Here we have a tiny group, the Case. I may later break down the case into smaller more descriptive elements, but for now, it gets the job done. Now, there are a lot of notes that can be applied here, but keep in mind we are just looking at the overview big picture. The one note that I want to point out is that the case has no machine work on a 2700/2850 but the six bores in the case for the cylinders must be machined larger on a 3,000 cc engine. Of course, this is done before it is assembled.
Case Group (1200)
1200- Case -2 halves with studs-
1201- Main case bolts -8-
1202- Pipe plugs for oil galleries -2-
Now, let’s get a look at the four parts so far and think about putting a case together. Using just these numbers as a check list and something of a road map, any builder can put together a plan to assemble their case at Corvair College #25. Actually all the effort to get to that stage goes into the prep work, cleaning and a little shopping. It you lay out all the properly prepared components from groups 1000, 1100 and 1200 in front of me on the bench, and get me an assembly stand and my trusty Snap-on torque wrench “Excalibur“, I can assemble the case in about 45 minutes.
Now I say this in bad conscience because I once took 2 days to do it. There was a tiny ding in one of the bearing surfaces that was putting a small amount of extra drag on the turning crank and bothering me. I took it apart 6 times to find it and make it right. Keep in mind, it’s not a contest, the winning score is being happy with it, and any amount of time it takes between 45 minutes and 48 hours is fine. BTW, everything we are talking about here is in our engine assembly DVD #1 that covers building up a case.
Going back to the first part of this series we talked about crank selection. Lets look at some samples bringing all of this together and see what large variations of choices are available to builders,
Builder ‘Allan Able’ elects to use a Moldex prepped crank, and put off a 5th bearing for now. Lets say his crank has a reasonably good gear on it that doesn’t need replacement. He is going to use the low expense route laid out in the Camshaft section of Part #4
Builder ‘Bob Baker’ elects to use a Weseman prepped crankshaft with a gen 2 bearing hub installed. He is going to keep his used gear from his crank. He is going to get a Clarks standard cam gear, he is going to put in on a re-ground cam himself.
Builder ‘Chas. Charlie’ elects to use a Weseman prepped crankshaft with a gen 2 bearing hub installed. He is going to elect to have a new gear on his crank. He is going to get a Clarks failsafe gear, installed by clarks on a new cam.
Builder ‘Davie Dog’ elects to use a Weseman New billet crankshaft with a gen 2 bearing hub installed. He is going to elect to have a new gear on his crank. He is going to get a Clarks failsafe gear, installed by clarks on a new cam.
Builder ‘Eddie Easy’ elects to send his case and crank to Roy at Roy’s Garage.com. Roy is going to rework his stock crank, install a Roy bearing and use a failsafe clarks gear on a new cam.
In the next few parts we will take a look at how Allan, Bob, Charles,Davie and Eddie are doing on their projects.-ww.
About William Wynne I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 20 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at www.FlyCorvair.com and in more than 50 magazine articles.