reinstalling Merc Lower unit

[CheapboatKev]

Hopefully my last issue on this impeller change today..
I'm gonna scare away the trick or treaters with my cussing..

I change the impeller (thanks guys) today on my 120hp Merc'd OD today.

Have it all back together, have the lower unit in position, but am stopping about 1/2 inch to being fully up on the upper unit. Looks like everything is where it should be...

It is in gear..prop locks turning counter clockwise...

I think it would have been a lot easier just yanking the whole leg, tell ya the truth...

 

[Don S]

Re: reinstalling Merc Lower unit

When you drop the lower unit only, the shift shaft in the upper will drop down and can turn and not line up properly. Make sure the shift shaft in the upper and the one in the bellhousing are also lined up.

You did get the quad ring on the oil passage between the upper and lower didn't you ???????

 

[ziggy]

Re: reinstalling Merc Lower unit

ive used rubber bands strategically placed to hold that shift shaft in the upper in place. after it's going together, i just break the rubber bands off...
yes, it's much much easier on the bench... i've done it both ways... now that i'm hip to on the bench. i don't think i'll be doing it the other way (with the upper still on the boat) as much...

 

[CheapboatKev]

Re: reinstalling Merc Lower unit

Don S..
Yep I got those..

Thanks both of you on the answers..
I'll try again tomorrow morning and see what happens..Doing this solo is a !!!!

If nothing else I guess I'll pull the upper and do it off the boat...

 

[ziggy]

Re: reinstalling Merc Lower unit

Doing this solo is a !!!!

, wow man, that i've never done. that sounds impossible.... hope ya find some help or get it on the bench... have ya gone and felt out yer gimble brg. yet or greased yer coupler and ujoints or inspected your bellows or run an alinement bar on it? if not, might take the upper off and do that pm + have a easy time on the bench with putting the two halves back together.

 

[JustJason]

Re: reinstalling Merc Lower unit

You know what really stinks doing solo... try doing an ocean pro 225 XL shaft or a yamaha saltwater series 250 XL long shaft by yourself. THOSE really stink.

 

[Don S]

Re: reinstalling Merc Lower unit

You know what really stinks doing solo... try doing an ocean pro 225 XL shaft or a yamaha saltwater series 250 XL long shaft by yourself. THOSE really stink.

I can agree with that, about anything that says XL on it is a Pain in the behind. Makes the Alpha look like childs play.

 

[CheapboatKev]

Re: reinstalling Merc Lower unit

, wow man, that i've never done. that sounds impossible.... hope ya find some help or get it on the bench... have ya gone and felt out yer gimble brg. yet or greased yer coupler and ujoints or inspected your bellows or run an alinement bar on it? if not, might take the upper off and do that pm + have a easy time on the bench with putting the two halves back together.

That was going to be another project in a few weeks...I really didnt want to yank the upper without the alignment bar handy...

 

[ziggy]

Re: reinstalling Merc Lower unit

I really didnt want to yank the upper without the alignment bar handy...

i hear ya man. i procrastinated too about getting one. don't bother procrastinating. just get it. you know ya gotta have one... break down and do the deed.... you won't be sorry ya did... you'll be happier...

 

[CheapboatKev]

Re: reinstalling Merc Lower unit

So I went ahead and removed the upper...

STILL not fitting on completly...I think it may be the water tube thats not aligned..But if all the bolts line up...

For once I am hating this 90 degree weather..

 

[Fishermark]

Re: reinstalling Merc Lower unit

I suspect you are right about the water tube getting in a bind. Several things have to come together all at the same time. The important thing is to not force it. You may need to physically turn the prop a little for it to line up and go together as well.

I also cannot help but wonder if you simply mis-spoke when you replied about the quad ring...

Don S..
Yep I got those..

Just to be clear - there is only one quad ring. "IT" -not "THOSE." Just making sure you are talking about the same thing.

 

[FreeBeeTony]

Re: reinstalling Merc Lower unit

Could it be the pre-load pin on the driveshaft?

 

[Fishermark]

Re: reinstalling Merc Lower unit

Tony brings up a good point - it could be that simple.

 

[CheapboatKev]

Re: reinstalling Merc Lower unit

not to sound like a moron...

But you expand on the pre load pin issue?

 

[FreeBeeTony]

Re: reinstalling Merc Lower unit

It's the pin on top of the driveshaft of the lower unt.
It's spring loaded, you should be able to push it in with your thumb.....if you can, I would put it together like you had before (w/ the 1/2" gap) and try turning the upper driveshaft (clockwise) just a bit to see if maybe the upper gear is not lined up with the lower driveshaft....if you feel it is aligned try pushing down on thte upper to see if it's just the pre-load pin holding it up.

Hope this helps......

 

[Fishermark]

Re: reinstalling Merc Lower unit

It's spring loaded, you should be able to push it in with your thumb.....

Actually, any of the ones I have seen are way too tight to push with your thumb. You can tap it with a mallet and it will depress and spring back... but I don't believe you can simply push it with your thumb. It keeps a preload on the bearings as I understand it... but I could be wrong about that. Not all drives will have the preload pin - but I think most of the older ones do.

 

[CheapboatKev]

Re: reinstalling Merc Lower unit

Mine being 40 plus years old..It definitly has that pin.
I'll give that a look as well..

Thanks

 

[wvmedic]

Re: reinstalling Merc Lower unit

Kevin they are correct on the pre-load pin, I agree with Fishermark though I haven't been able to push one in with my thumb.

That being said when you get it in place put a couple bolts in it, try turning the upper shaft like FreeBeeTony said. If they are aligned and you are sure the water tube and shift rod are in place, put you're bolts in and tighten them up. Just make sure when you are wrenching on them that there isn't to much resistance, it should go to gather easy with minimal effort.

Give me a call if you have any questions.

Jeff

 

[FreeBeeTony]

Re: reinstalling Merc Lower unit

OK........so maybe you can't push it down with your thumb.......but it should go down.........

 

[dubs283]

Re: reinstalling Merc Lower unit

just pull the upper

inspect u-joints, bellows, gimbal bearing, and if you have to, borrow an alignment bar. i',m sure if you lug your boat to a service shop they will put the bar in and check it for free

replacing a water pump and base assembly is a perfect excuse to pull your drive and take care of some NECESSARY maintenance

re-install the upper and lower halves and pressure test the drive, grease the heck out of everything and install the drive