Yanmar 3GM30F - reliable?

[Jhull]

I just found what seems to be a decent deal on a 3gm30f, $3,250.00. The add says low hours, 2.61:1 gears, mounts, panel, exchanger cooled, S/N 08634.
Does anyone have a strong opinion on these?
It's for a thirty foot C&C. I realize it may be a little over horsed. I'd like to hear thoughts.
Thanks,
J


Sent from my iPhone using Cruisers Sailing Forum

[Vasco]

Great little engine. I've had two. Simple to service.

[roverhi]

Have one in my boat and it's been totally reliable though don't have a lot of hours on the engine.

[Cheechako]

Not really over horsed at reasonable RPM. You might ask why he's getting rid of it. they do have some issues occasionally but many engines do.
Some early mid 90's engines have had piston problems... hard to know if more than other engines. They run nice though.... and smoother than small ones!

[gamayun]

What year? Is it a new engine or rebuilt with low hours? I understand that these engines need to be worked so if it has sat around for a long time, there might be internal corrosion. Might be some things to look into or get a lab test done.

I didn't have a clue about these engines when I got mine, but I knew Yanmars' reputation. I'm sure I still only know just 15% of what needs to be learned about them, but that's probably plenty good for about 80% of what might ail ya. Mine has at least 2600 hours (hour meter wiring went bad and haven't replaced). I'm assuming 10,000 hours is not unreasonable, if treated (i.e., run) well and not overheated.

[FSMike]

We've got two in our cat, over 3,000 hours on each, great little engines (knock on wood lol).

[Jhull]

Darn thing sold before I got a call in!!!

Thanks for the replies, everyone!

J


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[Cadence]

Originally Posted by Jhull

I just found what seems to be a decent deal on a 3gm30f, $3,250.00. The add says low hours, 2.61:1 gears, mounts, panel, exchanger cooled, S/N 08634.
Does anyone have a strong opinion on these?
It's for a thirty foot C&C. I realize it may be a little over horsed. I'd like to hear thoughts.
Thanks,
J


Sent from my iPhone using Cruisers Sailing Forum

You can't by a small OB for that. I'd look at it and if a rod isn't coming out of the block, I'd take a chance on what is touted to be reliable. JMHO and not my $. Don't know I would on blind faith if I couldn't at least turn it over by hand myself.

[ex-12m-guy]

The Yanmar GM series are generally well built and reliable engines.
Replacement parts cost is also reasonable.

However, where did this engine come from? Is it a "pull-out?" If so, what
was it pulled from, and why? How many hours on the Hobbs?

I suggest never purchasing an engine unless you can see (and hear) it run.
The engine in question can be set up on short railroad tie sleepers, plumbed to clean fuel and a large bucket of water, wired to a battery, and fired up. It should start immediately (after priming) and run without producing either white or blue smoke.

Check the oil pressure with a real gauge. It should be 45 lbs. minimum.
Does the alternator charge the battery? Alternators are expensive to replace.

Hold a 2' piece of broomstick to your ear and press the other end to the block and crankcase. You should hear the ignition "knock" in a regular rhythm. However, any other knocking noises out of the ignition rhythm pattern can indicate problems with the lower end, usually not worth fixing in an engine of this age.

Wipe the engine clean before running, and check it all over for leaks after shutdown.

There is no reliable way to check the transmission out of a boat. I would hold back at least $1,000 from the seller (via a third party) as a guaranty
that the transmission is OK.

The price seems high. The local Yanmar dealer here offers zero hour rebuild models of this, or the next generation engine, for about the same price, including a 90 day warranty.

[flyingnut40]

I have a 2GM15 from a 30' Seidleman that is in beautiful shape with tranny that you could have for $2500.00
Shipping would be a bit of an issue as I am in Toronto area but otherwise a freshwater engine with low hours (was pickeled for last 8 years) and runs excellent.
PM me if interested.
Dennis

[Bryn49]

A very reliable engine, the only noticeable wear were the valve guides. had one for 14 years

[jessehunt]

I've got the same model in a Rhodes Pearson 41, and it's been bullet proof! Pushes 19,000 lbs along at 6 kts, and very economical on fuel.

[jessehunt]

One thing to check before installing the 3GM30F....There is an external oil line that originally was painted steel, which is notorious for rusting and leaking. It runs from a banjo bolt low on the left side of the block by the starter motor, runs around to a banjo bolt on the back of the block, then continues around to another banjo bolt on the right side of the block near the filter/fuel pump assembly. Check it for pitting and rust. It's much easier to replace before the engine is installed. The Yanmar replacement part is copper tubing, or it would be easy enough to make your own. Good luck with the Yanmar!