79 Merc 70 HP (changeing impeller questions)

[69starcraft]

Hello again

so I took the advice from here, bought the water pump rebuild kit for $40 (local, in stock, so I'm not bitchin)

Glad I did!!

To quickly answer a question from my first post NO this motor has never been run in salt water ever. Only upstate NY clear lakes...Not like the brown lakes we have here in NC

Also before I did this I noticed the pisser water was way hot at idle. So I opoted to change impeller.

So I took the lower unit off last night. Impeller is hard, shaped like a starfish (bad) and cracked up when I tried to straighten the fins.

I got the kit today, imagine my surprise they had it in stock for a 1979 engine.

I'm ready to put it back together, and I notice there is an O-ring in the package. I am a decent mechanic (cars) and very mechanically inclined and when I took it apart last night I found no O-ring.

So my question is anyone know what this goes to? The kit is for "multiple" engines, and does include two sets of upper driveshaft seals depending on your model/hp and I figured that out. There is even a bulletin in the package based on your model that states which seal to use. There is no mention of any 0-rings

Also, any advice for when I put the lower unit back on? The guy at the "dealer" stated he would not change the prop seal until after I actually run the boat in the water. Stated it takes special tools to do so, and he wouldn't bother even if it was his boat until after he ran in water (not in driveway) and then checked it again. Stated it might be fine.



Well, thanks again

I am actually outside working on it now, looking for an o-ring or where it might go, and will keep checking back


Dave in N C

 

[Laddies]

Re: 79 Merc 70 HP (changeing impeller questions)

If the o ring is about 1 7/8 dia. it's for the bottom pump housing

 

[69starcraft]

Re: 79 Merc 70 HP (changeing impeller questions)

hmm...ok, so I should probably change that too!

ok, so next question is how to get the bottom of the pump housing out of the lower unit? it seems to be solid and in good shape, but it didn't respond to any tentative prying and appeared to be stuck fast.

Also am assuming when I put the impeller housing back on the fins should be clockwise right?



any more advice?


thanks

dave

 

[diaric]

Re: 79 Merc 70 HP (changeing impeller questions)

if your not experiencing any water in your lower unit lube, its probably best to leave it alone. usually have to soak around the studs with penetrating oil to free up corrosion, and chances are it will crack when you try to pry it free. someone else will have to answer the impellor rotation, i think your right, but i usually have to mark the top of the old one before removal to ensure i do it right

 

[jebeebe]

Re: 79 Merc 70 HP (changeing impeller questions)

There is an 0-ring around the lower houseing and it goes in tough and after a few years comes out even tougher. I just replaced mine on a 60hp. There is a berring below the pump and the 0-ring and the inner seal keeps the water out of the lower unit. The previous post is right . If it ain't broke don't fix it.
Good luck...............Jerry