Bought my self a new gasket and some gasket sealer in preparation and did the work this morning as with the weather being as it was i wasn't going to be doing anything else with the boat!
There were rust stains down below the joint between the manifold and riser so I was worried about leakage into the exhaust chamber.
Splitting the riser away from the manifold was easy, two bolts on the riser and loosen two jubilee clips from the out let side.
Initially they looked a bit messy but once cleaned up looked like this.
Cleaning took a while and you have to be sure to get the old gasket off completely without damaging the metal surface. I used a razor blade scraper which worked well.
As I said, these components are five years old and whilst used in salt water are always flushed after each use when put back on the trailer, except for holidays when the boat has been kept afloat for up to two weeks at a time and not flushed - probably eight weeks in total.
The rust stains turned out to be superficial with no internal leaks apparent. The internal walls of the components still have plenty of thickness and I think they will be OK for a few more years so I will check again in may be three years based on what I found.
If any one has pictures of the same components that have spent a similar time in salt water without being flushed at all it would be interesting to see the difference, though having seen some examples myself (not a pretty sight) I think the pictures show the benefits of flushing.
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