mercruiser 470

:!: I just bought a 1981 Holiday 20 built by Mirro Marine Division that has a mercruiser 1.84 ratio with a 4cyl 470 motor. Can anyone direct me where I can get info on this motor and sterndrive. The boat has been sitting covered for 10 years and I would like to find out what I would have to check or replace before attempting to start it.

 

470

Eh. If my memory serves me correctly it was based on a Ford industrial engine that was in service in the UK in small trucks pumps and so on not a bad engine.

 

The mercruiser 470 is a motor built by mercruiser, with ford parts. They cast there own alum. blocks with liners. They used parts from the 385 series Ford engine ( 429, 460 cubic inch) . The cylinder head, con rods, pistons, rings etc are ford, the exhaust manifolds, intake manifolds and most acc. are mercruiser. You ended up with a 3.7 liter 4 cylinder rated at 170 or 190 depending on carburation. They did have problems with these engines, some people didn't, and I think it was probably cheaper to buy the GM 4.3 to replace there own 3.7 and get rid of there headache. You can go online and lookup the 470 and find what others have had problems with. They are getting hard to get parts for because they have become popular in auto racing . If you go online and look for common problem on a 470 website, it might give you a start were to look and see if you have any of these problems,or not, and see if this is why the boat was not used for ten years.. good luck STEVE

 

Very good summary in last post. I've long been a 470/170 engine fan, in no small part because I'm otherwise all-Ford when it comes to gasoline marine engines.

The short list of common problems:
1. Water leaks in manifold gaskets; all had the problem, not all got the factory upgrades to fix the problem
2. factory alternator system unreliable and very expensive to repair. Kits have been available for a long time to bracket another alternator off a belt.
3. leaks in seal bewtween backside of water distribution pump at cam drive.

The reason they are so popular as cores for the 4-cylinder racing circuits is because they are essentially a lightened 'half' of the legendary Ford 429SCJ..and just as tough.

 

First off I would like to thank you guys for the quick replys.

The reason boat was not used for 10 years is that the owner bought the boat in 97 used it for 2 seasons with no problems, then died that winter so the boat was left unattended as the owners wife had no use for it and so it sat till now. I was able to buy it for a low price.
Seeing that it sat for that length of time I want to find out what I should check (besides just changing motor oil) or do before attempting to start it. I would not want to damage something.