help installing lower unit

[paul0203]

Hello. I'm a newbie to boating. I have a 1980 Wellcraft with a Mercruiser 470 with a pre alpha stern drive. I removed the lower unit to replace the water pump. I'm having trouble reinstalling the lower unit. I can't get it to slide all the way back up. From other things I've seen the drive should have been in gear before I removed the lower unit. I did not know this before hand if this is true. Please help!

 

[H20Rat]

It absolutely has to be in gear (forwards) to get it back on. There is a little arm on the drive that engages with the transom part, and the pieces all point straight forwards when in gear. It is possible you bent/broke one of the pieces by removing it in gear.

Above all else, never force it back on! If it isn't going on easily, something isn't lined up.

 

[tschmidty]

So you are talking about mating the upper and lower on the drive, it's a bit tricky since you have to line up the water tube, the drive shaft and the shifter.

It sounds like you just dropped the lower with the upper still connected to the boat?

 

[wellcraft-classic210]

Yes -- If its just the lower section that was pulled its going to be tricky to realign --

If this is the case you will need to

--align the splines on the drive & shift shafts & water pump tube
--Take care not to damage the shaft seals -- they can be pushed up & cause a leak ( pressure test after assembly will tell )


I have always pulled the whole drive & believe that's the recommended procedure -- The experts here may have some better insight on the easiest path forward.


It may be best ( lower risk & easier ) to pull the top 1/2 off & reassemble on a bench

( Pulling the top 1/2 requires the shifter to be in forward for the shift shaft to separate without damage )

 

[stonyloam]

Yeah, pull the upper and check the alignment, gimbal bearing and lube the u-joints. Reassemble on the bench. Shift the contro handle to forward, turn the lower shift shaft all the way clockwise and rotate the prop counterclockwise until it locks and use a bungee to keep it locked. You will need a gasket set. Should go back together.

 

[paul0203]

Hello all,

Thanks for all the advice. I did take the lower unit off and not the upper. It wasnt in gear when I took it off. Sounds like I need to take the upper off to get it in. How hard is this for a newbie? Anyone have any vids or step by step instructions Thanks everyone?

 

[paul0203]

How do I pressure test after I get it back together?

 

[Bt Doctur]

Dosent matter to remove a upper by itself but its best to shift into fwd gear, remove the rams, remove the 6 nuts and pull rearward

 

[paul0203]

Hey bt doctur what are the rams

 

[Bt Doctur]

the hyd cylinders that make it go up and down, attached to the upper unit

 

[stonyloam]

Do a search for “installing Mercruiser Outdrive” and look at Chris’s videos on instillation and alignment.

 

[paul0203]

Thanks for all the help!