Join Date: Dec 2011
Posts: 62
vCash: 500
Default Mercruiser Manifold Question
Ok folks, need some assistance from the pros.
Making a long story short, think I sucked up some sand/mud while on vacation and boat started overheating, gauge got to about 180 Deg and alarm was blaring. Changed impeller and thermostat and boat ran fine for rest of trip at about 150 Deg. Actually changed thermostat twice, once to a new 160 which is what was originally in the boat. Still ran a little hot with the 160 so parts house recommended going to a 140 stat. Left it like that for the remainder of the trip. I still think something is not right because it still got a little hot with the 160 which it did not do before the sand incident.
That brings me to today, I pulled the plugs on the exhaust manifolds to check for sand there. When I pulled the plugs, I found what I thought was a large amount of debris, so I pulled the elbows, risers and manifolds. I flushed everything with the garden hose and got some sand and a little scale from the manifolds. It was not enough to cause a restriction I think. However, the starboard manifold has a chunk of metal caught near one of the drain plugs. I can grab it and wiggle it with needle nose pliers, but it will not come out. See pic below, it is the pointed piece of metal in the drain hole.
I am not sure what this is or how it got there. Curious if anyone has seen this before and if I should be concerned. The manifolds appear in very good shape with just some surface rust in the parts of the water jacket I can see. Would you all worry about this, or just bolt it back on and let it ride. I may see if I can get to it with my Dremel and remove enough material to get it out.
I am going to attempt to back flush the block and heads before installing the manifolds. I was thinking of getting some fittings and connecting to the block drains on both sides, remove the circulating pump and flush out that way.
A little history / info on the boat. It is a 2007 Crownline 180 BR with the 4.3L 190hp V6. It was 5 years old when I got it and had 60 freshwater hours. I was told it had never been in salt, but do not know for sure since it was used. Since I have owned it, it has only been in fresh. It now had 140 hours. The manifolds are the newer dry joint type.
Engine purrs like a kitten, just want to be sure the cooling system is right.
Any info would be appreciated.
Ron
Posts: 62
vCash: 500
Default Mercruiser Manifold Question
Ok folks, need some assistance from the pros.
Making a long story short, think I sucked up some sand/mud while on vacation and boat started overheating, gauge got to about 180 Deg and alarm was blaring. Changed impeller and thermostat and boat ran fine for rest of trip at about 150 Deg. Actually changed thermostat twice, once to a new 160 which is what was originally in the boat. Still ran a little hot with the 160 so parts house recommended going to a 140 stat. Left it like that for the remainder of the trip. I still think something is not right because it still got a little hot with the 160 which it did not do before the sand incident.
That brings me to today, I pulled the plugs on the exhaust manifolds to check for sand there. When I pulled the plugs, I found what I thought was a large amount of debris, so I pulled the elbows, risers and manifolds. I flushed everything with the garden hose and got some sand and a little scale from the manifolds. It was not enough to cause a restriction I think. However, the starboard manifold has a chunk of metal caught near one of the drain plugs. I can grab it and wiggle it with needle nose pliers, but it will not come out. See pic below, it is the pointed piece of metal in the drain hole.
I am not sure what this is or how it got there. Curious if anyone has seen this before and if I should be concerned. The manifolds appear in very good shape with just some surface rust in the parts of the water jacket I can see. Would you all worry about this, or just bolt it back on and let it ride. I may see if I can get to it with my Dremel and remove enough material to get it out.
I am going to attempt to back flush the block and heads before installing the manifolds. I was thinking of getting some fittings and connecting to the block drains on both sides, remove the circulating pump and flush out that way.
A little history / info on the boat. It is a 2007 Crownline 180 BR with the 4.3L 190hp V6. It was 5 years old when I got it and had 60 freshwater hours. I was told it had never been in salt, but do not know for sure since it was used. Since I have owned it, it has only been in fresh. It now had 140 hours. The manifolds are the newer dry joint type.
Engine purrs like a kitten, just want to be sure the cooling system is right.
Any info would be appreciated.
Ron
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