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Manifold & Riser replacement?


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Experts,

I just had my boat winterized, oil changed, and shrink-wrapped. I've been using the same guy for 4 seasons, and I trust him. When he went to remove the oil filter, it was melted to the block (the rubber seal melted - not the metal fitting). It took him 90 minutes to get the thing off without resorting to brute force (I would have resorted to that after 5 mins). I should snap a picture of what's left of it... totally mangled.

Anyhow, once he got the oil changed he started the boat (hooked up to a hose) to see what's what. He observed normal engine temp, and normal temp at the thermostat. Manifolds were too hot to touch, though.

So, his diagnosis is either 1) bad impeller so restricted water flow, or 2) manifolds are restricting water flow and need to be replaced. I just replaced the impeller 2 months ago, so I don't think that's it. Also, when he did my service at the end of last season he made the same note about manifold/riser temp being too hot. At that time he noted the hoses were partially kinked, and we chalked it up to that and I replaced them in the spring.

What do you guys think? Do manifolds/risers need to be replaced after some time (mine are 16 years old)? I'm inclined to hit Bakes/eBay to find parts and get this repair done over the winter. (Same mechanic says he can come out if it's not below freezing, cut open shrink wrap, make the repair, patch the wrap at a discounted labor rate since it'll be off-season. If I wait until spring it's the full rate.) Given that the oil filter got so hot it melted, I'm not inclined to tackle this seemingly easy repair myself... I'll bet those suckers aren't going to come right off like they should if they've really been running that hot.

2000 Sunsetter Lxi

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No expert, but I'll take a shot...

2 hours ago, slap said:

Experts,

I just had my boat winterized, oil changed, and shrink-wrapped. I've been using the same guy for 4 seasons, and I trust him. When he went to remove the oil filter, it was melted to the block (the rubber seal melted - not the metal fitting). It took him 90 minutes to get the thing off without resorting to brute force (I would have resorted to that after 5 mins). I should snap a picture of what's left of it... totally mangled.

Anyhow, once he got the oil changed he started the boat (hooked up to a hose) to see what's what. He observed normal engine temp, and normal temp at the thermostat. Manifolds were too hot to touch, though. I don't think this is all that unusual, even with everything functioning properly.

So, his diagnosis is either 1) bad impeller so restricted water flow, or 2) manifolds are restricting water flow and need to be replaced. I just replaced the impeller 2 months ago, so I don't think that's it. Brand new impellers have been known to be defective. (e.g. rubber separates from brass center) But since the engine and thermostat temp checked out, the impeller is probably okay.  Also, when he did my service at the end of last season he made the same note about manifold/riser temp being too hot. At that time he noted the hoses were partially kinked, and we chalked it up to that and I replaced them in the spring.

What do you guys think? Do manifolds/risers need to be replaced after some time (mine are 16 years old)? YES! The risers & manifolds are cast iron and have a limited life. Corrosion can cause them to spring external leaks and also cause the water passages to become plugged. I'm inclined to hit Bakes/eBay to find parts and get this repair done over the winter. (Same mechanic says he can come out if it's not below freezing, cut open shrink wrap, make the repair, patch the wrap at a discounted labor rate since it'll be off-season. If I wait until spring it's the full rate.) Given that the oil filter got so hot it melted, I'm not inclined to tackle this seemingly easy repair myself... I'll bet those suckers aren't going to come right off like they should if they've really been running that hot. They will probably come off easier than that rubber oil filter gasket.

2000 Sunsetter Lxi

Keep us posted, as this is something I may be facing soon.

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OK, so John's reply jives with what my mechanic says... looks like I'll soon Bust Out Another Thousand.

Would anyone happen to have part #'s for a 2000 Sunsetter LXi?

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The oil filter gasket being basically stuck isn't all that unusual.  I just twisted one in half last week because it didn't want to come unstuck from the remote filter mount.  Not sure what the deal is with boats, but I've had that problem on a few filters that I personally hand tightened when they were installed.

 

I'd make sure that the manifolds are actually hotter than they should be.

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Just now, Steve B. said:

Hm, how much water was coming out the exhaust as he was testing?

Steve B.

Normal amount, though he noted that he had the hose directly connected to the inlet (instead of via a fake-a-lake) so the pressure of the hose may have helped.

I'm catching the vibe that I should jump the gun on this one... perhaps I should wait for spring and use my heat gun to get temp readings out on the water. Based on oldjeep's reply, I may also get in the habit of turning my filter an 1/8 of a turn and back every so often during the season. 

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