Mercury 210hp function checks

[Twtherrien]

Hello All,
My friend and I have been talking. He just bought a boat that needs some work on the power head. We are exploring our options on rebuild, but our other concerns are preventing it from happening again. Especially on my boat which has the exact engine. I’m wondering if there are any good posts on preventative maintenance checks to prevent blowing a cylinder. Ex. Testing the over heat buzzer, checking oil pump function, etc. my other friends are always talking about losing the oil pump and blowing the engine. Are there any PM tasks/ function checks or warning signs to ensure that this doesn’t happen. Or it’s a don’t notice until it’s too late type thing. I’m debating spending the $200 and getting the smart craft SC1000 to hopefully get a little better information. I’ve had the boat out about 12 times so far, but I really want to ensure this doesn’t happen. Any advice or other forums you could reference would be helpful. Also nobody around us want to work on them.

 

[Dr Honda]

The smartcraft gauge won't really tell you anything, since you have a 210 engine. Actually... I don't know if it will even talk to it's ECU. Even the gen1 EFI engines are minimal.

You have a 17'ish year old 2-stroke, and unfortunately... it's at the end of it's life. If it was mine... I would pull the power head this winter, and do a "Refresh" on it. If you do... it will last another 17 years. If they cyl's are in spec... it will be under $1k to do it properly.

With that said... a monitor of the cyl pressure is your best bet. The issue is... when the rings and cyl wear... you start to leak hot combustion gasses back past the rings. First... this makes the piston skirt hot, and leads to melting. Second... it burns/displaces the oil and scars the pistons. Third... it gets carbon down in the rings, and sticks them, in turn... amplifying the other 2 issues.

So... I know I see people say all the time... "As long as they are all close together, you are OK". Well... that's a load of shit. There is a spec on these engines, and as it drops, it slowly eats itself. If you monitor the compression... and you notice a drop... then a rebuild can be done before a "Meltdown" happens. It's much cheaper to hone, and re-ring an engine, than to do a full rebuild. Especially if it blows apart, and kills the engine case.

As far as the oil pump... there's no good way to check it. But it's not as bad as people say. Out of all the Merc engines I've seen melted, only a few were gear related. AND... one of those had a known overheating issue. (So I can't really place blame on the oil pump gear) I've also seen 2 give up where the top oil tank was dry. The owner forgot to put the oil cap back on, and ran the engine out of oil. They blamed the "Oil Injection" but in reality... it was user error.