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-   -   What's the difference between GM Marine Engines & Mercruiser? (https://www.offshoreonly.com/forums/general-q/222923-whats-difference-between-gm-marine-engines-mercruiser.html)

Tow-N-One 01-18-2010 11:10 AM

(speed=$$$)-relaiability

Bad Girl 01-18-2010 11:19 AM

Merc
 
From what I have learned the "hand built" starts with the 575. The 500 and 525 are base engines built by GM for Merc.

getrdunn 01-18-2010 11:25 AM


Originally Posted by Tow-N-One (Post 3026326)
(speed=$$$)-relaiability

How true...

1BIGJIM 01-18-2010 12:11 PM

It's amazing how these threads get so far of topic. My question did not have anything to do with 700Hp engines or $$$ equal speed. Nothing I don't know already.

I thought someone might know the answer to the question.

I stopped in at my Mercruiser dealer because I get a 15% discount. They could only find one 502 in stock, and that was in Atlanta Ga, and it was much higher priced than the GM Marine engine. I don't know if Mercruiser buys the exact same engine and increases the price 2K.

I guess its time to put this thread to bed.:lolhit:

Raylar 01-18-2010 12:34 PM

JIM:

To help with your question on almost all engines marinized by Mercruiser at StillWater Oklahoma, not Mercury Racing at Fond du Lac, Mercury takes standard GM built base long block engines and they order them with sometimes a different camshaft profile for marine, brass freeze plugs and certain other heavy duty timing chain components, etc. Mercury then finishes the marinization with their alternators, pumps, cooling system, oil filter and cooler system, induction system, electronics, mounts and brackets etc. Mercury also tests and makes sure the finsihed complete engine is correct and running as it should However, on short or long blocks from Mercruiser you are not getting this testing and Mercury relies on GM's OEM warranty to back their parts warranty.
By the way which engine are you replacing the block on as certain Mercruiser offerings had upgraded forged pistons and crankshafts supplied by GM versus cast components?

In any event if you purchase a GM powertrain MARINE, that's an important distinction! short or long block from an approved supplier who honors his and GM's parts warranty you should in most cases receive a piece comparable to the Mercruiser part if the horsepower and application numbers match. THIS DOES NOT apply for automotive replacement short or long blocks and even GM's literature states on those units "Not for Marine Use!"

Hope this helps to dispell some of the incorrect info that floats around on this subject.

Best Regards,
Ray @ Raylar

Velocity Vector 01-18-2010 12:40 PM

I have heard the tolerance's are checked closer in Merc motors and have heard advise you should take a gm motor to a reputable builder have all the specs checked just to be on the safe side if you want to spend a little extra for piece of mind. I know one more thing Merc or GM I have broken both. If your not looking for anymore than 415 hp I'd just stab the GM motor and go boating. Boats with genuine Merc motors might sell easier at a premium but in this market who's selling anyway?

Uncle Dave 01-18-2010 12:42 PM

Curious
 
A plethora of good inf as usual Ray.

What does GM ask for the "Hecho en Mexico LSA engine"?

To get it into the boat would be this # plus accessories plus exhaust. does a regular exhaust set up designed for 23 degree sb chevy stuf bolt right up?

HOw did GM get the dyno number- through marine headers or dry exhaust I wonder..


Uncle Dave


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