Lower Unit Questions 1990, 90hp outboard

[zimmer62]

I've got a 1990 force 90hp outboard.

I'm rebuilding the powerhead, however I decided to take a look at the lower unit.

Since this is my first rebuild, I'm really not sure what to look for on the lower unit.

I drained the oil, and it seemed clean (no water) however a nylon washer came out with the oil... "yikes" Seems like it might be a good idea to rebuild this as well.

When the unit is in gear, I can turn the prop and see the drive shaft spin, but it's pretty hard to spin, is this normal? I can't spin the drive shaft by hand in gear, or in neutral. Also in neutral, the prop will spin, but not as freely as I expected, what would be a normal amount?

So... If I need to rip this open what should I replace, is there a kit for just replacing everything?

 

[roscoe]

Re: Lower Unit Questions 1990, 90hp outboard

Replacing everything? You could buy a new motor for what that would cost.
Just get a seal kit and put in new seals if you want to. Get a factory or Clymer service manual first, and read up on it. Then decide if you want to buy all the special tools you will need.

 

[zimmer62]

Re: Lower Unit Questions 1990, 90hp outboard

Got ya, yeah, I don't want to waste money on replacing things that don't need replace ment.

Manual is on it's way.

Any idea what that nylon washer was doing in the oil I drained? Any anwser on if it is normal to require so much force to turn the crankshaft by hand?

 

[Jimmyz123_]

Re: Lower Unit Questions 1990, 90hp outboard

My recommendation is for you to get a shop manual rather than the Ones you can buy in the stores. I have the Clymer manual and it is helpful, but there is a lot that it leaves out. Once you play with the motor a little and the work that you are planning on doing, you'll be your own service tech. Good luck.

 

[roscoe]

Re: Lower Unit Questions 1990, 90hp outboard

THe seals may be wedged in too tight, twisted, etc, causing the extra tension.

The nylon washer is most likely just the sealing washer that goes on the drain and vent screws. Some used a fiber washer, some a nylon washer.

It should be replaced whenever you change the gear oil.

 

[zimmer62]

Re: Lower Unit Questions 1990, 90hp outboard

Thanks for the answer on the seals, and the nylon washer, it puts my mind a little bit at ease. I'll tear it down sometime this week and get a better idea of what's happening.