Engine conversion

Customdiver · Post by **Customdiver** » Mon Dec 29, 2008 12:19 am

I have a '72 31' that the previous owner changed the motors. one is a chevy and the other is a Ford. I have a couple of questions. 1. what would be the most reasonable Diesel motor to exchange it with and can I run one motor and two shafts? Your help would be greatly appreciated..

prowlersfish · Post by **prowlersfish** » Mon Dec 29, 2008 6:54 am

Do to space your limited on engine choices Yanmar is one cummins 4BTA 3.9 is a nother, Peninsular has a 6.5 diesel based on 6.5 g.m that may work .stryr is another choice . you realy only have room for 4 cly diesels due to lenth other the 6.5 thats a V8 . you don't have room for a 6 cly in line Engine . Now I am talking twin engines as far as useing one Engine with 2 shafts yes it can be done I forget the company that made that set up ,But it takes up a lot of room . alot more then what you have .

As far as runing 1 ford and 1 chevy I do not think its a big deal . I know a F30 that ran a chrysler 318 and a chevy 350 for years . also know a F36 that had 440 chryslers and when one went bad it 1 was replaced with a 460 ford as chrysler stoped making the marine 440 and begain useing the ford engine .

Customdiver · Post by **Customdiver** » Wed Dec 31, 2008 1:01 pm

Thanks for all the information...

I think I will have my engines rebuilt and stay with the gas.

RWS · Post by **RWS** » Thu Jan 01, 2009 8:53 am

if you are going to make the investment of rebuilds, now would be a good time to replace one of those so you have a pair of twins.

These engines have different torque curves and power characteristics.

This could be a real issue for resale both for resale price and the buyers who would reject the boat based on the two different engines.

The cost of a complete takeout core to rebuild should not be a big factor in the total rebuild cost.

RWS

prowlersfish · Post by **prowlersfish** » Thu Jan 01, 2009 10:44 am

I agree with RWS if your going to be rebulding anyway . but if they run fine then I would leave it alone.

Customdiver · Post by **Customdiver** » Fri Jan 02, 2009 2:26 pm

Thanks for the advise.
The Chevy motor needs to be rebuilt. So I agree that I will replace it to match the other motor.

I am also going to convert it over to fresh water cooled as it isn't right now. My mechanic says he has all the needed parts.