Philster
Captain
- Joined
- Sep 15, 2009
- Messages
- 3,344
In a three-way discussion, the issue of manifold and riser replacement in a salt-water boat/engine brought up some interesting perspectives.
My perspective: Replace manis and risers every 3-5 years when used in salt. Go to the higher end if flushing, and stick to the lower end if not. I see this as a maintenance cost. You don't wait for a problem. Like a timing belt on an overhead cam interference engine, you just suck it up and get it done at X hours/years/miles/etc. Cost of ownership, etc.
My marina Merc head tech/mgr: Inspect them, look for signs of trouble, and his inspection was mostly an exterior inspection.
My friend, who wets slips his 5.7/Bravo One: If it ain't broke, don't fix it. Guess who has water on his plugs (I don't know how many plugs)? Bone stock engine. Plugs were being pulled as part of tune up. Engine had no running issues. Started fine. Temp fine under load, etc. Regular tune up showed water on plugs.
I told him the most likely culprits are the manis and/or risers on his 5-6 year old engine/boat. The marina Merc head guy hedged and said it could be one or the other, and they will pull it apart and check.
First, I don't get this, as he implied along the way it could be a hole in a riser. So, he was looking to replace what was broken. Further, could it be a head gasket/seal issue? Never came up. I try to stay out of things because it would be a 3-way issue.
What is the procedure here? Do we all not replace the whole set of mani-riser components? If they don't see anything (can it always be seen???) do you replace anyway and do they then go ahead and check the heads/gaskets/etc?
My perspective: Replace manis and risers every 3-5 years when used in salt. Go to the higher end if flushing, and stick to the lower end if not. I see this as a maintenance cost. You don't wait for a problem. Like a timing belt on an overhead cam interference engine, you just suck it up and get it done at X hours/years/miles/etc. Cost of ownership, etc.
My marina Merc head tech/mgr: Inspect them, look for signs of trouble, and his inspection was mostly an exterior inspection.
My friend, who wets slips his 5.7/Bravo One: If it ain't broke, don't fix it. Guess who has water on his plugs (I don't know how many plugs)? Bone stock engine. Plugs were being pulled as part of tune up. Engine had no running issues. Started fine. Temp fine under load, etc. Regular tune up showed water on plugs.
I told him the most likely culprits are the manis and/or risers on his 5-6 year old engine/boat. The marina Merc head guy hedged and said it could be one or the other, and they will pull it apart and check.
First, I don't get this, as he implied along the way it could be a hole in a riser. So, he was looking to replace what was broken. Further, could it be a head gasket/seal issue? Never came up. I try to stay out of things because it would be a 3-way issue.
What is the procedure here? Do we all not replace the whole set of mani-riser components? If they don't see anything (can it always be seen???) do you replace anyway and do they then go ahead and check the heads/gaskets/etc?