I am in need of everyone's knowledge. I recently bought an almost mint condition Glastron Carlson with an I/O 470 3.7 4 cylinder. Its my first I/O and have only done outboards so far in my boating life but any way since my Baja project is taking so long I picked this up to be on the river this year and not miss another year. So question #1, Can anyone tell me more info about the hull and what the expected MPH should be? #2 What prop was originally on these boats? (the manual says a cleaver style prop but no size.) And last but not least #3 Is there any hi-performance parts available or speed secrets to do to this motor. I've been using the web for info but it is limited. I have converted the points ignition to an electronic ignition and have put some nice plug wires on it. And I also have a 14 1/4 X 19 pitch 4 blade prop on it. Thanks for any info it is greatly appreciated
Great find! That four banger is the only stern drive motor Merc ever made in house. It uses pistons from a 460 Ford with the same stroke as well. About all you can do is enjoy the boat as the motor does not lend itself to mods very well. Some came with two barrol carbs and some with four. You also need to keep a check on the inner cooler. they can get plugged up kinda easy. Lake water does not circulate through the block itself. It is a closed system so antifreeze should be added to the cooling water to prevent corrosion. The motor is a tourque one and does not like high rpm. It is an aluminum block with cast iron sleeves and a 460 Ford head.
Thanks guys for the info!! I guess I'll just have to live with going slower than usual. Hey DB you said something about the inner cooler plugging? Would that be the heat exchanger?? I've seen were some of the owners have changed these to a later years bigger one. Maybe I should put a BB chebbie in it (HA,HA) no I'll just enjoy being on the water finally again!