Re: tower of power info
Hi,
The 1978 140 was right before they left the Distributor ignition to go to the ADI system that used two switchboxes and separate coils for each cylinder. So; you want to decide which ignition system you'd rather have. They switched in mid-production in 1979 is I remember correctly.
I just had the opportunity over the weekend to view a '78 and a '79 side by side with the cowling removed. Wow! I'd forgotten how simple (comparatively) the older ones were. That big ol' distributor in there...but a LOT of open space everywhere. The newer ADI model is crammed full of wiring and electronics.
As with any old Merc like that; be prepared to re-wire internally if it's not already done. Check the wiring carefully before you even go so far as to hook a battery up.
All in-lines are very sensitive to good carburetion and cooling. Don't run one without being certain that the carbs are clean and the impeller is fresh and the cooling passages are clear.
Chuck