I can't figure out how to drop the lower unit on a 1972 Mercury 1500(150HP) outboard. PLEASE PLEASE help!?

1)Do I have to disconnect any transmission cable or anything by the motor? If so, how?

2) How many bolts to I unscrew from the lower unit near the propeller?

3) Is there anything else that I should know?

Reason for dropping the lower unit is because I just bought this boat and I'm changing all the fluids, spark plugs, and water impeller. And by any chance you know what water impeller I need will help me too since I can't find it in the owners manual.

Thank you allI can't figure out how to drop the lower unit on a 1972 Mercury 1500(150HP) outboard. PLEASE PLEASE help!?Above post describes how to remove.

When replacing the lower, the shift shaft (Splined shaft in front of main shaft) must be put back the way it came off otherwise you can have a shift problem.

Put the throttle lever in neutral, turn the splined shaft on the lower so it is in the middle of it`s range (the prop must turn free so not in fw or rev gear) and the splines should align ok just before placing the lower back up. Dont forget the quad shaped O ring on the oil passage between the two halves!

Refill the oil from bottom up till it floods out the vent plug and use new seal washers.

FrankI can't figure out how to drop the lower unit on a 1972 Mercury 1500(150HP) outboard. PLEASE PLEASE help!?you can view your parts catalogue and engine schematic diagrams online at http://www.ishopmarine.com



the shift rod has to be disconnected. not sure where it is on that motor. on most engines of that size %26amp; vintage, it's under the bottom carburetor.



four retaining bolts, there might one more above the propeller, and there might even be one hidden under the torque tab. Score a line across it so you can get it back like it was.



put anti-sieze or similar on the retaining bolts when you reinstall, to prevent them getting froze up on there for next time. I use OMC gasket sealing compound.



put molly lube on the drive shaft splines, same reason.I can't figure out how to drop the lower unit on a 1972 Mercury 1500(150HP) outboard. PLEASE PLEASE help!?No need to panic,it's really not that hard.

1)Shift into forward gear.

2)There are 7 bolts to remove.First remove your trim tab.

There is a plug on the top of the drive unit and when you pop it out,down inside there is either a 5/16 or 3/8 Allen head bolt.

3)After you have removed it look up under the trim tab and you will see another Allen bolt.Remove it next.

4)On the underside just back a little from the last bolt there are 2 5/8 nuts to remove.

5)At the rear you will see two more 5/8 nuts to remove.After removing these there is one more back a little farther just up a little.Once you have removed the last nut it is ready to come off.It may be stuck on a little,so the easiest way to make it drop is to use a screw driver and pry down on the 2 nuts on the rear as you will have noticed that they would not come off all the way yet.The part number for your Impeller is 47-89984.

Hope this helps.