Panther Sport Aircraft Forums

Thanks! I think I'm going to go the 3000 route. I haven't gotten the manual yet (kicking myself for not picking it up at airventure) as I wanted to see if i could actually find an engine up here first.

How much of the Corvair engine you need to keep is really a function of what engine you want to build. For all engines, you need at least the case, heads and accessory case with the oil pump. The serious issues with those is corrosion, and damage due to ingesting something while running. Everything else can be bought new.

Pistons/rings and camshaft are replaced for all engine versions.

2775 series use original cylinders that are also available new. Can use original crank, after refurbishment, or use new billet crank.

3000 series use larger bore cylinders that are available through SPA. Can use original crank, after refurbishment, or use new billet crank.

3300 series use larger bore cylinders, and billet stroker crank, new camshaft, new connecting rods.

Check head casting numbers for proper heads, these can be found in Williams conversion manual under the section for heads.

Most everything else like oil pans, top covers, fans, distributors and etc. are removed, and replaced by Williams parts that are available through SPA.

A seized engine isn't necessarily the end of the world, many have been converted successfully, but might cost more depending on your engine choice. It is possible the seizure is corrosion in the cylinders/pistons (not a big deal) or severely corroded crank/connecting rods (less likely).

Cranks are ground, magnafluxed, and nitrided during refurbishment so unless problems are severe or crank is cracked, they can many times be fixed.

Hey David,

I assume this is Corvair? I'd ask the owner if this seizure is a recent occurrence or was that 10 years ago? Has the engine been stored inside or used as a rain collection barrel?

If this is recent, the piston rings are probably just lightly held with corrosion...if this happened ten years ago with no movement since then I'd be wary--there maybe excess corrosion that a cylinder bore/hone will not be able to clean up adequately. I'm not familiar with Corvair conversions but it appears new cylinders are fitted anyway.

To be sure maybe it'd be best to pop a cylinder head off or two and see how bad the cylinders appear or if a friend has a borescope, that may save you the trouble of head removal. If corrosion is light, a solvent soak with liquid wrench or similar can help loosen the pistons for removal.

If the owner is resistant to letting this happen I'd work towards a deep discount or a return policy.

Hope this helps,

Kirbo

My qualifications: >20 years auto restoration and modifications...

Hello all,

I found a local engine, a 1965 model year. My question is its been sitting around and he said he used to be able to turn the crank but now it won't. I'm assuming this isn't an ussue since its getting torn down and rebuilt, correct? Or are there some things i should worry about?

Thanks in advance!

David