It's been a while since I posted to this thread. Here are a few pictures of a .90 class engine I recently picked up for $58.
Here are a few (poor) pictures of my ASP engine. I would describe the engine as “good enough”.
A few notes:
-- Nothing is finished particularly well but everything seems to be functional. Even if it is not pretty, it appears well manufactured.
-- Notice the face of the exhaust port is not machined. Nor are the undersides of the mounting lugs. The neck of the carburetor is still a bead blast finish and un-machined. IF these surfaces aren’t flat there could be trouble. I have no reason to believe they aren’t but it would be nice if they were milled to remove doubt.
-- The head appears to be machined from a piece of billet and anodized black. It is big, six bolt, one piece, and takes a standard 1/4 x 32 plug. It appears to be very functional but not pretty.
-- There are small nicks on various parts where they seem to have been dropped in a bin with other pieces after production.
-- It does come with a woodruff key and prop drive washer but the shaft is short enough that getting a prop, washer and nut on the front might be difficult. I don’t know how it would do as an airplane engine. Bench testing might be tough.
-- The carburetor is well made but extremely simple. It is a ‘70s vintage two needle carb. There is, of course, the standard high-speed and low speed needle. Mid-range is dependent on a cam action that moves the carb barrel in/out as it is rotated. That makes the taper of the main needle and the milling of the barrel slot that moves the barrel in/out critical. Done correctly this can work well. Done poorly and there is NO adjustment (short of grinding the HS need to a new profile). There is a surprisingly pretty and thoughtful throttle arm extension.
-- My biggest fear was that there were some non-standard dimensions on the engine. I was afraid the mounting dimensions for the case or muffler were incompatible with typical kits and mufflers. I didn’t get all the measuring tools out but it appears the engine is completely compatible with the OS I pulled from storage for comparison. It should just drop right in.
The real test is how it runs. Outwardly it looks good but if the internals aren’t right, it’s just a paper weight. A lot of times when you buy a helicopter engine, you’re really buying a helicopter carburetor with an engine attached. This could turn out to be a great engine that won’t function without replacing the carb…. Or it could be fine just the way it is.
For me, the value of this engine is to suggest to others what it might really cost to produce and sell a .91 class engine.
Did I to mention this thing was $58 dollars?
"Well, Nothing bad can happen now."