Lower End Oil seal rebuild continued
Ok so with a little help from a valued contributor, Chet thanks so much.
I will slowly continue the threads in this post. I hope that if someone else
attempts this repair these notes and photos will be of use. Note These notes photos are offered as a suggestion only. I make no guarantee that if the procedure is followed there will not be breakage. The amount of corrosion will be different on each motor that the repair is conducted upon. I had to repair two T9.9 lower ends This first one had about 6 seasons use and the next about 12 seasons on it. One was harder to disassemble than the other because of different degrees of corrosion.
You will see a good example of this later in the thread.
The Lower unit oil chamber is sealed around the drive shaft by two seals that are installed in the oil seal housing.
And around the propeller shaft by two seals that are installed in the bearing housing. There are also two orings on the bearing housing.
See the following link and look up the schematic of your motor
http://www.yamaha-motor.com/partviewer/ ... s=outboard
Contrary to the last photograph you do not try to pry the oil seal housing out
until you remove the drive shaft.
To do this you must first extract the Bearing Housing.
I soaked the lower 10” of the lower end in a bucket of Double Strenght vinegar
for 3 days. I wanted to loosen as much corrosion or growth as I could because
I presumed that the inside flange of the Bering Housing would be scraping up
against the inside wall of the lower end casting
as it was extracted. If you have barnacles or other growth in that cavity
( the area open to the water) you need to get them out first. It turns out that there are
4 steps or levels machined into the inside of the lower end where the bearing housing resides so as you extract the bearing housing there is more space for it to slide out.
It is still best to have that water filled cavity as clean as possible before you attempt to take out the Bearing Housing.
Note remove all parts particularly the propeller nut from the propeller shaft
before you soak the lower unit in vinegar. The nut that was on my motor is brass.
It could be ruined by the electrolytic action of the vinegar.
I used a generic flywheel puller. It did not come with the 3 hooks,
I made them from 3/8 – 16 x 8” bolts. I bent, shaped and cut each hook. I heated and bent the bolt, holding it in a vice and hammered it over to make a sharp bend. About 92 degrees from straight ( so the finished hook is smaller that 90 degrees). I then squired off the inside angle of the hook with a file and them measured and cut the short end of the hook making sure it was just under ½ “ long. At this length the end of the hook should not scratch the inside of the casting as the hooks pull the bearing housing out. Make sure that the inside of the bend is squared off so that there is no fillet remaining in the bend.
You want to be as sure as you can that the hook is pulling up onto the thickest part of the housing (close to the wall of the casting and not on the thinner edge that is close to the inside of the housing where the hooks are sitting. On the second lower end I cracked that thin edge because the hook was pulling onto it. In inspecting the hook I found I had not squared the inside of the bend in one of the hook.
These three hooks need to be as Identical as possible.
The 3 hooks and center bolt on the puller, that is turned to extract the Bearing Housing must be kept in alignment with the prop shaft.
Photo 1 Extracting Bearing Housing