big block-2
Recruit
- Joined
- Jul 27, 2007
- Messages
- 2
Hello everyone.
I am the new owner of 1981 Alca, with a 140 OMC motor . I got it from a friend of mine that was moving to Florida .. Upon firing it up for the first time in two years we found out that he didn't put enough antifreeze in the motor .. Two large cracks on the side of the block ... Feeling bad about the deal he went and got a used motor from a marina ... It's a 140 Merc.
After removing the exhaust manifold I noticed that the intake and exhaust ports were smaller , not as high as the OMC ... Is this a lower HP motor than the 140 OMC since the ports are smaller ??
The number on the block next to the distributer for the Merc. is MO5170RX the date code is 1-31-90 and the casting number is 14096620
For the OMC , M12140RB ,date code 1-10-79 and the casting number 2770008
Do I need to install the head from the OMC to the merc. block ???? Are the cams the same and what about the compression ratio . I havent dissemble the motor yet ..
Thanks for the help
Hans
I am the new owner of 1981 Alca, with a 140 OMC motor . I got it from a friend of mine that was moving to Florida .. Upon firing it up for the first time in two years we found out that he didn't put enough antifreeze in the motor .. Two large cracks on the side of the block ... Feeling bad about the deal he went and got a used motor from a marina ... It's a 140 Merc.
After removing the exhaust manifold I noticed that the intake and exhaust ports were smaller , not as high as the OMC ... Is this a lower HP motor than the 140 OMC since the ports are smaller ??
The number on the block next to the distributer for the Merc. is MO5170RX the date code is 1-31-90 and the casting number is 14096620
For the OMC , M12140RB ,date code 1-10-79 and the casting number 2770008
Do I need to install the head from the OMC to the merc. block ???? Are the cams the same and what about the compression ratio . I havent dissemble the motor yet ..
Thanks for the help
Hans