Lower

[Merc 2.5]

I have found a lower in the cmate I just got and has # 1647 7223 no c# nowhere. Has pin in top driveshaft

[Merc 2.5]

Did the ole inlines come with ratching lowers?

[tlwjkw]

pre-load.. no tellin' whatcha got.. not worth tha hassle my way a thinkin'...….

[Merc 2.5]

Only 2 motors it could had came from. 140 in line or 78 175. Buddy mine wanting a case with 2/1 gears , I guess if it fits on my mid I'll know. Can u explain to me difference in pre load and ratching plz?

[tlwjkw]

pre-load was all there was till sometime in tha mid ta late '80's best I remember so that's not cast in stone...… pressure on that pin from bottom of tha crank is what holds tha top bearing of tha driveshaft in place.. ratcheting cases and pre load had nothing ta do with one another.. tha ratcheting case was all of 'em till somewhere in tha mid '90's maybe.. don't remember for sure there either.. they will let tha prop "ratchet" in gear if motor quits so tha boat won't act stupid if ya travelin' at "lite speed"....

best I can do with what few faculties I've got left.. almost caught up with bobby...….

[pbxcomm]

The top pin (spring) placed a pre-determained load on the pinion (forward/reverse) gear (backlash). Without the preload pin/spring, the drive shaft would creep upward while running and increase backlash. Some motors had the top pin/spring for preload and some did not. It was required to set the backlash accordingly.

[pbxcomm]

I beleive the ratcheting you reference is the "Sliding Clutch Assembly". The Sliding Clutch "slides" alog the propshaft engaging either foward or reverse gear.