Slow turning over

My old (1960-70) Sears Suburban, 12hp has been very slow to turn over ever since I first got it about 5 years ago. It usually starts but you'd think it hardly turned over once or twice very slowly. I replaced the regular 12V tractor battery with a car battery but it still turns over slow. It has the old belt drive starter and I also swapped it with another machine - still slow cranking. Any ideas as to how to get this sucker to spin over better ?
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Use heavier battery cables. Make sure you have a good ground connection.
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If that is the one that the starter is also the generator there is not much you can do. If you mess with it to much you will burn the starter part out. If it is starting I would leave it alone. You could take it to a automotive electrical shop and have the armiture turned and new brushes.
From Mel & Donnie in Bluebird Valley
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Srgnt Billko Wrote:

Yep, The compression release is worn out on the camshaft, To fix i replace the cam. I've owned 5 of these Suburbans and sold all but on hydro drive machine to pull trailers, cars and boats around with. On of these days I will pull the moter off and rebuild it and put the ne cam in, But for now it does start so I let it ride.
Good Luc
-- restrorob
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Bingo ! That makes sense. I've seen something about "compression release" somewhere on the engine but didn't know how it works. The only experience I had with cr was on a snowmobile 2 cycle engine 30 years ago and that had a lever you pushed. I saw no such gizmo on the Sears so I assumed it was some kinda magic inside. I have a few of them too - so maybe I'll look into getting an estimate. I do like those old suckers, and like you, I do use it as a tractor - pulling a disc harrow, moldboard plow, wagons of firewood, etc.
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