racerone, thanks for the heads up. glad to find that out before i started drilling anything. i can't find an orifice chart for this era 70hp anywhere, if you have any advice on what altitude adjustments are appropriate, i'd appreciate it.
pending other input, since it runs fine at idle I might...
based on parts diagrams, various research and the info at the beginning of the thread i have no reason to think that it isn't... the 54D idle air orifice is at the top of the carb, the 32 fuel orifice is in the fuel bowl.
i'm not a complete noob to engines, I own a lot of old stuff but you...
yup, I pulled them to check. the only chart I can find is for 85hp and up, it lists 58/30 orifices for air/fuel on the 85hp so 54/32 on this 70hp seems to be in the ballpark. regardless it runs great at low altitude so I'm ok with using them as a baseline. that said if you have any better...
the image didn't seem to attach right so here's a direct paste on the #s
starcraft evinrude 70 alt adjustments
dia
area
area change
equiv dia wire
air bleed
sea level to 3000
54
0.055
0.00950
air bleed
3000 - 6000
52
0.0635
0.01267
diff 54 to 52
0.00316...
I'm going to resurrect this very old string because I'm having the same altitude issues on my '78 Evinrude 70HP outboard. I can't find orifice charts for that specific motor but it has 54D air bleeds and 32 fuel jets and it runs great at sea level. I live in the foothills and regularly visit...