Mercury 5.0l EFI cracked block

[aforrester20]

I have a Mercury 5.0l EFI that I forgot to winterize. The block and Exhaust Manifold have cracked. can i replace the block with a automotive block and if so what block do i need.

 

[Scott Danforth]

Same year truck block and heads. You will need yo change the core plugs to brass and the head gaskets to marine.

You will need a new marine circulation pump, new intake and new exhaust

 

[aforrester20]

is the block a 350 chevy

 

[Rick Stephens]

Your current block is a 305 Chevy.

 

[Scott Danforth]

More parts to change to go to a 350. Best bet in that case, get a complete 350 with ECU

 

[aforrester20]

Would it be easier to just get a chevy 305

 

[tpenfield]

Would it be easier to just get a chevy 305

Yes. 5.0 liters is the GM 305 block. Use the numbers on the existing block and heads to find a suitable match.

 

[Bondo]

Would it be easier to just get a chevy 305

Ayuh,...... A new long block from yer local GM dealer is under 2 grand,....

 

[aforrester20]

Will the exhaust manifold fit on the chevy 305

 

[Bondo]

Will the exhaust manifold fit on the chevy 305

Yer motor IS a Chevy 305,....

 

[tpenfield]

To Bondo’s point, Mercruiser and Volvo-Penta get their base engines from GM and then add their fuel, ignition, and exhaust systems to the GM engine.

in the last couple of years mercruiser has introduced their own engine not based on an automotive engine (4.5 L)

 

[Scott Danforth]

Will the exhaust manifold fit on the chevy 305

are you not reading the replies? you have been given the answer multiple times

lets educate you on the GM small block chevy

5.0 IS 305 cubic inches
5.7 is 350 cubic inches

all small block chevy engines have the same exterior dimensions. so the exhaust manifolds will fit any small block head from 1957 to today from any displacement of 265 cubic inches to 434 cubic inches

you have a 5.0 EFI which is 305 cubic inches. the bore is 3.736" and the stroke is 3.48" due to the small bore, the heads are 5.0 liter specific (smaller combustion chamber, smaller valves, smaller intake plenum size). however the exhaust ports are the same

 

[aforrester20]

Thanks guys.

 

[Lou C]

and then add a heat exchanger to your new engine so you never have this problem again. IMHO all cast iron inboards should be closed cooled. Raw water cooling works but its risky unless you are going to always going to winterize on schedule...I would never install a new engine without closed cooling....

 

[garbageguy]

When using numbers, always consider the unit of measure any number is representing. 5.0 Litres, is about 305 cubic inches