My boat is a 2007 bayliner 325 with a pair of 250 HP GM 350's with 2 barrel carburetors. It may be manifold and riser replacement time. Can any member suggest the better part supplier company to deal with for these items. My engine room is so big that I should be able to tackle this job myself. Your expert suggestions are sure appreciated! Thanks, Griff4
Manifold and risers time!
- Thread starter griff4
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I bought mine from sterndrives.com . excellent customer service and good prices.
CW,
That's just not always a safe assumption. Though exhaust gasses are not as corrosive as in the past, it will still degrade the inner exhaust passage. Always check the wall thickness of the exhaust passage. There are things that affect the mating surface such as the alignment of the risers to the manifold. At the very best, that mating surface is 3/16". When you recognize the manifold/riser joint being the point of failure of most water ingestion causes, it's worth it to be careful when inspecting and making that judgement.
That's just not always a safe assumption. Though exhaust gasses are not as corrosive as in the past, it will still degrade the inner exhaust passage. Always check the wall thickness of the exhaust passage. There are things that affect the mating surface such as the alignment of the risers to the manifold. At the very best, that mating surface is 3/16". When you recognize the manifold/riser joint being the point of failure of most water ingestion causes, it's worth it to be careful when inspecting and making that judgement.
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I agree that there is a potential for failure with manifolds and inspections are required, but generally speaking, from the aspect of rust and corrosion, manifolds should last years.
I once replaced the risers on my boat I had just recently bought. They were original, about 15 years old. Manifolds looked great, also 15 years old.
I once replaced the risers on my boat I had just recently bought. They were original, about 15 years old. Manifolds looked great, also 15 years old.
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Just two suggestions/recommendations for changing the manifolds, regardless of where you buy them. First: Before installation, just run a flat file across the mating surfaces to remove any minor casting imperfections. That will prevent leaks. Second: To ease installation, get two bolts about 1/2" to 1" longer than your manifold bolts.Cut the heads off the bolts. Screw the two studa you've created into two outer mounting holes of the manifold onto the block. Now you can hang your manifold gasket and the manifold while you catch a few of the other mounting bolts. Then remove the studs by hand or with a pair of pliers and finish the installation. That saves your arms from trying to balance the manifold, align the gasket, and catch the bolts at the same time, a PITA. I've used these tricks over two dozen times and have shared them with others. Good luck. Oh, and beware of cheap, Chinese manifolds and risers; they're nothing but trouble. Do a search on the forum for other threads on this. Hy
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One other suggestion...soak all the bolts with PB Blaster or Liquid Wrench and then run the engine. The vibration will help the lubricant soak down into the threads. Do this several times over a week or more. It just might save some busted knuckles.
Excellent advise. Makes the job go a lot quicker and easier.
The other thing I would suggest is to go for OEM manifolds and risers. They aren't too much more money than aftermarket stuff, and I think they last longer.
Mfg recommendation for all threads is Perfect Seal(Mercury Marine/Quicksilver) or Permatex(Aviation)Gasket sealer or a new Permatex "300" that resists anti freeze or detergents in oil. Sounds made for head bolts that go into the water jacket.
Purpose is to seal out air and water, holds bolts against vibration, and non hardening allows easy removal.
Purpose is to seal out air and water, holds bolts against vibration, and non hardening allows easy removal.
I have this job planned for the spring, too. Instead of searching for longer bolts, I bought a foot of 3/8-16 threaded rod from Home Depot. The longest bolts are just under 5" long, so I'll just cut it in half and have two 6" studs to use.
My .02
Thanks, John and others. Who is the better parts supplier to deal with? For quality and price. Send me an email message and I will foward photos of the exhaust setup that I have. Some have said that it's a 14 degree "dry joint" setup. My email: griffi20rb2@gr5tbigplanet.com. Have a fine holiday. Griff4