Hi All,
Last April my partner and I purchased a complete"new" re-manufactured 4.3 liter Mercruiser engine to replace the toasted one in out boat....we purchased it through a Mercruiser dealer who installed it. We also had them install a full fresh water closed cooling system that was less than a year old that had been installed on the old motor shortly before it failed. A month after they completed the work we noticed coolant level was dropping in the reservoir. The engine was hard starting and steamed badly and smelled like coolant. We brought it back to the dealer and he discovered that the gasket for the blanking plate at the riser manifold had failed accounting for these problems. Since then it has failed two more times and he has tried two other sets of gaskets..He assures me the mating surface of the riser and blanking plate are flat ... and no cracks can be found on the riser (the failure is on both manifolds)...What we noticed is that after the gaskets are replaced the leaks are gone but after a period of time a couple months the leaks return. He says when he takes the risers apart the gaskets look like they are deteriorating. He uses a mercruiser coolant that is reddish in color. Now he thinks maybe this coolant is attacking the gaskets and causing their premature failure.
I was wondering if anyone else has experienced this issue or has some ideas on what else might be going on. I am a mechanic by trade and trust the guy doing the work he is a long time mercruiser dealer/owner and highly rated. At this point he is thinking we should try replacing the gaskets again (he has tried several different manufacturers) but he thinks we should try the green automotive coolant instead.
Thanks ahead of time for your thoughtful input.
Tom
Last April my partner and I purchased a complete"new" re-manufactured 4.3 liter Mercruiser engine to replace the toasted one in out boat....we purchased it through a Mercruiser dealer who installed it. We also had them install a full fresh water closed cooling system that was less than a year old that had been installed on the old motor shortly before it failed. A month after they completed the work we noticed coolant level was dropping in the reservoir. The engine was hard starting and steamed badly and smelled like coolant. We brought it back to the dealer and he discovered that the gasket for the blanking plate at the riser manifold had failed accounting for these problems. Since then it has failed two more times and he has tried two other sets of gaskets..He assures me the mating surface of the riser and blanking plate are flat ... and no cracks can be found on the riser (the failure is on both manifolds)...What we noticed is that after the gaskets are replaced the leaks are gone but after a period of time a couple months the leaks return. He says when he takes the risers apart the gaskets look like they are deteriorating. He uses a mercruiser coolant that is reddish in color. Now he thinks maybe this coolant is attacking the gaskets and causing their premature failure.
I was wondering if anyone else has experienced this issue or has some ideas on what else might be going on. I am a mechanic by trade and trust the guy doing the work he is a long time mercruiser dealer/owner and highly rated. At this point he is thinking we should try replacing the gaskets again (he has tried several different manufacturers) but he thinks we should try the green automotive coolant instead.
Thanks ahead of time for your thoughtful input.
Tom
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