Repowering Hunter 31

Status
Not open for further replies.
J

Jon Dodge

I recently purchased a 1985 Hunter 31. It currently has a 13hp Yanmar 2GMF. The engine needs to be replaced. Is the best replacement a 2GM20F or a 3GM30F? Will the 3GM30F even fit in the engine compartment w/o modification? Thanks. -Jon
 
T

Tim Leighton

REBUILD?

Jon: Have you considered a rebuild of your current engine? I've got the same model/year and been told there are many more years/hours remaining on my engine (I admit to fairly light use and "relatively" good upkeep). Is your old 2GMF really shot? A marine diesel should last at least 10,000 hours with reasonable maintenance. A new engine will set you back close to 25-30% of your purchase price, where a rebuild would be much less costly. To answer your question directly however, I've been told the later versions of the 2GMF (18 and 20 hp) have identical mounting bolts. I doubt the 3GMF would and besides, the added HP probably wouldn't do anything but add to your fuel use and maintenance headaches. You may get a bit more power to punch through choppy seas, but won't see hardly any increase in cruising speed (hull speed is one of those dirty physical limitations we can't do anything about!). Good luck and keep us posted as to what you decide! Tim L. (S/V "TIDE") Happily "motor"sailing on the Ches Bay!
 
J

Jon Dodge

Thanks Tim

Tim, Thanks for your comments. The boat I purchased has been neglected for some time. The boat was half sunk for about 10 months and the engine has been in brackish water for this period of time. Many lower parts of the engine, including the transmission, appear to be one solid mass of rust. The good news is a repower actually will cost about 200-300% of the purchase price (I picked it up cheap and the boat still has great potential). I also feel the 2 cylinder is probably enough power in normal conditions. However, since I have to repower anyway it may not hurt to be able to feel more secure bucking the current in a headwind/sea. The two cylinder may be a better "bolt-in" installation though. Any experience with this engine swap? Thanks. -Jon
 
Status
Not open for further replies.