5.0L EFI new exhaust manifolds + spacers + risers

GoFastr

Cool Runnings
Jan 20, 2016
165
Cayman Islands
Boat Info
2003 Sea Ray 270 SunDeck MX 6.2L MPI w/Bravo III
Tow: 2012 Ford F150 Raptor SVT
Engines
Mercruiser MX 6.2L MPI w/Bravo III
I never noticed an overheating problem before but when running the boat on hose muffs in the yard before going out I saw water coming from the drain plug and wondered why water was coming out of the boat when it had been kept covered and hadn't been in the water for a month. I investigated and found the leak to be a hairline crack in the exhaust manifold by the elbow that the hose connects to. It seemed that when it got hot it would expand and open up causing a leak inside the boat. Lucky I caught it before going out to sea!

So I just recently purchased new exhaust for my 1998 Sea Ray 210 Sundeck with 5.0L EFI and Alpha One Gen 2 sterndrive.

I also purchased all new hoses that carry water including a new thermostat and the impeller kit for the sterndrive. I am determined not to have any cooling issues.

My boat is wet style exhaust, raw water cooled with no heat exchanger.

My question is, which gaskets do I use between the top and bottom of the 3" spacers?

Riser elbow
|
Gasket (Restrictor type -OR- Open?)
|
3" spacer
|
Gasket (Restrictor type -OR- Open?)
|
Exhaust manifold

My parts came with a variety of gasket types and configurations and I'm not sure which ones to use where for my very hot and humid tropical climate. I never have to winterize my boat.

Thanks in advance!
 

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I would put it back together the same way it was when you took it apart, paying close attention to the location and type of gasket removed.
 
Yeah, I wish I had the old exhaust to see now.

I just unbolted the exhaust manifolds from the engine and took them off in one piece.
I gave them to the junkman and never unbolted the risers and spacers.
 
Serial number of engine will help figure it out but, how many hoses feed the exhaust on each side and where do the connect? Single hose from tstat housing to bottom of manifold?
 
Serial number of engine will help figure it out but, how many hoses feed the exhaust on each side and where do the connect? Single hose from tstat housing to bottom of manifold?
Serial number is L329549.
Each exhaust manifold only has one water hose coming from the bottom of each side going to the t-stat housing.

As far as I know everything is OEM and this may be the first time they have been replaced. Engine has 553 hours.
 
I don't think thats a merc serial number, but I could be wrong.

Anyways, with a single hose feeding the bottom of the manifold I believe you need the 4 slot gasket. See the attached exhaust bulletin PDF. I used that bulletin as a guide on our 98 5.7EFI's and all has been well for 3 years.
 

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OK great. Many thanks!

So it looks like I have to use all of the 4 slot type gaskets then for my setup.

BTW...the hull is a 1999 but the engine serial number comes up as a 1998.
 
Last edited:
Thanks all. Got all the parts installed and no more leaks! Life is great again.
 

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