Opinions on manifolds and risers

Mad Props

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I think I already know the answer but what are the experts thoughts on the condition of these? The risers are pretty rough at the elbows but the manifolds actually don't look horrible to me but I assume they are the same age.
 

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achris

More fish than mountain goat
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Clean the gasket surfaces and show us again.... Can't see anything under the muck.
 

tpenfield

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^^^ Agreed. Clean everything up. Bang the rust scale out of the nozzle portion and see what you have. Might not be too bad.

Are you in salted or unsalted water?
 

Mad Props

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I'll clean em up later and snap some more pics..

I boat in fresh water but the previous owner was in brackish (upper Chesapeake)
 

Bondo

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I'll clean em up later and snap some more pics..

Ayuh,...... Long strokes with a flat file on the gasket faces,.....
 

jws123

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Wouldn't risk it any boat i get unless the risers look brand new i change them its worth the $600 rather then being out 1 day and blowing up your motor.
 

achris

More fish than mountain goat
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Does new risers not also mean new manifolds?

Not necessarily. I put new elbows on my engine about 6 years ago. Manifolds were still in excellent condition, so they stayed.

The 'pointy end' of your elbows look ok, but it's the gasket surfaces we're most interested in. Once you clean the gasket material off them (both elbows and manifolds), use fine emery on a brickie's float to 'polish' the surfaces. What you are looking for is good shiny metal all the way across. If you see dull grey metal between the exhaust cavity and the water jacket cavity, that's compromised metal, and time for the rubbish bin...

Chris......
 

Lou C

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Agreed I'd clean up the mating surfaces and make sure you have good clean flat metal there, use a straight edge and feeler gauge to make sure its flat to less than .003". The water passages in the manifolds and elbows don't looked clogged by rust but I'd replace the elbows given what the part aft of the hose connection area looks like. Looks like you got chunks of cast iron coming off of them. So you might be able to re-use the manifolds and replace the elbows....
 

Mad Props

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Got them cleaned up but forgot to snap a picture... manifolds actually look really good... not convinced the risers are salvageable... the mating part seems okayish but I just cant get past the coupler end... it's just flaking apart
 

Mad Props

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Decided to bite the bullet. Placed an order for 2 new OEM risers (didn't spring for dry joints cuz my manifolds look like they have quite a bit of life left). I'll still try to remember to post some pics of the manifolds tho. Taking them completely off anyways to clean up/touch up the paint...
 

Lou C

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Sounds like a good plan, the outlets on your old elbows had rust chunks falling off and were not long for the world. Last thing you want is a season from now it rots through under the hose and then it starts pulling water back in. Next is rusty exhaust valves...
 
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