Re: 1980 Mercruiser 470, 3.7L Engine alignment
I also have a 1980 Mercruiser 470 that engine problems. I dropped a thrust bearing bolt into the oil pan, and had a partial seizure. I removed the engine and had machine work done--crank turned and valves ground. Unfortunately, I never got around to putting the motor back together--as I had other boats to use.
I found out this engine originally had been painstakenly assembled--and had different size bearings on the crank--all Ford big block bearings. The head's off a Ford 460 engine. Electrics are GM, as is the carb. About the only thing that's Mercury is the aluminum block and the intake and exhaust manifold.
Are you sure you need an engine rebuild? I/O's seldom need rebuilding due to the minimal "mileage" the engines ever receive. Most engine problems are due to freezing problems, and a 470 is one of the few I/O's with a closed cooling system--not applicable. I do have a full engine gasket kit a reconditioned head and other parts for sale.
If I was going to re-engine a 470, I'd seriously look to EBayMotors.com for a used engine--going for between $900 and $1200.
Pulling the engine is a very easy job. Don't even think about reinstalling the engine without an alignment tool, as you'll burn up the coupler.
The hardest part of your job is installing all new bellows'. You've got to use Mercruiser's bellows cement--a foul, greasy sealant. When you think you've got the clamps sealing the bellows, it'll pop off. I've found this job best handled by the professionals that do them all the time. Unless it's sealed right, water will get in and do damage. It's just not worth the risk and frustration.
