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1970 40hp Compression ???

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SkipperC

New member
I just bought a little boat that has a 1970 40hp BIG TWIN ELECTRIC Lark. I ran a compression check on it and it has 70lbs on both cylinders is that right for this small engine. I thought it should be around a 100 or so. thanks
 
Got a new battery this morning and installed it. I ran another compression check using the battery and not the pull rope. Got a better reading. shows 80lbs on both cylinders now. When I pumped the bulb to get fuel pressure it ran out the front of the carb but stopped. It cranked over and started and would run but it pops out the exhaust and when I try to give it gas it dies. So do you think it's in the carb or the spark plugs need to be changed. TIA.
 
Sorry you meant both plugs and carb. Got it. I will see what I can do about it. If I can rebuild a Quadrajet on a chevy I should be able to rebuild this carb.
 
Put the new points and plugs in. Took the carb off and it is clean. Looks like someone put a new one on it. Got it to start. It SMOKED really bad at first but after it ran for a while it stopped smoking so much. the water pump works. It still has a little bit of a miss every couple of seconds. Could it be the points are not set on the money. I set them on .022 as it says in the book. But it does run. That's good for now. Now to start on other things. Like the steering cables being replaced. That should be fun.
 
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