Mercruiser 120/140

[cpdad93]

I have an 87 Larsen 120 mercruiser ( the wife’s fishing boat). The 120 is froze up. Is the 140 a direct swap as I did find one of those. A mechanic told me even other 2.5s may not be a direct swap as there are multiple bolt patterns on the 2.5. TIA, Don

 

[Scott Danforth]

your mechanic is an idiot. there is the 1990 and older with the 153 tooth flywheel and the 1991 and later with the 168 tooth flywheel. the mounting patterns on the flywheel housing is the same for all years which is the SBC bolt pattern.

 

[Bondo]

I have an 87 Larsen 120 mercruiser ( the wife’s fishing boat). The 120 is froze up. Is the 140 a direct swap as I did find one of those. A mechanic told me even other 2.5s may not be a direct swap as there are multiple bolt patterns on the 2.5. TIA, Don

Ayuh,...... Welcome Aboard,...... If yer talking about I/O motors, Scott has you covered, 'n yes, the 140 is a direct swap,.....

If yer mechanic is talking about automotive motors,... He's right,.....
The automotive 2.5l motors are from a Pontiac design, not the Chevy design used in boats,....

 

[matt167]

Well, if you go too old, risers are different but you can swap any 2.5 or 3.0L without much issue. 1990 thereafter needs a different coupler but it’ll also work