New risers 4.3MPI

shanz_2008

Seaman
Joined
May 19, 2010
Messages
62
Hi
I have two engines merc 4.3MPI 2007on my boat.
I just changed the risers of both engines and on one engine I was not sure that Imade the gasket lip in the right direction so after I stared the engine I took out the grabscrew that it is on the top of the riser and with a torchlight I checked the gasket and it was in the right direction lip facing up.
Wile I was doing the check, noticed that between the lip and the riser there was water so checked the other risers and found them the same. Then I took out one of the risers and confiremed that there was water and only the riser was wet,the extension and the manifold were dry,removed the plugs and there was no water inside.

Has any one encountered this problem because I can not understand from were the water is coming.
Is it possible that it is coming from the elbow that it is after the riser may be I installed somthing wrong?
 

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
71,241
Ayuh,.... Welcome Aboard,.... Are these Mercruiser manifolds, or somebody else's,..??

Did ya clean the gasket surfaces to Clean Metal, before ya put it together,..??

Are they Flat, 'n true,..??
 

shanz_2008

Seaman
Joined
May 19, 2010
Messages
62
No they are not mercruiser but the face is good and there are no leaks from the face for sure.

Before I did the check on the risers I serviced the engins and I changed the fuel filter I didn't know that I had to open the valuve of the fuel ot take out the air so both engins stop ed with out fuel.
Can this be the reason?
 

shanz_2008

Seaman
Joined
May 19, 2010
Messages
62
I think you have turbulators. Which are small lipped gaskets that sit inside the exhaust to catch water that condenses in your exhaust.
Here is a link to some more information....https://www.perfprotech.com/blog/uncategorized/marine-exhaust-turbulators

If found water exactly were it is showing and in my opinion it make sense because I only started then engines for 5 min and when I took out the riser found the extention and manifold very dry and only the riser was wet.

What do you think?
 

NHGuy

Captain
Joined
May 21, 2009
Messages
3,631
Yes, it's OK. the water gets expelled by exhaust the next time you run the engine. The turbulators are there to reduce or eliminate water getting all the way down into the combustion chambers through open exhaust valves while the engine sits between uses.
 

shanz_2008

Seaman
Joined
May 19, 2010
Messages
62
Found the old gaskets of the old risers and the turbulators are full of rust so now I am sure that it is condensation.

Thank you very much for your help.
 
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