The background: Made a really hard stop in the boat with too many people in the back which resulted in the engine starting to make a very quiet tapping noise. Over the next 15 minutes it turned into a loud clacking noise, hard to start, and really poor power from the engine. I limped it 2 miles to the shore and pulled it out. I pulled the plugs and cleared what appeared to be water from a couple cylinders, put oil in the cylinders thru the spark plug holes and changed the oil after letting it sit for a week. Local mechanic listened to it and said I spun a rod. I built a crane and pulled the motor from the boat this weekend.
I have one of the heads and intake manifold off so far. I see lots of rust/scaling in the water passage ways (pictures included) of the heads. This looks like too much for the heads to be reused, but I'd like some feedback on that. Would you clean these heads up and reuse them or replace them? I'm going to put some kerosene on the valves and see if they leak next. (Youtube said this was a good way to check your valves) Do you agree with this method?
The cylinders don't appear to have rust in them on the piston side so I think putting oil in the cylinder and doing the oil change hopefully saved them. My oil plug has a decent amount of metal shavings on it and there seems to be quite a bit of metal in the oil sitting on top of the heads, but not in the oil pan. I don't see any obvious damage on the valves or anything on the head side, so from what I can tell reading on the forums, that means my loud clacking is likely coming from the piston rod side and I need to open it up and look at it. So my next step is to remove the flywheel so I can put it on an engine stand instead of blocks, flip it over, and look at the main and rod bearings and see the rest of the cylinder to check for any gouging, dents, or damage on anything. Am I on the right track here? There is no more assessment I can do from the top side right?
I'm mostly trying to get a pulse and any advice for if I'm heading the right direction to find my problem and then make an assessment if I can rebuild or if I need to replace.
Thanks!
1989 Maxum 2300 SC, I/O
Engine: 7.4L Bravo, 454 CID, 330HP, Ser# C662618
Outdrive: Mercruiser Bravo, Ser# 0C793737
I have one of the heads and intake manifold off so far. I see lots of rust/scaling in the water passage ways (pictures included) of the heads. This looks like too much for the heads to be reused, but I'd like some feedback on that. Would you clean these heads up and reuse them or replace them? I'm going to put some kerosene on the valves and see if they leak next. (Youtube said this was a good way to check your valves) Do you agree with this method?
The cylinders don't appear to have rust in them on the piston side so I think putting oil in the cylinder and doing the oil change hopefully saved them. My oil plug has a decent amount of metal shavings on it and there seems to be quite a bit of metal in the oil sitting on top of the heads, but not in the oil pan. I don't see any obvious damage on the valves or anything on the head side, so from what I can tell reading on the forums, that means my loud clacking is likely coming from the piston rod side and I need to open it up and look at it. So my next step is to remove the flywheel so I can put it on an engine stand instead of blocks, flip it over, and look at the main and rod bearings and see the rest of the cylinder to check for any gouging, dents, or damage on anything. Am I on the right track here? There is no more assessment I can do from the top side right?
I'm mostly trying to get a pulse and any advice for if I'm heading the right direction to find my problem and then make an assessment if I can rebuild or if I need to replace.
Thanks!
1989 Maxum 2300 SC, I/O
Engine: 7.4L Bravo, 454 CID, 330HP, Ser# C662618
Outdrive: Mercruiser Bravo, Ser# 0C793737
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