Huh...spare parts....I'll just toss those

[This_lil_fishy]

Okay, I won't toss them...but still...trying to figure out where they belong. When I dropped the lower unit to rebuild the water pump I found half an o-ring (about the diameter of the drive shaft), a rubber 'seal' the has drive shaft splines inside about half way down inside then ends sharp. A plastic 'seal' that is similar to the rubber one, but the splines are tapered at one end. A rubber tube (about 2") that was about half way up the copper water tube doin nothin. Then there was another rubber 'O-Ring' that was about 1/4" thick (almost like a piece of hose) on the drive shaft sitting just on top of the water pump housing.

I believe, that the plastic ring goes onto the drive shaft and mates with the tapered splines, then the rubber one goes on top of the (the outside diameter is tapered btw) with the tapered side up.

The rubber tube, I have no idea what it's purpose is, I've inserted the copper tube into the powerhead, and now it will not come out, so I guess it has a nice seal to it...althought the tube fell out when I dropped the lower unit, so I dunno (stuck in the pump).

The O-Ring, I have no idea where that came up. It's fairly thick, but it's all chewed up and half of it is missing...

The 1/4" thick 'o-ring', well it doesn't seem to suit any purpose...but I guess it's there for a reason. It didn't easily slide off the drive shaft, but definately not groove there.

Any input would be appreciated....

1986 Merc 50, 3cyl 2stroke.

Ian

 

[jeffdjpeat]

Re: Huh...spare parts....I'll just toss those

there is a slightly tapered plastic or rubber peice that has spline grooves that goes on the top of the drive shaft where it mates to the motor, another 1/4 inch thick rubber o-ring, that slides down the drive shaft and sits on top of the water pump housing, the 2 inch long rubber peice on the copper tube i wondered the same thing, i just slid it back on, dont know what it does. and a plastic tube to help line the pump housing up with the copper intake tube during re-installation. i also had one very thin rubber o-ring i didnt see any come off, and i didnt put the new one on. mine pees like a race horse now. the kit i bought had about a dozen other seals for around the prop shaft, etc... those ones i didnt use, i didnt get that far into the lower end.

 

[This_lil_fishy]

Re: Huh...spare parts....I'll just toss those

Thanks, now I need to figure out why mine has both the plastic and rubber splined pieces, about 3/4" long each. LoLs...looks like someone else has been tinkering with my motor before me.

Ian

 

[This_lil_fishy]

Re: Huh...spare parts....I'll just toss those

Anyone know how much gear lash should be in these units? Should I feel any at all when it is in gear. Figure i got it this far, may as well make sure it isn't going to blow out on me in the water.

Mine seems to have about a 1/16" movement in the vertical drive shaft. Seems excessive to me...but who knows.


Ian

 

[jeffdjpeat]

Re: Huh...spare parts....I'll just toss those

my drive shaft would move probably almost move 1/4 inch. but its running fine, after probably 6 hours of water time, no issues. weather or not that is right, i dont know. as for having a plastic and rubber piece with the spline grooves in it, i know when i took mine apart, someone had the old one still sitting up in the bottom end, they never fished the thing out, it tends to fall off when you pull the bottom end, i kept wondering what i was getting caught up on pushing the lower unit back on, and there it was, another bushing stuck up there.

 

[CharlieB]

Re: Huh...spare parts....I'll just toss those

Gear 'lash' can be a bit, the pinion depth is the real determining factor in setting up the gear tooth contact. Don't worry about it. As long as there isn't major steel on the LU drain plug magnet you are probably OK.

Some models used various methods of sealing the splined shaft to the engine in attempt to keep carbon accumulation from getting into the splines. Some models use none.

The long rubber hose (sort of) on the water transfer tube was used to reduce harmonic vibration in the tube.

 

[This_lil_fishy]

Re: Huh...spare parts....I'll just toss those

Gear 'lash' can be a bit, the pinion depth is the real determining factor in setting up the gear tooth contact. Don't worry about it. As long as there isn't major steel on the LU drain plug magnet you are probably OK.

Some models used various methods of sealing the splined shaft to the engine in attempt to keep carbon accumulation from getting into the splines. Some models use none.

The long rubber hose (sort of) on the water transfer tube was used to reduce harmonic vibration in the tube.

Wow, that makes perfect sense, and I would never have thought of it. Thanks!

Ian