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1994 Mercruiser 3.0 Ltr GM Engine

KEWeyand's Avatar

Join Date: Oct 2002
Posts: 44

05-11-04, 12:35 PM   #1  
1994 Mercruiser 3.0 Ltr GM Engine

I find I need to replace this engine. Is there any reason why I can't replace it with an engine out of an automobile? Can it be adapted to bolt up to the outdrive? The marine application engines are very expensive and I'd like to keep the cost down if possible.

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jughead's Avatar

Join Date: Oct 2003
Posts: 597

05-11-04, 07:20 PM   #2  
Yes, you can use an auto engine in marine applications. A chevy small block will work nicely. However, there are a few things to consider. You must use a marine type carburator to meet Coast Guard rules. There are also a few other things to consider. A marine engine is usually a little heavier duty because the engine works a lot harder in a boat that it does in a car. Using a stock cast crankshaft would be unfavorable. You would do better with a forged one. A stock cam shaft would also be unfavorable and you would be a lot better off with cam ground for marine service. There are some cooling system considerations as well. In other words, yes, you can indeed, power your boat with a Chevy (or Ford) auto engine, but it would be better if you really knew what you were getting yourself into before you attempted the job.
There are a lot of things to consider and if you don't have most of the skills necessary to do the work it will probably cost you more in the long run than just getting a replacement marine engine and bolting it in.

Ed Imeduc's Avatar

Join Date: Aug 2002
Posts: 18,389

05-12-04, 10:48 AM   #3  
Look around are ask around for a marine short block for what you have there .Most of the time they will make an exchange. You strip the old parts carb, man , alt,dis,off and use them on the new short block. They do this with gas or diesel engines. Also I dont think any of the car engines have a place to put engine zincs in them


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