It never ceases to amaze me how the smallest project can snowball into an entire day's work. I started Thursday to complete the installation of the oil sump. First you have to install the oil suction tube. I had cleaned up the one that was in the engine however on close inspection , I did not like the look of the solder that holds the screen. That sent me searching for my plastic tub full of these. On comparison with the others it became clear that the screen had been poorly repaired because it was a 1/4 inch shorter than all the others.
This also reduces the inlet area because two additional rows of holes are blocked.
I doubt this would make any difference but since I had better ones I replaced it. So I clean up 3 possible candidates and select the best for installation. This tube is installed in the bottom of the accessory case and is sealed with a copper crush washer.
You will notice that the only way to torque this is with a crows foot wrench installed on the torque wrench. This sends me searching for the Part 43 that has the formula to correct the torque wrench reading for the additional moment arm. With the safety wire installed I attempt to fit the sump and it won't fit down flush on the flange?
First I thought that is why the tube was shorter, but that was not the problem. It turns out that when tightened to the specified torque one of the hex points was blocking the sump from fitting flush. After trying 3 different crush washers I ended up filing off the offending point a little. I tried grinding out the sump but got nervous about the wall thickness. I guess the 4 quart cub model sump is not made to fit the c-90 engine that normally has the larger 6 quart sump. Here is how I had to file it off.
With the safety wire installed it was ready for the sump.
You can really see the difference between the aluminum crankcase and the magnesium rear case. While a little rough in spots it still has a lot of useful life remaining. Finally the sump is installed.
See that filler neck clamp bolt below the right engine mount? Notice there is not enough clearance to install the nut with the sump tightened down. So I have to loosen everything , pull it back, install the nut and then tighten the sump. Between the head scratching , hunting for stuff, and figuring the best path forward this consumed almost a whole day!
Friday I completed the cylinders for installation( except for the valve springs) They are clean and everything is measured and ready for assembly. Of course since they are new, everything was right on spec.
Everything has this black manganese phosphate coating, supposed to help it break in properly.
They are ready to install on Tuesday when the springs arrive.
Today (Saturday) I spent the morning installing anti chafe tape on the upper cowling. Then went out to the airport after lunch and check fitted the cowl. I then completed the throttle installation with the new rod end bearing I got on Friday. I also completed the carb heat and the primer installation. The last item here is the magneto wires because I forgot to take out the terminals. The only possible holdups might be the cold tappet clearance (will have to order pushrods) and the ignition harness. With some luck and perseverance I might be flying next weekend!
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