Replacment motor choice?

[johcar2]

I have a 1984 Mercruiser 3.0, 140 hp, that I think will be cheaper to replace than repair. What engine, with more horsepower, is the better fit for the 3.0? Replacement of drive could be included in this change as it looks pretty worn.

Thanks
John

 

[dollarten]

Re: Replacment motor choice?

You are pretty well stuck with the 4 cylinder set up . Nothing wrong with this engine setup . They are light , fairly quick and good on gas . If you were to upgrade to a v6 power unit , you may as well as look for a dfferent boat and stay away from the 470 . they have a different bellhousing bolt pattern

 

[greg82255]

Re: Replacment motor choice?

Switching to a v6 or bigger motor would involve some glassing of new motor mounts. When you say cheaper to repair than replace, what do you mean? What's wrong? You may be able to buy a rebuilt long block and swap over your parts.

 

[DarrinT]

Re: Replacment motor choice?

Looking for a motor and outdrive could be the expensive way

Cracked the head on my 1973 Starcraft Islander Mercruiser 140 (3L)

bought a 1971 Larson for $750 that had bad osmosis in the hull and stripped it and junked the hull

I got:

-a motor that was professionally rebuilt in the late 80's with only 450 hrs on it

-an outdrive that had an all new top end but a bad clutch dog in the lower end

- 2 or 3 thousand dollars worth of spare parts

Having two of everything is very handy when my starter went last week and I had another one sitting on my bench ready to go

 

[04fxdwgi]

Re: Replacment motor choice?

I have a 1984 Mercruiser 3.0, 140 hp, that I think will be cheaper to replace than repair. What engine, with more horsepower, is the better fit for the 3.0? Replacement of drive could be included in this change as it looks pretty worn.

Thanks
John

I don't know how handy you are, but I rebuilt the '78 140 I had back in the early 90's and that little motor was a screamer and was stingy on the fuel. Wish I still had it, as it gave me zero problems after the rebuild. That little bad boy is basically 1/2 of a 327 motor.

 

[04fxdwgi]

Re: Replacment motor choice?

Looking for a motor and outdrive could be the expensive way

Cracked the head on my 1973 Starcraft Islander Mercruiser 140 (3L)

bought a 1971 Larson for $750 that had bad osmosis in the hull and stripped it and junked the hull

I got:

-a motor that was professionally rebuilt in the late 80's with only 450 hrs on it

-an outdrive that had an all new top end but a bad clutch dog in the lower end

- 2 or 3 thousand dollars worth of spare parts

Having two of everything is very handy when my starter went last week and I had another one sitting on my bench ready to go

If you have a spare of anything, the origional will last forever. It's the part you don't have that is the one to break.

 

[cpt ron jc]

Re: Replacment motor choice?

well no matter its not cheap,i replaced my 4.3 with a motor from rapido,everything on my old block was so worn that i replaced many new parts for new block,check around for a good used drop in,although now my engine is gleaming with look and power,rapido makes a great long block money wise a drop in would have been close to what it cost,i have seen good lowcost low hrs drop in motors on e bay.