Sexton R975-C1 a mess

[LRDG]

Originally Posted by Bob Phillips

Malcolm- for whatever little bits its worth- those splayed out cylinder bottoms may be a pain to disassemble but maybe they will have saved the thin cast aluminium that makes up the crankcase. Later engines (eg the -46 helicopter) has much heavier castings in it. It also rated at 600 hp with much more blower and carb action. I cannot tell you about the fins, I always thought they were machined in but I don't know..Bob

Good point, Bob. You are right, they did save a lot of damage to the crankcase.

It's pretty well apart now and disassembly has stopped as there is some angst about repair costs.

There is some interesting damage to the crankcase in the raised web that supports the lifter bores. It's shown below. It lines up exactly with the inboard end of the starter drive shaft (last photo, 6 o'clock position). It's like the nut on the starter end of the shaft had come loose and allowed the shaft and small gear to move inboard and wear into the web. And it doesn't look like old damage because there is wear debris coated on the web that's not shown on the photo. It's like the nut came loose and when it was spotted (or heard), somebody just retightened the nut to pull everything back into place and hoped for the best. The weird thing is there absolutely no sign of damage or wear to the end of the shaft or the gear. It's a bit of a mystery to me.

Thanks again for all the suggestions on parts but things are on hold for a while.

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