The old non-OEM manifold & riser leaked causing a valve to freeze up resulting in a bent push rod. The heads were rebuilt and now I need to replace the exhaust manifold & risers. The engine is a raw water cooled 1995 4.3 Mercruiser used exclusively in salt water. There's a big price difference between OEM vs. Aftermarket. Any experience with Barr, GLM, Sierra or other after market brands?
OEM or Aftermarket Exhaust Maniold & Risers?
- Thread starter seachunk2
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What brand and how old where the ones that failed?
I bought a GLM elbow once for my 3L Mercruiser and it had some slag inside the water jacket that made the engine run hot. I had to take it off to see what was wrong and saw it. Was able to clean it out and then all was good.
I'd lean toward OEM where available. You don't do this work often, the labor is a pain and/or expensive, and the consequences of failure are potentially very high. Why not get the best?
I'd lean toward OEM where available. You don't do this work often, the labor is a pain and/or expensive, and the consequences of failure are potentially very high. Why not get the best?
- Joined
- Jun 4, 2001
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I go with OEM. You get what you pay for in risers.
As I mentioned in your other post about gaskets, it's the width(thickness) of the wall between the exhaust and water jackets. If you can, you can do a test to check between brands. Get a file to clean any flashing that may be protruding into the jackets and measure the wall thickness. If you have the time, Move the cast pieces forward and back and see how much movement between each piece. The amount of movement reduces the surface area to be torqued by 2X.
Most of the manifolds have been manufactured by the same foundry. Not sure where the machining is done. Right now, I have GLM aluminum exhaust manifolds on my 406ci SBC. No problems so far in salt water but she sits on a trailer between fishing trips.
Most of the manifolds have been manufactured by the same foundry. Not sure where the machining is done. Right now, I have GLM aluminum exhaust manifolds on my 406ci SBC. No problems so far in salt water but she sits on a trailer between fishing trips.
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I replaced manifolds, spacers & Risers on both my 6.2L mercs this spring. I bought the kits from BARR, Quality seems good, make sure you use the better gaskets and make sure mating surfaces are flat & clean. hopefully i wont know for 4 years how long they last.. that is my scheduled change interval since the motors are FWC, however my exhaust is RWC and im in saltwater