I had an elbow failure last trip where a hole blew through the outside bottom wall of the elbow between the manifold and the exhaust pipe blowing fumes and a tiny bit of water all over. After pulling the elbow it's completely rotten through and through with plugged holes and collapsed walls between chambers. I pulled the manifold and can't see any signs of water intrusion or corrosion around the exhaust valves, the spark plugs are all dry and brownish and engine oil looks perfectly normal. I looked down the spark plug holes as best I could with a flash light and the tops of the pistons are pretty black, not a lot of shiney metal in there. I did a compression check several months ago and found startlingly low compression all around 100, but brushed it off because the engine runs too stong and the tester was a cheap harbor freight jobber. Any recommendations from this point?? Unfortunately I don't know much of the history, I bought the boat about a year ago and the hours meter shows 550 right now.
Also I found 2 different elbows for my manifold, 76325 and 76351, the one I'm replacing is 76325. I tried to find discussions on the difference between the 2 of these and came up dry, but I went ahead and bought the higher number one and the 2 are a lot different. 76325 is flatter and wider and 76351 is tall and narrow. 76351 is MUCH heavier duty, about 7 lbs heavier and thicker walls. The area that blew out the wall on my old one is sloping cast iron up to almost an inch thick, the same thing will not happen, although I know the outside wall was the least of my worries when the water chamber walls inside were also rotted away. Does anyone have any more info on the these 2 elbows?
Thank you.
Also I found 2 different elbows for my manifold, 76325 and 76351, the one I'm replacing is 76325. I tried to find discussions on the difference between the 2 of these and came up dry, but I went ahead and bought the higher number one and the 2 are a lot different. 76325 is flatter and wider and 76351 is tall and narrow. 76351 is MUCH heavier duty, about 7 lbs heavier and thicker walls. The area that blew out the wall on my old one is sloping cast iron up to almost an inch thick, the same thing will not happen, although I know the outside wall was the least of my worries when the water chamber walls inside were also rotted away. Does anyone have any more info on the these 2 elbows?
Thank you.
