mercruiser 2.5L/120 piston ring query

BUTE GOLD

Recruit
Joined
Aug 21, 2005
Messages
2
Hi there,<br /><br />I need a definitive answer to this question: I need a new set of piston rings for a mercruiser 2.5L 120 engine and would like to find an alternative set of rings to the genuine expensive parts here in Scotland, UK. I am led to believe that this engine is a derivitive of a Chev or GM unit. The block has GM stamped on it and the engine serial number is: 2773308.<br /><br />There must be an american car engine somewhere with this unit? <br /><br />Can anyone stick their neck out, based on cast iron experience and tell me what other piston rings would fit this engine?<br /><br />cheers<br /><br />Terry
 

Alumarine

Captain
Joined
Feb 22, 2005
Messages
3,760
Re: mercruiser 2.5L/120 piston ring query

I used Sealed Power rings which is a division of Federal Mogul for my 140.<br /><br />My auto parts jobber looked it up in their catalog under GM marine engines I believe.<br /><br />I also used their gasket set and lifters.<br />I believe they had pistons as well.
 

rbezdon

Senior Chief Petty Officer
Joined
Jun 20, 2004
Messages
689
Re: mercruiser 2.5L/120 piston ring query

I think that "marine" rings are what some autoguys used to use for heavy duty racing and I think they were called Crome Molly. A harder ring for higher temp and stress and not just the common Chevy II rings.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: mercruiser 2.5L/120 piston ring query

I think the part number was the same as the 307 chevy V8 as well as the 250 CID inline 6. was really nothing special about the pistons,rods, bearings or rings in the old 153 motors. depends on how much ya wanna spend. look up the ring specs and the piston ring groove and land specs and you will find what ya need.
 
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