That could be true it's an old hardin tach. I've got a 750 I just rebuilt and put the stock jet size for the carb number in the primary and secondary it's a double pumper w a 6.5 power valve. The timing is set where it seems to be loving the start w out being to advanced and I've barely set the dwell but it runs very strong through out the entire rpm band. I did install a loader and trimmed it flush w the keel.
Dwell?
You have points?
Here's a short list.
I have not seen your boat, nor heard it run so "grain of salt" all of this that follows.
Convert to electronic ignition.
Replace the 6.5 PV with a 4.5
Get your timing assisted for top advance, base is irrelevant to a point.
The engine should be able to make 4,500 rpm without killing itself. Get a quality portable tach. to verify what you have.
GT
