Success changing impeller!![but have question]

[Rocky4052]

1966 Merc 50hp. Finally got water Pump top cover off and changed impeller and gaskets.I have not put lower unit back on yet --untill I know tell-tale hole is clear. OK,here goes. rubber hose is clear. Ran a wire up thru pipe from bottom and it reaches just into motor and stops. [hits something metal?] Ran wire into plastic nipple where hose attaches, and it only goes in a little way. Tell-tale hole it self is clear. I shot compressed air up into pipe from bottom, and cannot feel any air coming out of the plastic nipple. Do I have a problem? Or is it that I am a newbie and have to read up more on the workings of an outboard motor?
I'm thinking that the motor has to be running, and once the [ water jacket?]
fills up with water, then it comes out tell-tale. Am I anywhere near right??

Thanks, Dan.

 

[tmcalavy]

Re: Success changing impeller!![but have question]

'Purt near right. Put the LU back on and run in it a barrel of water or a pond or at the boat ramp with the leg in the water. If the pump is doing its job the water jackets should be water temp. not hot to the touch. If you can't hold your hand on the jackets, it's too hot. Those old Mercs don't have a thermostat so it's a straight through affair...water in the inlet, through the pump, up the water tube/pipe, into and around the cylinder water jackets and out the discharge.

 

[Rocky4052]

Re: Success changing impeller!![but have question]

Thanks for the reply. Just wanted to verify before I put it back together.

Another step closer to the water!!! Dan

 

[diaric]

Re: Success changing impeller!![but have question]

congrats rocky, how did u finally get the cover to break free? u should be able to test the water flow by putting the water tube in the powerhead and hook somw water too it see where it comes out. good time to check the condition of the tube and make sure its not rotted

 

[Rocky4052]

Re: Success changing impeller!![but have question]

Got the cover free by drilling a few small holes into the corrosion around the stud and sprayed in liquid wrench. I then used a dremel tool to make a slot in the side of the housing and then was able to drive it up using a hammer and screwdriver. The rest of it went smooth. Well, I haven't put it back on the motor yet. I had put it in forward gear before I dropped the LU---and then scribed it to keep things lined up. If you have any tips on the reinstallation, let me know. I'll check back later.
The impeller was toast!! Thanks, Dan

 

[diaric]

Re: Success changing impeller!![but have question]

get a third hand to help start the nuts while u hold the lower unit. your drive shaft probably won't line up. slide on the prop and rotate it until it all slides together, if that way(easier) doesn't work, then rotate the flywheel till it aligns. did you take the bottom of the waterpump off too? I don't imagine you did as you can't get a replacement.

 

[Rocky4052]

Re: Success changing impeller!![but have question]

no--didn't touch the bottom part. Didn't want to stretch my luck unless I had to....... Thanks, Dan