[markyta]

I have a 2001 Mariah Diablo 180 with a Mercruiser 4.3 V6. It has an Alpha 1/Gen 2 outdrive. The exhaust risers are 1 piece. When I do research for new ones, they all show the 2 piece versions. Does anyone have any info on the difference or compatibility of the two?

Thank you.

[Tlolesen]

I had a 2001 Shabah 182 with the same motor and one piece risers a couple years ago I had water in the oil and turned out the water passage in the port side was leaking, the shop that changed it out put in the 2 piece one's I was told that mercury only did the one piece for a short time and they are known to fail so they recommend to do the 2 piece, I had them do the starboard side the next year just to be proactive.

[markyta]

Thank you for the help. Would you possibly know the part numbers you used for the replacement?

[Tlolesen]

No I don't
The shop that did the install bought everything

[mikeyt]

There is a good thread here on this site regarding replacing the 'batwing' manifolds/risers: 4.3LX Owners, Listen Up