Lower unit is shot

[rnvinc]

2 marine mechanics that I took my LU to said the unit is shot and I would be better off finding a used LU for my '93 Johnson 50hp.

So, while I've been searchin ebay, craigslist, and a local 'sell-anything-site' I thought I would try and get the unit apart myself just so I can see how the innerworkings of a LU actually works.....that's the OCD part of me...curiosity...

I'll be ordering a Seloc manual soon but I have a question that someone here may be able to answer before my manual gets here..

I've got the retaining nut off the bottom of the verticle driveshaft, the thrust washers and bearing out of the top of the housing but something is still not letting the verticle driveshaft come out of the housing..

Does the bottom bearing and pinion bearing have to come off the bottom of the driveshaft from inside the housing before the driveshaft will come out of the housing?

[2fshmore]

Have you disconnected the shift rod that comes up thru the housing from the shift lever? If not you will have to do this with the shift lever in reverse. Then you should be able to seperate the lower unit from the housing.

[2fshmore]

If you live in central Ga. would be glad to give some help. I have one apart now waiting on new bearings.

[rnvinc]

I should have explained in a little more detail..

I have the LU removed from the motor and sitting on my workbench...

I am trying to completely disassemble the LU to see how things work inside a LU....

I have the shift rod completely out of the LU.....

I have everything from the top of the LU housing removed down to the thrust washers and bearing which I also removed from the top of the LU where the verticle driveshaft enters the LU housing......

I have the propshaft carrier removed....the large outer propshaft drive gear (about 4 inches in dia.) removed.. and the retaining nut from the very bottom of the verticle driveshaft removed...

Looking inside the LU propshaft housing I can now see the large inner propshaft drive gear (about 4 inches in dia.)and the small gear on the bottom of the verticle driveshaft (about 2 inches in dia.)....

At this point neither the propshaft nor the verticle driveshaft will come out of the LU housing....

My question is...does the small gear (about 2 inches in dia.) have to come off the verticle driveshaft from inside the propshaft housing before the verticle driveshaft will come out of the LU housing?

[2fshmore]

I think i understand what you are saying. On the ones i have worked on you have 2 large snap rings inside the case have you removed these? If not you will need snap ring pliers about 12" long to reach inside the housing to remove these. After removing snap rings you can take the gears out.

[2fshmore]

Forgot to mention you will have to remove pinion nut also to get the gears out.

[rnvinc]

I have removed the pinion nut that you mention.....

My question is about the small gear (about 2 inches in dia.) that the pinion nut secures to the verticle driveshaft.....

Does this small gear come off the verticle driveshaft before the verticle driveshaft can be removed....or....does this small gear come out with the verticle driveshaft....?

[2fshmore]

Glad to help. I finally figured out what you want to know. Yes this gear does come off the shaft before you can remove the rest of the gears. I made a home-made puller to pull the driveshaft and the pinion gear will come off if not before the drive shaft starts to come out it will come off as you pull the driveshaft. You may or may not know but the drive shaft passes thru a bearing and has to be helped to come out. Sorry i dont have anyway of posting pix of my homemade puller. If i knew where you were located maybe i could help more.

[2fshmore]

You might want to try a pair of visegrip pliers. Put a rag around the shaft and then clamp pliers on the shaft and give it some strong tugs. If that doesnt do it try taking a hammer and hitting(not too hard) on the underside of the visegrips knocking up on the driveshaft. If you have anymore trouble maybe i can think of something else.

[The Marine Doctor]

Normally you can just give the shaft a rap with a dead blow and it will come out.

I have seen in the past...pinion nuts welded onto the shaft.


TMD