Manifolds/Risers

[Cool It]

I have a 2000 24 foot searay -5.7 EFI Mercruiser Bravo 2 I have not replaced manifolds and risers -I bought the boat in 2005 prior to that it was in Brakish water up on the hudson.The boat has been running great- temp is fine and running smooth. Will there be any tell tale signs that my manifolds and risers are ready to be changed out or will they just go on me -and if they go what can happen to the engine.

Thanks
Cool It

 

[HT32BSX115]

Re: Manifolds/Risers

Howdy,

Will there be any tell tale signs that my manifolds and risers are ready to be changed out or will they just go on me -and if they go what can happen to the engine.

Not always.

Saltwater manifolds and risers if left long enough will sometimes clog with rust such that one side will start running hotter than the other and/or will clog enough to cause over heating at progressively lower and lower power settings (if the water cannot get out the engine will overheat)

Also, if the risers have not been removed and inspected (probably every 2 or 3 years or so in salt) and new riser gaskets installed, you could get leaks into the exhaust area which would damage the engine fairly quickly.


When you DO remove the risers you inspect them at the sealing surfaces and internal area you CAN see for rust.

If you have a 2000 boat with original exhaust manifolds and risers you should consider removing them, inspecting carefully and plan on replacing them if there's a question.

NEVER wait for symptoms of cooling system problems in a salt water engine!!

"Preventive" maintenance in a salt water engine will help prevent engine destruction due to a riser or exhaust manifold failure.

(is this a "closed-cooled" engine?)


Cheers,


Rick

 

[Cool It]

Re: Manifolds/Risers

Ok thanks -I guess I better take care of this -is this something the average guy can do with not much mechanicak ability or do u recommend a mechanic -I also have extension blocks between manifolds and riser does that make it any more difficult

Thanks
Cool It

 

[IES99]

Re: Manifolds/Risers

Ok thanks -I guess I better take care of this -is this something the average guy can do with not much mechanicak ability or do u recommend a mechanic -I also have extension blocks between manifolds and riser does that make it any more difficult

Thanks
Cool It

If you have twisted some wrenches in your life, you can do it. You can do it and have the satisfaction of doing it yourself.

 

[HT32BSX115]

Re: Manifolds/Risers

Ok thanks -I guess I better take care of this -is this something the average guy can do with not much mechanicak ability or do u recommend a mechanic -I also have extension blocks between manifolds and riser does that make it any more difficult

Thanks
Cool It

Pulling manifolds, extensions and risers is pretty easy. .... a few bolts and studs etc.

The extensions are no different. They are though, another source of possible clogging with rust since ALL the cooling water that passes though the engine and manifolds MUST exit up though the extensions and risers.

In a RAW WATER cooled engine, if your manifolds, risers and/or extensions are clogged with rust, it'll be time to replace them. don't try to "clean" them.


Regards,


Rick

 

[Cool It]

Re: Manifolds/Risers

thanks for the input -might try myself -do u think im ok with after market manifolds and risers ? not sure yet from who or where.

 

[zbnutcase]

Re: Manifolds/Risers

Pay a good shop to do it. I have seen plenty of engines ruined by DIYers not getting things sealed properly!