[achilles555]

Hello all. Just changed the impeller, gaskets, and top of the housing on Water Pump of 1987 Mercury Classic Fifty 45 HP 4 cyl. (serial OB161091). I ran into a couple "hiccups" along the way, and need some advice. Here goes:

• After I completed installation and got everything back together, I tested my forward, reverse, and neutral, and here's what I found.
- Neutral works fine. Prop spins both directions freely
- Forward works fine. Prop spins clockwise correctly (makes a clicking noise when spinning), and won't turn in the opposite direction. No resistance.
- Reverse is a different story. The prop spins in reverse, but only with much force, and you can hear the pistons pumping and the compression sound in the chambers. It does not spin in reverse (counterclockwise) freely. Does this sound normal?

• My water pump does not have a water sleeve. The water tube runs straight into the top of the Pump Housing. Is this normal?

• The top of my Drive Shaft has a pin, and then just below the pin andthe top teeth, 2 rubber seals go over the end of the Drive Shaft, but not all the way down to the water pump. The are slotted to fit the top of the Drive Shaft. I took them off, but forgot to note how they go back. My manual is no help. I put the larger round seal on first, and the smaller graduated seal on top of that. Can anyone confirm that this is correct? What are those rubber seals for, anyway?

I guess that's it. I want to get this right before I take her out for the first time. Any help you guys can give would be much appreciated. AC.

[This_lil_fishy]

Heh, that's a few questions.

1, Yup, mine does that too.

2, Yup, just make sure the seals in the top of the housing are in place. Well, a rubber seal, and a nylon washer.

3, I didn't have two rubber sleaves, but a rubber sleave and a nylon sleave. Seems you have it together right though. Those are there just to prevent moisture from getting up in there and rusting the shaft and crank together. A mechanic friend of mine just tosses them and puts some water proof grease on the splines. To each their own, I put them back on. The pin at the top should be spring loaded (you should be able to push it in, requiring quite a bit of force, and then it will pop back out). It keeps downward pressure on the drive shaft.

Ian

[achilles555]

Hey Ian. Thanks for the info. I always get nervous cinching that lower unit up. Alwys seems like it should go in easier...instead of having to cinch it up with the bolts. Anyway, I put a new water pump top in when I installes the impeller. I'm hoping that nylon seal and washer youare talking about come already installed in the water pump top.

One last thing. Do you have any idea what the 2 tiny O-rings in the impeller kit are for? Thanks so much for the help. Aaron

[This_lil_fishy]

When I did mine the top housing had the rubber gasket but NOT the nylon washer, so I had to re-use the old one. I ordered a complete kit and was left with a number of left over o-rings. I believe they include all of the o-rings for different engines as some require them, and others don't. You probably should have replaced the lower housing too, as there are two seals in there that prevent gear oil from coming up through the shaft. The lower unit should slide in nicely, without much fuss. If you are forcing it up with the nuts, something isn't lining up properly or is binding.

It is a big pain in the backside doing this job, but not technically difficult. Just a bit time consuming and fiddly.

Ian