Magnum 20 rebuild

Mudrig150

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My brother got a magnum 20 about 2 years ago, and now I'm the owner of it. It has a good amount of issues.
The bore is a mess and full of rust.
The governor gear and oil pump gear are destroyed and damaged respectively.
The crank has a ton of raised edges on cylinder 1.
The rod snapped from being defective.
It's missing the governor arm, the gear, and the carb.
The block is fine, surprisingly, and the crank bearings and the crank for piston 2 are fine.

The halves of the block20190214-164233.jpg20190214-164239.jpg
The chunks of rod left over in the bottom of the crankcase.20190214-164229.jpg
The side that threw the rod. The cylinder jug has a good bit of rust in it.20190216-183735.jpg
The side that had the good piston. The cylinder jug has rust on the bottom edge.20190216-183721.jpg
The remaining piston head. My brother took it out and lost the wrist pin. The rod is there just not pictured.20190216-193147.jpg
 

BlazNT

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The rust is too bad. Your heads are toast. Your cost to rebuild will outway its value.
 

tom3

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I'd start pricing parts before going any farther. Kohler parts are generally twice the cost of Briggs parts and could be hard to find for that particular engine. I agree with the above post, too far gone to be reasonable to rebuild.
 

Mudrig150

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I'd start pricing parts before going any farther. Kohler parts are generally twice the cost of Briggs parts and could be hard to find for that particular engine. I agree with the above post, too far gone to be reasonable to rebuild.

Well I managed to find a guy who has a piston, carb, governor gear, and an oil pressure switch for 65$.
 

BlazNT

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Well I managed to find a guy who has a piston, carb, governor gear, and an oil pressure switch for 65$.

Now all you need is 2 heads, pistons, rods, crank, and valves.
 

tom3

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And a re-bore with oversize pistons and rings to match, which could be a pretty large oversize bore.
 

Ronno6

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I have a 305 Chevy that could be had right reasonable..............
 
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Check out ope engines by the time you rebuild you might get new engine for little over cost of rebuilding with labor and all
 
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