1986 Johnson 150 J150TXCDC Gearcase Seal Replacement

[Terrapin]

I do not currently have any water leaking into my gearcase and my gearcase is functioning fine. I have not found any metal filings on the drain seal magnet during the annual fluid change over the 20 years I have owned this engine. However, as a preventive maintenance item, I am considering purchasing a seal kit and replacing the seals on my gearcase.

Is this a good idea or will I run into major problems removing the bearing housing from the prop shaft and the drive shaft bearing housing from the gearcase? The motor is used in brackish Chesapeake Bay water.

My water inlet screen could use replacement given some screen cracks and loss of some screening. Can this be replaced by just removing the driveshaft bearing housing and not the entire drive shaft assembly?

I’m trying to get an honest understanding of what I am up against replacing the gearcase seals. Last winter I successfully rebuilt my powerhead and the biggest struggle was powerhead bolt removal, having to cut and drill out a few.

 

[tplo]

You have to remove the prop shaft bearing carrier assy with a puller. also shift shaft seal and drive shaft seal under the water pump assy. It's a good idea to reseal it before you get water in and rust the bearings. If you rebuilt a power head then this should be much easier

 

[racerone]

The rubber seals do wear out over time.-----Give yourself a pat on the back for doing this seal kit.----Nothing to it if you did the powerhead.---I suggest a total " take apart " of the gearcase.-----Inspect bearing rollers above pinion gear.-----Water inlet screen is easy to replace.-----Pressure test before filling with oil.

 

[Terrapin]

Well, thanks for the words of encouragement. Once I get my gearcase holder made I'll dig into this gearcase seal replacement and will be back with many questions. In the meantime I'll be praying this comes apart without too much of a fight.

 

[Crosbyman]

you can always peek at these.... copy paste the string

https://www.youtube.com/results?search_query=1986+Johnson+150+J150TXCDC+Gearcase+Seal+Replacement

 

[Terrapin]

How do I determine whether the prop shaft bearings or driveshaft bearings need replaced? Is there a maximum amount of shaft runout I should look for with a dial indicator on the shaft? I don't see any specifications in my OEM service manual regarding shaft runout.

Per my post #1 above, I never had any water intrusion in the gearcase. In addition, I recently pressurized the gearcase with 16psi for 4 days without loss of pressure and applied a vacuum of 15 inHG for 4 days without any vacuum loss.

 

[racerone]

If it holds those pressures it is all good.---Fill with the best BRP specified oil for it and go fishing.

 

[Terrapin]

I couldn't leave well enough alone and decided to replace all of the seals on my gearcase. The shift rod and driveshaft related seals are replaced. I pulled the propeller shaft bearing housing and plan on replacing the two prop shaft bearings in addition to the seals.
The front of the bearing housing has two milled slots to get the jaws of a modified bearing puller under the bearing for removal. However, the rear of the bearing housing does not have milled slots to get the jaws under the bearing. What is the secret to pulling this rear bearing?

 

[racerone]

If you heat the bearing housing ( boiling water ) you may be able to tap the bearing out.

 

[Terrapin]

If you heat the bearing housing ( boiling water ) you may be able to tap the bearing out.

Thanks, I have to modify my puller jaws to .200" wide to get in the front slots which are only about .210" wide.
I'll try the boiling water method on the rear bearing, but there isn't much of an exposed surface to tap on. Once I start tapping I'm committed to getting it out.

 

[racerone]

This job should be easy !

 

[Terrapin]

OK, I modified my puller to .200" wide and successfully pulled the bearing. Racerone, I used your boiling water technique and a 1 1/4" diameter sink tailpiece to tap out the rear bearing.
Any tips for the new bearing install? I have the bearing install tools. Is it necessary to freeze the bearings prior to pressing them in place, or just press them with light oil lubrication at room temperature?