'72 Johnson 25hp compression readings

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mtnwkr

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I have the opportunity to pick up a '72/73 25hp long shaft, tiller, Johnson for $cheap. It's been sitting and barely runs, but did run well before sitting, or so I'm told. The compression readings are 115 on the top and 110 on the bottom. Does this sound OK? It would need the carb rebuilt along with tune-up, water pump, probably seals, lower lube change, etc. I don't want to put the money into it if it's not going to be great when I'm done, I'd rather spend more if it's necessary. Thanks!
 
Pressure readings over 100 psi and within 10% of each other is good.
 
I agree over 100 generally ok and as important that all cyls. Are relatively close. Be sure when checking compression tohave NO choke and wide open throttle and ignition OFF

. IF IGNITION SPARKS DURING TEST GAS FUMES COULD IGNITE
 
The compression readings are good.

Is there any reason to suspect the engine was overheated? Scorched paint toward the back of the power-head can be an indicator. The paint should be the same color front to back. Black paint is harder to tell. It should have the same shine front to back. I've seen motors overheated so bad it scorched the paint on the midsection.

If you think the engine has been 'baked', proceed with caution.
 

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