stunthanger.com
General control line discussion => Open Forum => Topic started by: Lyle Spiegel on September 10, 2007, 06:15:08 PM
-
Resulting from a minor incident that cost me 2007 MASS CUP at Wrentham my B40 I need to replace the crankcase due to busted off muffler mounting hole- new parts already on order- including gaskets ( shim) for head and backplate.
Any special precautions or unique steps I need to follow inorder to disassemble/ reassemble?
-
Lyle - it's pretty straightforward.
After bringing the piston to TDC, remove the head on the damaged engine. Make a small mark on the piston crown and sleeve. Use this mark when reassembling to insure that the piston/sleeve are at the same position when inserted into the new case.
Remove the sleeve - slight heating with a heat gun may be needed. Disassemble the rod from the crank and then finish disassembly.
Clean all parts, apply oil to the moving parts and reassemble everything into the new case. Double check that the piston/cylinder marks are aligned.
You should not have to force anything - all parts should slide together smoothly.
If the backplate gasket is damaged, you can eliminate it using my sealant method as described in C/L World.
That's it. Tighten everything down, doing opposite screws on the head and you're in business.
Bob Z.
-
Years ago when I lost my Olympic in Iowa, the muffler mount lug on the back side of the engine was broken. Had maybe three threads left on the engine. The front one was okay as the muffler broke its lug. I tried J-B Weld with a new muffler. Needless to say it did not last long. As I was needing less nose weight, I spent the money and got one of the tongue mufflers from Brodak. Cleaned everything with acetone several times. J-B Welded the threaded portion of a screw into the back side of the exhaust lug(or what was left of it). After the J-B Weld set up I bolted every thing together using the tongue muffler. It is a permanent fix as with one of the ball drivers I can get to the mounting bolts. Was in the ARF Oriental until the controls went haywire. May cut into the Oriental today to see what is wrong. Anyway my repair is still holding up after dozens of flights. Have fun, DOC Holliday