Re: "Newer" 25/35hp OMC compatibilities

[johnyrude200]

As a follow up, aluminum melts at 1200 degrees F. Using the powers of the interwebs, I see stainless has a melting point of 2700 degrees F. So not to beat a dead horse with a stick…how the HELL does a motor get hot enough to warp one of these baffles if the pistons are aluminum.

I mean, I can buy a 12 x 12 0.06 sheet of stainless steel for $22 (that includes shipping), and manufacture these baffles all day long tracing the original, with peace of mind (which I may very well do for anything in 1976-1978 moving forward). I will get by with my aluminum baffle on my personal motor for this year because I know the motor is right, but as a repair person in business, I will NEVER send out a motor that I think will cause the customer headaches anytime soon.

Shouldn’t the motor seize up well before we hit 1200…or even 2700 degrees F???

Granted in an overheat, we have little to no water supply…but I feel as if the heat thrown by the internal combustion and vented out the exhaust ports would melt the pistons before the baffle ever hit those temps.

I will say that I had a 1969 25hp johnson (my 2nd motor ever…5 years ago), overheat 5x, seize, cool off, and start on the 2nd or 3rd pull within a couple of minutes, so I am extremely sensitive to any motor I work on with respect to the cooling system. It actually melted the top piston off, and it still started on the 2nd or 3rd pull, but after 5 seconds of WOT would lose power and overheat again, even with the melted piston. I think I may actually still have that power head.

I am anal about it quite frankly. And that motor pumped tons of water, and it came out of the blubber hole, and out of the T-stat orifice with the cover off. In retrospect it may have been a clog in the tiny hole in the cylinder head….but nonetheless, cooling systems are things I split hairs with. So getting very familiar with the newer versions of these motors are something I am putting aside a lot of time for in the upcoming months.