Mercruiser Exhaust risers.

[Benco]

Hi Guys,

I'm in the throws of negotiating my first boat purchase, a 2005 Monterey 218lsc with a 4.3 v6 mercruiser.

I've been trying to research as much as possible about the boat and engine and any common problems that can be prevented.

My question today is about exhaust risers and what measures can be taken to get maximum life out of them. The boat will be drystacked so presumably I would need to flush with fresh water after use? Is this done in the same way as an outboard?
Do you have any other suggestions or recommendations to avoid any issues further down the line?

Thanks in advance.

 

[mlines]

Get a pair of flush muffs that fit onto the sterndrive and flush through after every trip. Some drystack teams will flush for you but not all do. Run some product like "salt away" through the system if it is not being used for a while (winter)

 

[dingdongs]

flush with fresh water if using in the brine every day of use.winterising i remove all water from block and manifolds as air dont freeze.
i would not rely on the single point drains as the manifods do get rust and sand/mud in them so need implement poking through to b sure of water removal.failure to do so is very expensive and only takes 20 mins each winter on a v8.a trailor may be a good investment for working on boat.

 

[Benco]

Thanks for the replies. As I said it will be drystacked so I can have it put on a work rack to make maintenance a bit easier. How often would you expect to change risers/manifold?

 

[dpb]

Thanks for the replies. As I said it will be drystacked so I can have it put on a work rack to make maintenance a bit easier. How often would you expect to change risers/manifold?

If dry stacked and flushed every use 6 to 10 years maybe more. After about 6 years I would remove the risers every couple of years to inspect their condition, new gaskets on reassembly.
If not flushed and used in salt you could be on borrowed time after 3 years.
Just my experience.

 

[Rickard]

If the boat is a 2005 and manifolds and risers haven´t been changed it´s high time to buy new ones
It´s impossible to see the condition from the outside. They can look like new but the inside is pretty much gone.
If these rust to much it often ends up with very big repairs to the engine

Manifold and risers on dry stacked boats has shorter life then compared to boats who live their life in the water