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corvair motor was junk!


Well-known member
Looking to buy my first boat and i fould one locally here in iowa. It is a fiberglass hull, corvair motor, direct drive wood prop, and a complete boat. Supposedly the motor only needs a tune up.I am going to look at it wednesday evening He wants 500 bucks. I realize this thing isnt a powerplant but could it make a good starter boat?

I know absolutely nothing about corvair engines except that they are air cooled and rear mounted. Any advice or comments appreciated.
Heres a tip.

If the boat runs grab it if all else is ok.

THEN, check out a gear or belt reduction drive and make that Corvair come alive in the water. Depending on the model some were around 210 HP but none of them could really perform at the direct drive RPM required. Now that redrives are easy to get, add that and you will have a decent little boat that performs well.

Just thinking out loud here, Id like to hear Dave's Thunder on this one too.

Scotty :wink:
if you get the corvair engine, a suggestion:
pull the fan shroud off and locate the oil cooler, they had a tendency to seep oil. and
mixed with dust and dirt would clog the air flow raising oil temp., many a corvair engine
died early because of excessive oil temp.
I had one of those engines on my Pietenpol, homebuilt aircraft. It was suppose to be 100 hp but with a prop on it was very similar in performance to my A-65 Continental. The prop turned backwards, so, you have to have one made. On the aircraft most folks take the cooling fan off the top but I would leave it on for airboat operation. For $500 you can't go wrong. If the motor quits running you can always throw a cheap VW engine on it.
any idea if the carb off of a 2 barrel chevy would bolt onto one of these? Im really hoping this deal works out so i can get rid of my itch to step into an airboat this spring. Then i can start to build another boat from scratch, not be in a huge hurry, and build it right....gear and all! :wink:
Lord I cant remember who, but back in the day, someone was making tubular intakes that adapted a 2 or 4 barrel Q-jet to them, Im sure there was a Holly and AFB adapter or version as well.

Scotty :idea:
will i be able to get by with just a regular flatbottom hull? Des moines you probably ride in the same type of waters that i will with the exception of the OCCASIONAL run into the main chanel. An extra wide extra deep boat would be nice but i just dont know enough about this to know how it will handle with a sbc.
thank you
You can run a single barrel carb if you want to. You can hook up just about any two barrel. On mine I had an intake manifold made to use an updraft Zenith single barrel but you could shorten the intake and make a downdraft unit. I would run the prop as a direct drive and start with a 66 x 32 wood prop. A 3 blade warp drive would be good too.

The Corvair engine weighs less than 300 pounds so you could get by with a 10 x 6 foot hull but I would still get at least 24 inch sides. When you get hit by a jet ski wave or a tow boat wave in the main channel you'll understand. You could stay close to shore but then you had better know where those wing dams are.
Clarks Corvair parts in Shelbourne falls Mass. has a large catolog with new and used parts for corvairs they have about anyhing u can imagine and manufacture alot of thier own parts. We still run corvairs in this area I might be able to be of some help please feel free to pm me if I can be of assistance.
I picked the boat up tonight and let me tell you it is not very handsome. but what can you expect for 500 bucks right? Spun the prop by hand and motor has compression, 10x6 fiberglass hull with no leaks but rough, nice and long tilt trailer, DD wood prop.

sorry des moines i should have specified... Im going to get this boat on the water by spring so i can start on my smallblock boat and not be in a hurry to finish it. I want to build it right, gear drive...etc. so i am asking if an extra wide and deep flatbottom will suit my needs for the boat i will build???????

thanks for the info PLEASE keep it coming!
Read the link that I sent you, the carburation/intake part might be the life and death of your engine.

The average RPM back then was 1700-2200 for daily driving. Running any automotive engine past that for extended periods without the proper modifications will get you towed in or walking out.
i read it last night. A friend of mine runs this engine on a dune buggy and says it is very dependable. But as you pointed out, the normal rpm curve/range does not apply to airboating.
well, the boat is completely apart! Im going to rebuild the carbs,clean up and do some minor changes on the rigging, And i think im gonna grind the bottom of the hull down to original fiberglass and do some reglassing. I was mistaken it is actually a 11x6 hull. One of the owners had plexiglass bolted into the bottom for running the river on the ice. The last owner took all that off and layed resin across the whole bottom. I am assuming this will not work?????????????(Insight Please) I figured that i got it cheap enough that i can afford to try and restore the hull?????

The prop was looking very weathered so i lightly sanded it to a smooth surface and there are no visible cracks or rotting. Actually the original color came back out of it. Any ideas on what to seal it with?????Im having a riot working o this thing!