nowhere near the same motor.
also, what does your 470 have to do with the OP's issue of no spark?
Their ignition systems are nearly identical, points ignition system, single ignition coil, with a distributor that has mechanical advance. They both have a mechanical fuel pump. They also both have 2bbl carbs. The idle speed setting, fuel mixture setting , and idle rpm range are all the same. The timing is also the same for both engines as they have both been changed from 8 deg btdc to 4 btdc as per the Mercruiser Service bulletin. So I would have to disagree that they are “no where near the same engine”. And if you read what OP said, he has told us that he ASSUMED no spark, therefore he doesn’t know for sure; so I was providing a solution that fixed a similar no start problem with an arguably similar engine. The fact that he has told us that his engine starts after trying many, many times tells me that he isn’t getting “no spark” because clearly it is starting sometimes. A flooded engine would present a similar issue as an engine with “no spark” would. OP could hold the spark plug in his hand and place the metal part on the engine while cranking to see if he sees a nice thick blue spark to test for spark.
