C172.  It does not fly like the Fly Baby.  It took a while to work out the traffic pattern positions, but we got there.  The first landing I was almost stopped when we realized the nose tire had gone flat.  We got it on a creeper and carefully dragged it back to the hangar. A piece of safety wire had poked a tiny hole into the tube.

It's supposed to be nice tomorrow so maybe I can take some pictures.

Airplane Ready To Fly

 On March 16th I finally had everything back together and taxied the plane for about 10 minutes.  Everything was fine, except for a slight miss on the left magneto.  Back in the hangar.

On March 18th we had a fly-in to celebrate the reopening of the runway.  The winds at 3000 feet were 26 knots but we had a good turnout anyway

Today I had time and 72 degree weather to work on the small misfire.  I stared by pulling the lower plugs and cleaning them to assure there was not any oil fouling one of them.  I also rechecked the gaps, all good.

When I removed the lead to the lower plug on cylinder 4 the insulator fell off the wire, problem found.  I had cable tied the wire to keep it clear of the exhaust pipe and accidentally pulled it so tight I pulled the lead almost out of the insulator.  I reinstalled the insulator and was more careful how I tied it up.  It's running here before taxiing it for about 10 minutes.  I did 2 mag checks with no misfire.

With it nice and warm I did the compression check.  All cylinders were 75/80psi - 76/80psi., very good.

The annual Condition Inspection is now signed off.  We're ready to go flying to see if I've improved the motor cooling with the grills removed.  Yea!

Runway Closed Again

 

I've been going slow working on the valves because our runway is closed again.  The wizards of smart, who designed the new runway, forgot to put an overun at the north end of the runway.  As it was, as soon as you over ran the end of the runway you started down a 40 foot hill to the creek.

They've hauled and piled soil to create a 100 foot over run.  After that you're heading down to the creek,

It's a huge pile of dirt.  They've carved away every cubic foot of soil from around the runway.  Originally they destroyed our grass taxiway along the west side of the south end of the runway to level the runway.

Now they've removed soil along the west side of the north end.  At one time I could land in the grass south of the VASI panels, not now, it's gone.

When I get my WACO NINE project done I may need to find another airport.  It has no brakes and a tail skid.  It needs grass to fly safely.

Removed Cylinders to Solve Sticky Valve

I've been slowly working on the sticky valve problem.

I removed Cylinder #2, the one with the sticky valve and covered the hole to keep dirt from blowing in around the hangar doors.

I decided to make a new tool for for removing the valve spring keepers.  I tried buying one but didn't like what I found.  Years ago I had modified the handle of my, 7th grade, tack hammer to do the job.  It never worked great but it was my inspiration for this one. I had some 1/4" steel rod, like the hammer handle, so that's what I used.

I cut a piece I thought was long enough, folded it in half and started forming the bends.

The hooked end goes under the rocker arm shaft.

The step down is to push on the center of the spring retainer.

The wide gap is to have room to get the 2 keepers in or out.

With the end hooked under the rocker shaft the tool is pressing on the spring retainer.  To keep the valve from moving as you press down, the valves are resting on the flat top of this wooded block.

The block is made from a piece of 1/2" plywood for the base with a piece of 4x4 screwed to it.  The 4x4 has the corners rounded, to fit in the barrel of the cylinder.  The angles at the top allow the cylinder to set down so the valves are on the top of the wood.  It works real good.  I got the idea from an old training movie.

You press down on the handle to expose the 2 keepers.  I use a good magnet to remove the keepers while pushing on the handle.

I took the new valve and stuck it in the guide from the top to see how far in it went before sticking.  It stopped about 1/4" from the bottom of the guide.  It should have fallen all the way down.  The build up of carbon stopped it.

I didn't want to use a power tool because I didn't want to accidentally make the inside diameter too large and then have to get the guide replaced.  It's a 7/16" diameter hole.

I tried a variety of 1/2" brass and steel brushes.  The brass did nothing.  The steel brushes worked, but very slowly.  I also made a stick of 3/8" dowl to hold Crocus Cloth for final polishing.

The thing that worked best was the small blade on my Swiss Army knife.  Stick the blade in the hole, from the cylinder end, the curve of the blade prevents scratching the wall of the guide.  Use it ase a screaper to scape the carbon as you rotate the cylinder around the blade.  It's still very slow, but better than the wire brush.  I used the brush after scaping with the knife.  It was surprising how much carbon came loose as a fine powder.

I also tried Easy-Off oven cleaner.  It worked well to soften the carbon on the valve stem where you could spray a good coating and let it set over night.  

I used a Q-tip to apply it in the guide but really never got enough to do much.

