Need help to R&R lower unit on 1987 Johnson 150GT and swapping shafts

[JaxLen3]

Hello,
Thanks for the opportunity to post a question here, and thanks again for taking the time to read the post and ultimately help me out.

I was on the way to Rodman to do some bass fishing, and the road to the Kennedy ramp is treacherous at the very least. When I got there and trimmed the motor up, to remove the motor toter, the lower unit was bleeding a trail of oil from a small crack!

I checked around for a used lower unit, and found two that are very affordable. Mine is a short shaft 20"... One of the used units is 20" from an 87 150GT like mine, and the other is long shaft 25" from an "80s" 175... I may buy them both because I don't want to be stuck looking for another unit in the future, and also because I can hardly pass up a spare complete unit for $100 (both are $100ea). Unfortunately, the one nearest to my location is the 25" shaft and the exact fit is about 3 hours away..
Here's my dilemma... I have to remove the unit on my engine and install the one I purchase. Not such a big deal for you perhaps, but I have never done this before.
May you please tell me where there may be a video that demonstrates this process, or would you be willing to guide me on here how to do it?
1) How do I remove mine? I have to know this no matter what I choose in the following questions...
2) How do I swap out the shafts if I get the 25?
3) Is it easy enough for a mechanically inclined individual who's never done it, to swap out the shafts?
4) Would I be better off not even fooling around with the long shaft, and just go for the 1987 Short shaft that fits my boat as is?

Thanks in advance for your help, advice, and patience with a rookie...and thanks again for allowing me to post this.

Grace to you, Len

[pauldavid]

im sure there are videos on you tube that will guide you to removal of your lowerunit, in swapping the shafts from a 25 to 20 , well it requires some special tools and is alot more to the story than just swappin out shafts, gears and shims in there and all that has to come out to swap the shafts. have you thought of finding a reputable welding shop that welds aluminum and have crack welded up on your old unit, may even be able to do it on the motor without removing the lower, my buddy has his welded on his mercury several months back without any problems.

[gearcaseman]

Motor toters are notorious for doing this. Now, even though the price of the used cases is spectacular, you don't know what's inside unless you go in and examine, so be careful here. Fixing the crack is an option, I personally use a cold weld compound that works really well in this area of the case without distorting the aluminum from heat. Switching out the shafts is not that big of a deal, but removing the carrier from this old a motor can be. Then you have the chore of removing the snap rings inside which can be tedious. Removing your case is fairly easy. The tricky part is removing the shift rod pin, as this takes patience, but you can do it. That pin removed and 6 bolts out and the case comes down.

[JaxLen3]

I've been unsuccessful at finding any video to remove it, so I was wondering if you could tell me how the shift shaft is removed on this thing?? How do I remove the pin as you put it? I see the head of a bolt there, but not sure if that's what I need to turn off.

[gearcaseman]

O.K. Put the control box in reverse. Find the 3/8" bolt head going thru the shift rod working from the left side of the motor. I like to use 1/4" drive sockets for clearance. Snake your way with universal joints to the bolt and remove it. You may want to move the V.R.O. out of the way for access. Remove 6 bolts holding the case to the mid section (2 above the prop and 4 on either side of the case) Tilt the motor @ 30-45 degrees for driveshaft clearance and wiggle the case down. Installation is a reversal. But watch carefully that the copper tube hanging down from the motor gets inserted into the water pump correctly as you're going up with the case. Set the shift rod height at 22 1/16" measured from the mounting surface of the case to the center of the hole while in neutral and you should be good to go.

[ChampioNman]

Here you go, was stickied right under your nose. JohnRudeTips

[tdt91]

I found that removing the port side cowling pan it's much easier to get the shift rod in and tightened down. should be about 4 bolts to remove pan. good luck

[ChampioNman]

I found that removing the port side cowling pan it's much easier to get the shift rod in and tightened down. should be about 4 bolts to remove pan. good luck

Can't do that on a cross flow like his, it is a one piece belly pan. Easiest way is to remove the VRO like Eddie said. A flex driver works wonders.

[JaxLen3]

Thanks for the help guys. I was able to do the job. However, I have another problem. The LU I replaced my old one with is doing something I have never seen before in my life!
I have Oil coming out of the weep hole!

I searched for something on this and found this thread here on the BBC - Please check it out and if you can help us out (me and the original poster) I'd be extremely grateful.

http://www.bbcboards.net/evinrude-jo...hole-foot.html

[gearcaseman]

More than likely you have a bad seal at the driveshaft bearing carrier located right underneath the water pump. But to be sure, do a pressure and vacuum test to know for sure.

[JaxLen3]

Thanks Gman. Ive seen some info about pressure tests but nothing about vacuum testing. How do I do a vacuum test or would either test produce the proper results?

[ChampioNman]

You will need a tool like a Mighty Vacuum tool, you can get one at Harbor Freight.

[gearcaseman]

Thanks Gman. Ive seen some info about pressure tests but nothing about vacuum testing. How do I do a vacuum test or would either test produce the proper results?

The vacuum test will check the outer seals on the propshaft and the driveshaft. The pressure test won't check these two seals.