"I have a restored 1984 Harris
"I have a restored 1984 Harris 28' pontoon boat powered by the original OMC 120 (GM base 4 cyl) I/O. It runs, at best, 18 mph. The engine has a lot of blow by and rather than overhauling the 120, I am seriously considering changing the driveline over to a Mercruiser 470. The 470 would give me additional power, and the ability to trim up the outdrive whereas the OMC drive knuckles will not. I am wondering if the 470 will fit into the space (aluminum pod) the 120 is in, and if anyone has an opinion about the comparison of maintenance requirements of 120 vs 470. I can do the swap myself including welding the aluminum. I'm just looking for more power with ease of maintenance and good durability. Your opinions are appreciated."
"I have a restored 1984 Harris 28' pontoon boat powered by the original OMC 120 (GM base 4 cyl) I/O. It runs, at best, 18 mph. The engine has a lot of blow by and rather than overhauling the 120, I am seriously considering changing the driveline over to a Mercruiser 470. The 470 would give me additional power, and the ability to trim up the outdrive whereas the OMC drive knuckles will not. I am wondering if the 470 will fit into the space (aluminum pod) the 120 is in, and if anyone has an opinion about the comparison of maintenance requirements of 120 vs 470. I can do the swap myself including welding the aluminum. I'm just looking for more power with ease of maintenance and good durability. Your opinions are appreciated."