How to replace manifold + risers

[natwales]

Engine is a 1988 mercruiser 5.7 raw water cooled sterndrive with about 300 hours and original manifold and risers. I think it's prudent to replace these and I'm curious what is involved. Is it just a matter unbolting and rebolting parts on and off, or is there more to it than that? Can anyone step me throught the process so I can get an idea what is involved and any common misteps in the procedure?<br /><br />thanks in advance

 

[SeaRay24Sorrento]

Re: How to replace manifold + risers

Spray WD-40 on all the bots to be taken off, then go enjoy a cold beer (you may be glad you did). Open petcocks and pull any hoses to let all the water out of the manifolds and risers. Loosen hose clamps on exhaust rubber then remove riser bolts. With some twisting and force they'll come out. Next pull spark plugs so you don't break them off. Loosen all bolts on manifold and maybe place a block under them (they're heavy and awkward). Pull all but the outside bolts completely then last pull the outer. If all went well it should be a snap to put new back in.

 

[Haut Medoc]

Re: How to replace manifold + risers

It's pretty simple. Just like Mr. Sea Ray says.... I like to prop up the front with a piece of wood that fits exactly.....It really helps when re-installing.....I put the riser/manifold together first, so I can stick the elbow in the exhaust boot, it takes alot of the weight off....Then use the stick to prop the front & I start from the front, with the bolts, replace any bolts that are questionable.....Check that your fuel connections have not been disturbed when they were unbolted from the manifold....JK

 

[tommays]

Re: How to replace manifold + risers

if your in the water SINKING is a real thing to watch for when the Y-pipe is open if its to close to the static water line<br /><br />there is a lot of gasket cleaning involved if you dont want leaks<br /><br /><br />tommays