Gearcase Reseal

**25two.stroke** · 05-10-2021, 01:25 PM

1996 150 carb motor. Drained the gear oil and it was about half water. Took the case off the motor and found some oil droplets under the impeller so I figured the wp base seal had failed. Pressure test confirmed this and also showed that the prop shaft seal was leaking. So I pullet it all apart for a complete reseal. Tried to document it all just to post the pics for people trying to do this in the future...but I got halfway through and my hands were all black and smelling like rotten fish oil, so I didn't want to touch my phone.

Anyway, for most of yall this should be common knowledge, but for everyone else: here you go.

propshaft seal leak

Click image for larger version.

Name: 20210508_104509.jpg
Views: 228
Size: 403.0 KB
ID: 486720

carrier nut tool

Click image for larger version.

Name: 20210508_111557.jpg
Views: 227
Size: 402.1 KB
ID: 486721

once the retaining nut is off using a puller to remove the carrier. Notice the thrust washer and wedges to keep the puller arms spread.

Click image for larger version.

Name: 20210508_105603.jpg
Views: 229
Size: 409.6 KB
ID: 486722

Click image for larger version.

Name: 20210508_105057.jpg
Views: 225
Size: 419.6 KB
ID: 486726

Not what you want to see when you pull the WP base. The base split in 2 pieces, this is not supposed to happen.

Click image for larger version.

Name: 20210508_103920.jpg
Views: 229
Size: 419.0 KB
ID: 486723

I have seen a number of times on here where this happens and people don't notice the part that stuck in the gearcase. Then they get a new base and it won't go in...case half of the old one is still in the case.
This part can be a pain in the a** to get out. I heated the tips of 2 big straight screwdrivers up red hot and embedded them into the plastic. Then poured water on it to cool it back down, then pried up and it came out. Simple but effective.

Click image for larger version.

Name: 20210508_104401.jpg
Views: 224
Size: 406.0 KB
ID: 486724

Click image for larger version.

Name: 20210508_104404.jpg
Views: 221
Size: 412.4 KB
ID: 486725

**25two.stroke** · 05-10-2021, 01:33 PM

The small size thrust washer for choppers with weed cutters will fit over the driveshaft in between the wp housing studs, this makes for a nice surface to gently tap on to seat the new base.
If you grease the Oring on the wp base it should slide in pretty easily. I like to use permatex so it hangs up a little.

Click image for larger version.

Name: Resized_20210508_112113.jpg
Views: 217
Size: 254.7 KB
ID: 486727

Click image for larger version.

Name: Resized_20210508_112016.jpeg
Views: 216
Size: 37.9 KB
ID: 486728

Click image for larger version.

Name: Resized_20210508_112150.jpg
Views: 216
Size: 259.1 KB
ID: 486729

**luv2gofast** · 05-10-2021, 03:13 PM

Don't lose the little square key when you pull the propshaft carrier.

**H2OPERF** · 05-11-2021, 06:45 AM

Must be nice to work on freshwater motors... in Fl half full of water usually means your spending half of the time on the job getting the carrier out and replacing half the internals.

**XstreamVking** · 05-11-2021, 06:58 AM

With salties, I just get the drill and bits out to remove the carrier and nut.....At least you still have the case threads, most of the time.

**H2OPERF** · 05-11-2021, 07:26 AM

Yea I do the same, its saves time and the threads, but the carrier still may take the torch.

**25two.stroke** · 05-11-2021, 10:03 AM

Originally Posted by H2OPERF

Yea I do the same, its saves time and the threads, but the carrier still may take the torch.

That is a salt only unit and it did take a little heating to come free but not much. 90% of the stuff I work on comes out of the salt. I see plenty that will not come apart...but mostly other manufacturers like Yamaha, Suzuki and Honda.
I don't know what it is about the salt here, or the salt in Florida, but every boat or engine I have ever seen shipped out here from Florida (aside from my BP from Chris Carson) was so salty you could hardly work on it.

If I was to try to try to pull the carrier on a 2000 opti lower from Florida that had never once been apart I bet that it would not come apart. You would have to crack the nut. However, if I went to pull a 2000 opti carrier that has been on this coast its whole life only 1 in about 50 would be stuck. Maybe its the water temp? Maybe people over there are lazy and don't flush their engines? Don't know but Florida parts are no good.

**H2OPERF** · 05-11-2021, 12:23 PM

Its the humidity here, I have to wipe the blades on our helicopters down everyday even if we don't fly anywhere near the water... there's enough wet salty droplets on the leading edge to make dinner with. lol.

**25two.stroke** · 05-11-2021, 12:32 PM

Click image for larger version.

Name: 123_1(4)(1).jpg
Views: 168
Size: 429.1 KB
ID: 486804

This was a block zinc... (we have salt)

**25two.stroke** · 05-11-2021, 03:03 PM

If you are ever installing a nose cone this is about where the pipe fitting should pop through. You gotta drill from the outside obviously, but this is where it should come out. Then fill the existing water cavity up to the hole that you drilled with epoxy so water doesn't sit in there forever.

Click image for larger version.

Name: 20210508_103926.jpg
Views: 166
Size: 421.3 KB
ID: 486811

**tnelsmn** · 05-12-2021, 05:16 PM

Wish I would've read through this before doing mine. I was able to pull it off with the book, but seeing it this way always helps. I just hope I have the shift shaft positioned correctly as the prop shaft went back in. Thanks for the write up!

PS I just used leftover poly resin to fill my water cavity after doing the cone. But I also plan to pull the lower for winter storage.

**25two.stroke** · 05-12-2021, 05:26 PM

As long as you have the shift cam in place and the correct side up you are all good.

**tnelsmn** · 05-12-2021, 05:47 PM

Originally Posted by 25two.stroke

As long as you have the shift cam in place and the correct side up you are all good.

I never pulled the shift shaft out completely, just pulled the bushing to replace the seals on it. Was worried that the shaft rotated in the process of that while the carrier was out.

**25two.stroke** · 05-12-2021, 11:20 PM

It don't matter if the shift shaft rotates, all that matters is you get it back into the shift cam...it is not timed and they don't have a missing tooth in the spline like some early merc shifters.
I guess I will take some more detailed pictures of the inner workings of a case...shoot maybe I should take a 30 min video of disassembling one completely and then putting it back together...just for reference.

I just don't know how to video edit...so it would be raw.

**NZ Sidewinder** · 05-19-2021, 11:47 PM

Hi
Im doing a LWP at the moment and have been pondering this issue of threaded holes into the water Gallery.
My Cone has 2 female outlets of half inch BSP each but its apparent that there is no way that this spot on each side of the gallery is wide enough for a Half inch BSP tapping drill which at a guess is around 3/4 inch.
So what pipe fitting thread is best to use? 3/8??