This boat has the 1999 L29 7.4mpi (0L354842). (1999 Sundancer 270 wide with single 7.4 B3) It has always been a freshwater boat.
Today I ran it on the muffs preparing for Spring launch and I noticed very faint condensation/steam coming from the starboard manifold.
It appears to be an issue on the bottom side bend into the front cylinder. There is a heat shield almost right against the manifold because the fuel filter is located below.
This is the starboard side. It appears damp and flaking rust under the front cylinder port with the heat shield.
It looks like it continues to get wet through weeping or perhaps trapping water (can't recall if any openings on the hatch are above). I would guess it has been this way for a long time because the cast iron is really deteriorating and flaking. There is no water or rust on the block. It appears to stay contained in the heat shield area and the bend.
Port side does not look damp or flaky. Possibly replaced as this port manifold has a blue drain plug? The starboard side that is wet does not have a drain plug. Both have the same casting number though.
This is is an unusual spot. Do you think it is a real problem?
Do you think the port side may have been replaced before? I would rather not replace both unless I have to. Again, this is and always has been a fresh water, Great Lakes boat.
When I take them apart, what should I look at?
I have read several threads here about replacing salt water boats manifolds and risers all at 5 years, but freshwater failures are almost unheard of.
I prefer OEM Mercruiser if I have to replace it. Any brands to definitely avoid?
Today I ran it on the muffs preparing for Spring launch and I noticed very faint condensation/steam coming from the starboard manifold.
It appears to be an issue on the bottom side bend into the front cylinder. There is a heat shield almost right against the manifold because the fuel filter is located below.
This is the starboard side. It appears damp and flaking rust under the front cylinder port with the heat shield.
It looks like it continues to get wet through weeping or perhaps trapping water (can't recall if any openings on the hatch are above). I would guess it has been this way for a long time because the cast iron is really deteriorating and flaking. There is no water or rust on the block. It appears to stay contained in the heat shield area and the bend.
Port side does not look damp or flaky. Possibly replaced as this port manifold has a blue drain plug? The starboard side that is wet does not have a drain plug. Both have the same casting number though.
This is is an unusual spot. Do you think it is a real problem?
Do you think the port side may have been replaced before? I would rather not replace both unless I have to. Again, this is and always has been a fresh water, Great Lakes boat.
When I take them apart, what should I look at?
I have read several threads here about replacing salt water boats manifolds and risers all at 5 years, but freshwater failures are almost unheard of.
I prefer OEM Mercruiser if I have to replace it. Any brands to definitely avoid?
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