Motor mount dimensions

[Arrowglassrestorer]

I have a 77 arrowglass with a 1977 3.0 mercrusier in it. I am taking out the entire unit and replacing it with a completely rebuilt 1988 3.0 mercuser alpha 1. The new rebuilt apha 1 will include motor , transom plate, bell and outdrive. Will I have to change my current transom cut out or the front motor mount location.

 

[Bondo]

Ayuh,.... I believe the '77 is the later bolt pattern, 'n if so, the most ya might have to do is tune the keyhole abit,... or not,....

If the '77 is the earlier bolt pattern, a couple of the holes will need to be redrilled slightly wider overall,...

 

[Arrowglassrestorer]

how about the front motor mount. Is it the Alpha 1 same distance from the transom as the old one?

 

[Bondo]

Ayuh,... Should be, But,... Test to verify,....

 

[achris]

Front mount is a direct bolt in. 77 was around the year of the change. If the old gimbal housing had hinge pin mounted trim senders, you'll bolt straight in. If it had the senders not on the hinge pins, yeah, like Bondo said, couple of holes move, and the cutout widens slightly in the middle.

Chris......

 

[Arrowglassrestorer]

Thanks great it does not sound like I will need to fill any of the transom. But I do wonder about the location of the front motor mount in relation to the transom. I have measured both and the alpha 1 semi to be a inch or two longer . Does anyone have any experience with this. The old engine ser. # 4514691

 

[achris]

... . Does anyone have any experience with this. The old engine ser. # 4514691

Yep. Used to do repowers from the old 120hp/140hp engines to the 3.0 Alpha One Gen IIs. Front engine mount bolts straight into the old holes.

The engine, from front to the back of the flywheel housing is slightly different, but the inner transom plate is also different, coincidentally by the same amount.

Chris.....