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-   -   Converting auto engine to marine (https://www.offshoreonly.com/forums/general-q/285321-converting-auto-engine-marine.html)

notfastenuf 09-23-2012 06:51 PM

Converting auto engine to marine
 
What all needs to be changed to convert auto motor to marine

cliff_m_b 09-23-2012 10:34 PM

Brass f\Freeze Plugs, Stainless Steel Head Gaskets, Marine Water Pump - (has brass impeller), and Water Cooled Exhaust Manifolds I believe are the main parts, if you truly want a good marine motor replace the exhaust valves with inconel

Cliff

the deep 09-23-2012 11:05 PM

You'll need a cam change and depending which engine you have maybe more to make it live in a marine application .

sprink58 09-23-2012 11:16 PM

I addition to all the GOOD answers above...a marine starter, distributor and alternator. The distributor for a car has a different advance curve than that of a boat and the starter as well as the alternator should be USCG approved for spark resistance plus the fact that they are designed to be used in a severe marine environment.

notfastenuf 09-24-2012 07:41 AM

Thanks for all the info u guys are alot of help

notfastenuf 09-24-2012 07:45 AM

Do the auto part store carry some of this or just better buying from a boat store any suggestions

professor_speed 09-24-2012 08:12 AM

Oreilly can get stuff from sierra marine, and Wilson (starters and alternators) that should cover most everything you need. id it a common engine? American V8?

1987pachanga22 09-24-2012 09:44 AM

Napa also has some of the parts. What engine are you converting?

notfastenuf 09-24-2012 10:24 AM

Would be building a Chevy 454 possibly

billy boats 09-24-2012 12:12 PM

Marine engines and car engines are different internally . All if the clearances are different for marine application. Rod and main bearing clearance is larger for marine use. Also piston to wall and ring end gap are different . It makes a big difference if you want an engine to live in a marine application .

Jason3603 09-24-2012 01:25 PM


Originally Posted by billy boats (Post 3783220)
Marine engines and car engines are different internally . All if the clearances are different for marine application. Rod and main bearing clearance is larger for marine use. Also piston to wall and ring end gap are different . It makes a big difference if you want an engine to live in a marine application .

A 97 Merc 7.4LX and a 97 7.4 GM truck engine (both TBI) run the same clearances according to their shop manuals. I am certain this is an exception. These engines do not make much power at all. When it comes to making big HP the clearance are definitely different.


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