Motorstar M-14P Radial Aircraft Engine

Pratt & Whitney Wasp R985

I've always thought radial engines were pretty cool. The crankshaft is simplicity itself: only a single throw. Of course after that it gets pretty complicated, but still, 2,000 horsepower from an engine with only a single throw to the crank.

My Uncle Bill had a couple of andirons in his fireplace made from the master connecting rods from a Pratt & Whitney Wasp radial. He was the one who taught me about using universal joints with socket wrenches.

My brother Andy spent some time working on radial engines in Houston. He wasn't impressed. He wasn't a certified A & P mechanic, so he was probably not making much money, which probably contributed to his attitude. But working on these engines was a major pain. Each cylinder was bolted to the crankcase with a dozen nuts or so, and the only way to get to them was with a box wrench. And for half of them, you couldn't even use a regular box wrench, you had to use a wrench that had been specially bent so you could reach that particular nut.

Motorstar M14P Radial Engine

Still, they are pretty cool. So I'm out stumbling around on the web and I come across the Motorstar web site. They sell Russian radial engines, made in a factory in Romania. Looking through the manuals for this engine and I come across a cross sectional drawing. There's a lot of detail, but the picture is pretty small. Let's see if we can enlarge it. We can and there doesn't seem to be any limit. I try to copy the image and paste it into MS-Paint, but it's too big. The computer can't handle it.

I really like this picture. Is there any other way to extract it from this manual? Well, there is the good old screen-print button. So I do that 20 times, trim the images and paste them together using MS-Paint and we get a pretty decent image. You really need an image viewer that allows you to control the amount of zoom. Windows Picture and Fax Viewer does a decent job. You will have to excuse the gray and white lines on the image. I was trying to get by with as few screen shots as possible, and I pushed the limits a little too far. Click on the image to get to the big one.

Motorstar M14P Radial Engine Cross Section

Update January 2017 replaced missing pictures.