It might have worked if I could have blocked the end of the guide and filled it with cleaner.

To make sure I removed enough carbon without increasing the hole size, I measured the outside diameter of the valve stem and the inside diameter of the guide.  The book allows 0.0035" to 0.0055" clearance. The stem is easy to measure.  The guide hole rquires a hole gauge, which you adjust to fit the hole, then you measure across the gauge. I had to work from the top of the guide so the longer hole gauge was able to reach the bottom.  The anvils are spring loaded.  When you have it where you want you twist the handle to lock it, then pull it out and measure it, Very tedious.  There was so little wear that the best I could do was get the clearnace to 0.0035".  The valve really moves freely when you have that clearance.

To make sure the new valve sealed well I got some valve lapping compound.  The tube came from Advance Auto and the jar from NAPA.  It turns out they are both the same stuff.  The tube, 80036, was about $5and the jar, 39835, was about $8.  Either is probably a lifetime supply.  It's a water based gray paste with silicon carbide grit, from 120 to 220 grit.

Get a dab on your finger and apply it to the sealing surface of the valve.

Carefully reinstall the valve in the guide so you don't wipe off the grit or get it on anything but the valve seat.

You are going to oscillate the valve against the seat to lap the 2 to the same angle for a tight fit.  They make a stick with a suction cup on the end to do this but it takes a very long one to reach down into the cylinder.  Instead I used the drill chuck from the ShopSmith to grip the end of the valve stem and pull the valve against the seat vs pushing it with a stick.

The lapping process is simple.  With the valve tight to the seat you rotate the valve back and forth about 40 degrees until you feel it moving smoothly.  You really feel the grit at first.  Then move the valve off the seat, rotate 90 dregees and repeat.  Keep doing this in sets of 4 90 degree moves until you barely feel the coarse grit.

Clean everything well to be sure no grit is left to get where it shouldn't be, then pressure test the cylinder to assure you have a seal.  Repeat the process if needed until it seals.  They do make lapping compound as fine as 1,000 grit.  I didn't order any.

I didn't want to lubricate everything, put the piston back in and reinstall the cylinder on the motor just to leak ckeck it.  Instead I made up a plate to seal the bottom of the cylinder.  I used some scrap 1/8" steel, some 3/8" nuts and bolts from Tractor Supply, and some 1/8" cork gasket material glued to the steel plate.

Snug the bolts up and it seals, so you can use the cylinder differential pressure tester to slowly apply pressure.  Yea no leak.

There was no logic by which I can believe this was the only cylinder with carbon built up in the exhaust valve guide.  I couldn't in good conscience put this one back on and ignore the others.  Off with the next cylinder and repeat the process.

When putting cylinder 4 back on I couldn't get the hydraulic valve lifter to compress to get the shaft back through the rocker arm.  I called my friend Caleb Glick, who has since died and will be sorely missed.  He explained that the check ball in the plunger was stuck and that the plunger can be removed with a magnet, then cleaned.  This involved removing the casting which has tabs cast in it to prevent the plunger falling out of the lifter.

Once the casting was off the plungers are easy to remove with a magnet.

The long piece on the left has the check valve in it.  It lets oil flow through the lifter and up the push rod to lubricate the rocker and valve. I blew Brake kleaner in the small tube untill it was cleary open, then I oiled everything and put it all back together.

I found one of the lifters on cylinder 2 was not compressing so I took the cylinder back off and cleaned the check valve on it.  All 8 lifters are now working fine.

Cylinders 2 and 4 are on, and 1 and 3 are off to clean the valve guides.

Cylinder 3 was easy, but I replaced the valve on cylinder 1.  Even though it hadn't stuck it was worse than cylinder 2.  It took more force to pound out the valve.

After the first lapping the valve had some leakage.  I blued the sealing surface on the new and old valves, installed them with no compound, and only oscillated it a few degrees.  There was a small low spot on the seat which needed some more lapping.

 

I also found that the new valve had some chatter in the original grinding.  The 3 arrows point at high spots you gan see in the bluing.  Chatter basically leaves little flat segments with corners between them.  The little high spots, corners, cause leakage until the lapping smooths them down.

I could hear a very slight leak even though the pressure was good.  I put a few drops of soap solution on top of the valve.  You can see the bubbles all the way around the valve at 10 psi.  More lapping.

With the valves working the cylinders are back on and pressure checked just to be sure, all 4 were good.

One side at a time the exhast and baffles went back on and everything was reconnected and safetied.

When I finished today I just need to clean up the mess, do one more inspection, and reinstall the cowl sheet metal, we're getting there.