4/1/2008
Today I got the wheels and tires out of storage, and took them to work with me. My friend, and A&P, Ray Ortega gave me a lesson on packing wheel bearings and tube & tire installation. Starting with the bearings, he did one wheel (two bearings), and I did the other side. Here are the wheels after being disassembled.
These do come with grease already in the bearings, but I have no idea how long they've been on the shelf before they came to me. They probably didn't need to be re-packed, but I wanted fresh grease in them at this point.
They come with Mobile aero 100 grease in them, but at work we use Aeroshell 22 for wheel bearings.
Ray showed me how to take the bearings apart. First, the snap ring comes out, then there is a washer-type ring, then a felt ring (to keep water out), then another washer-type ring, then the bearing.
The bearing then goes in to a device that squeezes grease in to the bearing. You can see the red grease coming out, and the tan stuff replacing it.
After that, the grease gets spread around the bearing, and the race on the wheel, then it all gets reassembled.
On to the tires...First, talc powder gets spread on the inside of the tire and the outside of the tube.
The tube is then installed in the tire. The talc powder allows the tube to slide around in the tire easily. Without powder, it will not budge. The orange dot on the tire is from the factory, and serves as a marker to line up the valve stem. The valve is removed from the stem at this point to inflate the tube to fill the space, but not hold air.
The valve side of the wheel goes in first. It's a tight fit for the valve stem through the grommet in the wheel, but Ray said this is normal for a new wheel.
The first one was a struggle, then second went in easier.
It's important to check that the wheel half is lined up properly with the valve stem before the other half is installed.
The other half is then installed to just hand tight on the nuts and bolts.
Then the tube is blown up one more time before the valve goes back in, and the air released. This is done to expand the tire to the rim, and make sure the tube is not pinched between the wheel halves. Then the valve is reinstalled.
Once that is tightened down, the nuts are torque'd, and air is put in the tire. I didn't have the specs with me, so we just put 29psi in for now. I'll check later to see if it's high or low. That psi number came from the psi charts for the nosewheel on a 152 that uses the 5.00-5 tire.
Here we have two completed, ready to install wheels and tires!
I will have the airplane on it's gear this weekend!
1.25 hours