Leaking Exhaust manifold risers (Commander)

[OHskier]

Hello. I have a '87 Skier that seems to experience escaping exhaust around the top half of the exhaust riser. The riser in that area becomes extremely hot and the boat has gotten a bit louder. A replaced gasket did not solve my problem and a visual inspection of the riser does not indicate any cracks or compromise. Is this a manifold problem or something else?? Any suggestions would be greatly appreciated.

[eyepeeler]

Check your impeller, make sure the engine is cooling. Check tranny cooler.

[OHskier]

Check your impeller, make sure the engine is cooling. Check tranny cooler.

The boat seems to be cooling just fine. It's just the riser that seems to be smoking and getting hot. It's showing exhaust carbon on the outside where the leaking seems to be occurring....Thanks

[footnlongline]

The boat seems to be cooling just fine. It's just the riser that seems to be smoking and getting hot. It's showing exhaust carbon on the outside where the leaking seems to be occurring....Thanks

If it is getting hot, the water passages are clogged.

[JasonK]

My guess would be that the cooling passages are blocked. Replace the manifold for $125.

[OHskier]

My guess would be that the cooling passages are blocked. Replace the manifold for $125.

Thank you for your post. I'm guessing you're thinking my manifold is coroded, causing the cooling passages to clog. Should I try a fresh water flush first or maybe check the termostat housing? Again, the boat is not overheating and the hot riser exist only on one side...

[footnlongline]

Thank you for your post. I'm guessing you're thinking my manifold is coroded, causing the cooling passages to clog. Should I try a fresh water flush first or maybe check the termostat housing? Again, the boat is not overheating and the hot riser exist only on one side...

You have blockage in the manifold or riser, not the thermostat housing. You can pull the riser and manifold and run a wire through the passages to clear. you may have gasket material causing a partial blockage as well. If you pull your manifolds, pay attention to the exhaust ports, there should be no rust present, if there is rust, that is a indication of failure and you should replace manifolds and risers.