Need info on a 28hp mariner

[FinaddictMike]

Picked up a 28hp mariner model 664 452523 with a made in Japan sticker on it. Anyone got manuals or something to tell what year it is? I'm guessing its a 1979 or there abouts Yamaha made for mariner. There is hardly any info at all on the internet on these mariners. I'm wondering what the correct plug is (it's got champion in it now-I despise champion plugs in an outboard), what gap, impellor kit and whatever else I can find out.

[bottom scratcher]

Picked up a 28hp mariner model 664 452523 with a made in Japan sticker on it. Anyone got manuals or something to tell what year it is? I'm guessing its a 1979 or there abouts Yamaha made for mariner. There is hardly any info at all on the internet on these mariners. I'm wondering what the correct plug is (it's got champion in it now-I despise champion plugs in an outboard), what gap, impellor kit and whatever else I can find out.

Mike,
I'm not totally positive but most of the smaller engines made for Mercury/Mariner were made by Tohatsu but maybe the older one's were Yamaha. Good Luck.

Spark Plug B-7HS (NGK) .027" (0.7mm) Gap

Impeller Mercury part #47-84797M ( Pump Assembly is no longer available)

Here is the Mercury parts listing:

http://www.mercruiserparts.com/selectDocs.asp?doc_nbr=83008

[FinaddictMike]

You found more than I did, thanks. Yeah it's Yamaha manufacture.