Took my Manifolds and Risers apart….

A quick and good way to check how the whole exhaust system is working is to take every spark plug out and taste it with the tip of your tong (for salt water boats), if you can taste salt you should change it straight away, and it is always good to replace everything and not make the mistake a made to change the manifolds and not the elbows! as I currently have a problem with the elbows letting water in!
 
I would replace them, you have it all apart and you really can't tell what's happening inside.
I got a quote of over 3000 dollars for the Hy-Tek SS setup, a bit to rich for my blood.
after a long and hard search I found a guy in NY that set me up with all new OEM manifolds, risers, and elbows for 865.00 bucks shipped to my door.
They come 2 days later right from Mercruiser. Can't wait to install everything
Oh I have a 7.4L 454 Bravo II
 
This may sound a bit strange to some, but I remove the manifolds and risers every three years - comp[letely disassemble them and take them to a local automotive engine rebuild shop where they get a 'hot caustic soda bath' which takes them down to bare metal, inside and out. They magnaflux for cracks and pits - if all is well, reassemble with new gaskets, some high temp paint and reinstall on the engine, a new thermostat and replace any hoses and clamps that appear questionable and good for another three years. Since I only average 150-175 hours a year (both salt and fresh water) and hardly ever run at wot, I've never had a problem. Since I trailer the boat, and being basically lazy, whenever I use it in salt, I try to stop by the local lake on the way home and run around a bit to flush her out (no mud puddles on the muffs in the driveway that way). If I'm not planning on using the boat for any extended time, I will drain the manifolds and engine (I replaced the drain plugs with petcocks - makes it easy) - makes a difference I think.
 
Guys in over 50 years of fresh water boating I have never seen a manifold or riser rust away. It just isn't mentioned when people talk about boats.
I have personally seen manifolds over 40 years old and in good shape.
Taking that a bit farther the systems in closed cooling that never see salt water will be in even better shape because the antifreeze contains anti corrosion features not found in fresh water lake cooling.
The risers might be another issue and would require a change but its rather cheap.
Once a system has been exposed to salt the rust never stops. You might slow it down a bit but it won't quit.
Doug
 

Forum statistics

Threads
112,942
Messages
1,422,700
Members
60,927
Latest member
Jaguar65
Back
Top