Trouble assembling ?75 1150 lower unit after replacing impeller

[s_schnei]

First time doing an impeller replacement myself. Have a Clymer?s Mercury Outboard Shop Manual, but it?s not very good, in my opinion.

I removed the lower unit and replaced water pump impeller gaskets and stainless steel plate without issues. Upon reassembly I can only get to with ?? of final position when metallic knock is heard. I rotate the flywheel clockwise, but I can?t get any closer than ??.

I suspect it may be the long copper tube. It came out attached to the upper water pump housing with the lower unit. How is that supposed to be aligned?

Appreciate any guidance you can offer.

 

[bassboy416]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

I have a 1974 mercury 1150 and just did the same job had same issue... I would spin the flywheel and it would definiitely drop into place better... Put it in gear and spun the prop... Would not spin in one direction and would click in the other direction in forward and wouldn't spin either direction in reverse..... Spun in nuetral... Seemed that the exhaust was the part that it was hanging up on... It would go on.... Make sure the shifter and driveline both line up in their places... would get within 1/2 inch to 1/4 inch and not work... Lubed up the exhaust gasket area and tightened slowly and with much finesse and even pressure with bolts and it came back together and worked great... took it out 9 hours yesterday... Just my experience... I'm a DYI newbie

 

[s_schnei]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

Prop spins freely in both directions when shifted in forward. Don?t think I have driveshaft engagement.
Tried rotating the flywheel, but the driveshaft does not engage. Something is keeping it from going up completely. I have put a light film of grease on both the exhaust seal and pipe to ease the assembly.

Question on your replacement?did the copper water tube come out with the lower unit? How did you align the copper tube when you put it back together?

 

[Big Fish Billy]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

Should be a rubber connector on both ends, I would take it off the lower unit and attach it to the upper housing, then when you're pushing the lower unit it up into position you can line it up on the lower unit.

 

[Chris1956]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

That water tube could be tricky to get back into the upper seal. Lube it up a bit and try to install it, twisting it a bit to get it installed into the seal. Then rotate it to line up with the waterpump output. Good luck.

 

[s_schnei]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

Well, I was afraid of that was going to be the case. None of the pictures on line showed the copper water line coming out with the lower unit, but wanted to that confirm here.

The copper tube goes into the upper pump cover which is plastic, I did not see a bushing at that connection, looks like just an O-ring, maybe a rubber sleeve in the housing, hard to tell. So I?m guessing the tube should pull out of the water pump cover?

There is also a white plastic sleeve; that must be to help align the lower end of the copper tube when putting the lower unit back on.

OK?with the tube off the water pump? installing the upper end of the tube will be a blind attachment. It will have to be by feel? trying to line it up with a bushing and try to push it on upper bushing. I can see why this will be tricky.

Is there any way to verify I have it in place correctly?

 

[Chris1956]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

I do not know of any way to verify the water tube is in correctly, except by feeling it go into the bushing seal. The water pump outlet uses the same seal, so you can at least get a look at it and a feel for how it fits. If you feel the end of the water tube bind on the edge of the seal, maybe a twist will free it up to seat properly.

 

[Fed]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

Do you know anyone who has one of those inspection cameras, tiny camera on the end of a flexible stick.
You could poke it up the tube and watch it go in maybe.

 

[s_schnei]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

No, don’t know anyone with inspection camera. I do appreciate the feedback though, it gives me a better understanding of what I need to do.

It will be a couple of weeks before I have a chance to give it another try.

 

[racerone]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

A good flashlight should be all that you need to see where the tube goes.-No need to work blind here.

 

[Chris1956]

Re: Trouble assembling ?75 1150 lower unit after replacing impeller

A flashlight is a good idea. Why not insert the tube into the seal you get with the waterpump kit and mark it with a sharpie? That way you maybe can see when it is in all the way.