What is the condition of this Yanmar 3GM30F?

[MicHughV]

All that rust showing in various engine parts would be a concern to me.
How did it get there is the question foremost in my mind.
Always difficult to make a determination from just an overhead photo, but seeing it there tells me that there was water ...spray, broken hose or otherwise in there.

Would certainly give this engine a good go over as outlined above. Check all the hoses, hose clamps, wire connections, etc.

The age of the engine...20 years old......would also raise some flags. Is this engine still made, can parts be found, etc. If sitting for a long time, the water impellor may have deteriorated, broken, etc.

Certainly, check the oil, and find out when the last oil changes was and while you are at it, check all the other fluid levels, transmission, cooling, etc.

Yanmars are very good engines, but take this boat for a test spin before putting pen to a checkbook. Does the transmission shift smoothly...forward...reverse...does the engine come up to rpm underload, does it shake and shudder and so on.
Check for leaks after it's run. Monitor the engine gauges while running, oil pressure, coolant ok. Check for smoke at the exhaust as well as cooling water expulsion.
Lastly, check if the alternator still puts out a charge.

It's not a five minute job, take your time. Go over some of these items one at a time.

[skipperpete]

The Saildrive on that Yanmar is never going to shift gently into gear, it has a dog clutch with absolutely zero slip so it’s important that the idle is set correctly. Yes, parts are readily available for GM series engines but ordering even simple things like injector pipes can be tricky, 3GM owners here will immediately notice the injector orientation as different, and that’s only the most obvious of the changes.
They’re a great little engine and Yanmar made this particular version just a little better, I rebuilt one that had over 7,000 hrs on it which could have continued happily working for another few years had I reassembled it with new gaskets and a decoke. The drive plate seems to be a bit fragile, I’ve replaced quite a few that had broken springs, possibly due to that Saildrive dog clutch ..... but no catastrophic failures. The OP’s photo seems to show a new nut on the port front engine mount so it does indeed look like there’s been some work done, maybe a new engine mount but hard to see any more than the nut.

[workmaster2n]

Sorry, I missed the email notifying me of these replies!

I've asked the vendor to send me some more photos of the engine bay and engines. I'm still in the early stages of due diligence, so no pen to paper yet. From the sounds of it, there are some legitimate concerns about these engines. Even if they turn out to be in good nick, sourcing parts sounds like it could become problematic.

If I proceed further along with the deal, I'll be sure to have a diesel mechanic check out the engines, as well as do the tests once the boat is dropped back into the water.

Thanks for all the informative replies!

[Goodxcharly]

I would walk!
Did you overlook your spare anchor, saildrive. Though they are a excellent anode for your engine.
Nothing good about them. Catalina the Chevrolet dealership for sailboats does not use them.
Keep looking!
Cheers! Dave

[ccanupii]

Get a mechanical survey...

[sinnerman]

Originally Posted by ccanupii

Get a mechanical survey...

Originally Posted by ccanupii

Get a mechanical survey...

Ditto on a mechanical survey.

The missing/broken head bolt/stud is a real eye-opener / concern. I would freak out if I saw this on my boat.

The rust appears to be localized to areas that probably had some water leaks from above.

I have seen HORRIBLE engines where they were basically a solid block of rust. So by comparison, this engine does not look so bad...

Pay attention to the TRANSMISSION as well. Especially any slippage of the clutch (cone) assuming this trans has a cone...

Since this appears to have a sail drive, when is the last time the sail drive pizza plate diaphragm was replaced?

Again being a sail drive , you will need to inspect the drive for corrosion with the boat hauled out...


My two cents

cheers.

[MVDarlin]

Ask to see the vessel log book. It should have maintenance records.

[workmaster2n]

Finally got a chance to see the boat. The engines were the least of our concerns. On to the next!

[Pete7]

Originally Posted by workmaster2n

Finally got a chance to see the boat. The engines were the least of our concerns. On to the next!

Oh dear, that bad

[workmaster2n]

Originally Posted by Pete7

Oh dear, that bad

It was a beautiful boat, professionally built, and then a "handy" previous owner started making modifications. Would have cost as much as the boat to undo their work.

[5BTM]

Originally Posted by workmaster2n

It was a beautiful boat, professionally built, and then a "handy" previous owner started making modifications. Would have cost as much as the boat to undo their work.

The same story with my CS27, lucky for me it is a relatively small boat, I am handy, have all the tools and the bones were untouched.