Will a 2GM Yanmar work?

[ggrizzard]

I have the opportunity to purchase one of two used Yanmar 2GM- F engines to repower my 1979 H30. I planned on having the local Yanmar dealer give me the answers to the following questions, but their scheduling is a problem, so I'm looking for your collective knowledge.

First question set: Anyone have experience with this repower? Will a shaft mod work or is a new one required? Is the vertical room sufficient or will the bed have to be cut down a bunch for clearance and/or for shaft alignment? Are parts still readily available for this engine? Are there any known gremlins?

Second set: One engine is rebuilt and priced at $2500 with a warranty, but a long way away from here. The second is $4000 from a local owner, as is and no warranty, although he will allow a mechanic to evaluate it. I think the first is a great deal, but if a problem develops I can't get him to fix it. The second seems high in price and the mech isn't going to warranty the unit either.

The cost of picking up the first is $100. Picking up the second is $50.

Thanks, as always, for your responses.

 

[sailaway78]

Whats in it now

It's impossible to even have an idea concerning mounts and shaft and alignment and all that on a repower, without knowing what you are replacing. As far as the choice of engines, that one for me is a no brainer. A rebuild with a warranty for a lot less money than a used with no warranty. Go for the rebuild.

 

[Chuck Creel]

It's impossible to even have an idea concerning mounts and shaft and alignment and all that on a repower, without knowing what you are replacing. As far as the choice of engines, that one for me is a no brainer. A rebuild with a warranty for a lot less money than a used with no warranty. Go for the rebuild.

I have been having the same delima for abt a yr now and i have the ysm-12 as you probably do also.

There is a chance of shaft work and wheel but the space to instyall it is ok. Also the exhaust sytem might need work. in other words its not a unbolt and bolt in another one. My mechanic estimates aprox. 24-30 housr to install the new engine. BTW a brand new 2ym15 yanmar is $6500. verses a used 2gm for $4k.

just my 2 cents.

Chuck

 

[MrBee]

If I were picking between the two I would go for the $2500.00 motor. Even if it is to far away for the warranty to do you any good the difference in price is enough to cover a lot of work later, if it would be needed and also that money could be used for the install.
Chuck says the price of a New motor like is already in the boat is $6500. You might want to consider the cost of a used motor and add the expense of the install and hassle, you might find it better to keep the same motor and just be able to swap them.

Just some thoughts from a person that has never done a repower.

Brian

 

[Ken13559]

I would go for the $2500 engine and save the $1500 for providing "warranty" maintenance myself. You should be able to download dimensional drawings for 2GM20F. You can take measure yourself to see if the engine could possibly fit.

 

[Deadline]

To answer the question posed, yes indeed the 2GM will work on a 30-foot sailboat. 1979 suggests a little heavier boat, but these Yanmars are powerful engines.

 

[redhead78]

Hey Grizz, What are we talking around 15 HP? If you really think about this, and you probably feel the same about your boat as the rest of us , the motor is one of the sailors most ignored pieces of equipt, however when we need them there is nothing more important. Think only of the motor price,all the other stuff, shafts, props, stuffing boxes, the things you may need whether you get a new or used motor. A 16 hp beta marine new can be had for around 5-6K, with a trans, less without. A used motor is like a used car you never know. Of course if you are not planning on keeping the boat its a different deal. Thats my take anyhow, if you can somehow swing it, this is not a job you want to do over anytime soon. I am doing the same job with a 35 hp, good luck to you whatever way you choose. Red

 

[MrBee]

I have a 2gm20f in our Irwin 10/4 and and the displacement is 7000lb and I can tell you the motor is more than enough. Plenty of hp left over for rough weather.
We had some rough water coming through NY harbor against wind and waves and were VERY happy with the engines performance. Didn't skip a beat and only ran it at 75% most of the way.

Brian

 

[Ross]

What ails your present engine? Can it be rebuilt for less than 3K? If it can be rebuilt then everything will still fit.

 

[Steve Dion]

This is a common retro fit. I doubt that the shaft will work, but that is what the mechanic will let you know. You current engine has a left hand prop, so you will need a new prop. This is probably one of the most important things to get correct. Get a good prop shop to help guide you on this matter.

There are two versions of this motor, so you may want to find out which one you are getting. The original 2gm was about 13 hp and the later were 18 hp.

As far as a rebuild, you may not really know that you are getting any better engine than the used one depending on how did it. The $4k is a lot more expensive than I have seen them, they are usually $2k-3k on the used market.

 

[druid]

I replaced the Volvo MD6A in my Crown 28 with a 2GM20F (see story: http://www.bcboatnet.org/boattalk/index.php?topic=628.0 )

I could have used the same shaft but opted for a new SS. Note that the Yanmar shaft coupling is HUGE - make allowances for it! Make sure the exhaust will route properly. You will most likely need to rebuild the stringers for the engine mounts, but the old ones are probably rotten anyway if you're replacing the engine (ie the engine usually outlasts the stringers! )

Also be aware it's pretty much impossible to route the shift cable so it works properly with an Edson pedestal.

With the right prop (40% calculation, 60% voodoo) that engine will have more than enough power for your boat.

druid

 

[kloudie1]

2GM Dimensions

Hope ya can read this one, GGrizzard.. Make a cardboard box this size and ya can tell really quickly if there is a major problem.. Like Steve says, I think folks do that refit .. Best of luck with the (rebuilt) engine

 

[Nereussailor]

I've got a 2 GM in my 1983 H30 and it works good. It's a little under powered though. It would be ok if I didn't have to deal with strong currents and tides. I'd go for something with a little more power like a 20 hp Yanmar.

Dave

 

[ggrizzard]

Wow! My heads spinning... So much info, and all very much appreciated.
The YSM 12 I have is original and if it fails again (It was rebuilt by Yanmar dealer once 10 years ago) some critical parts are no longer available. The 2gms I'm looking at are 18hp and would be a significant boost in power over the the 10hp I have now.
The stringers should be fine, but they have to be cut down and reglassed for any vertical engine to fit anyway. 'O2 Addict' in Fla sent pics of his Vetus repower. Same size engine as the gm but I can't afford a $5k. engine plus install.
Druid, Your comment about the shift cable has me spooked. I would like a PM of your obsevations of the incompatability problem.
Thanks All,
G