impeller replacement

[Keeline]

1971 mercury 1150, minimum required for impeller replacement.

 

[Mi duckdown]

Re: impeller replacement

more info.

 

[tazrig]

Re: impeller replacement

If your asking how often it should be replaced a good rule of thumb is every 2 years. Could you be more specific?

 

[Keeline]

Re: impeller replacement

more info.

This engine has been setting for some time. I got it started but no P spout. My guess is the impeller is frozen or chewed up. My question is, how to to simply drop the lower section and have access to the impeller. The repair manual is not particularly clear. Can the lower unit be dropped by undoing the 6 bolts?
Keeline

 

[Texasmark]

Re: impeller replacement

This engine has been setting for some time. I got it started but no P spout. My guess is the impeller is frozen or chewed up. My question is, how to to simply drop the lower section and have access to the impeller. The repair manual is not particularly clear. Can the lower unit be dropped by undoing the 6 bolts?
Keeline

Yes on the bolts. One front, 4 on the sides, and the one most overlooked is beneath the trim tab. Mark the location (deflection) of the tab before you remove it then with a hex socket, forget the size, look down in the hole on top of the rear of the mid section just above the rear of the LU where a plastic plug about the size of a nickel is located and remove the plug and the screw beneath. That drops the tab. Then look from below up in the area the tab covered and you will see #6.

On the nuts on the side, you have to work your way down to get them all the way off; the mid section fins are in the way to do it all at once. Course that's not all bad as when you are breaking the sections apart, that helps to keep the LU from falling out on the floor.....when you are lucky enough to get an easy separation.

There are 3 things holding the LU once the bolts/nuts are removed/loose: The drive shaft, water tube, and shift shaft. With luck you can wobble it out. Be careful prising or banging on the alum LU and mid section, especially the plates, like the AV Plate just above the prop. The alum is cast and brittle. It will not take to any pressure and when you break some of them off they look ugly.

Once you get it all off and fixed come back and we will walk you through getting the 3 interfaces lined up for reassy.

Mark

 

[Keeline]

Re: impeller replacement

Yes on the bolts. One front, 4 on the sides, and the one most overlooked is beneath the trim tab. Mark the location (deflection) of the tab before you remove it then with a hex socket, forget the size, look down in the hole on top of the rear of the mid section just above the rear of the LU where a plastic plug about the size of a nickel is located and remove the plug and the screw beneath. That drops the tab. Then look from below up in the area the tab covered and you will see #6.

On the nuts on the side, you have to work your way down to get them all the way off; the mid section fins are in the way to do it all at once. Course that's not all bad as when you are breaking the sections apart, that helps to keep the LU from falling out on the floor.....when you are lucky enough to get an easy separation.

There are 3 things holding the LU once the bolts/nuts are removed/loose: The drive shaft, water tube, and shift shaft. With luck you can wobble it out. Be careful prising or banging on the alum LU and mid section, especially the plates, like the AV Plate just above the prop. The alum is cast and brittle. It will not take to any pressure and when you break some of them off they look ugly.

Once you get it all off and fixed come back and we will walk you through getting the 3 interfaces lined up for reassy.

Mark

Thanks for response. Will work on it this weekend and get back to you.
Keeline

 

[Keeline]

Re: impeller replacement

Mark: The lower unit slipped right off. Mud dobbers were the problem. New impeller in and pump looks good. Two questions.
There was a neoprene ring, broken, that I think went on the shaft above the pump called a slinger I think. Where is a source for purchase? Second, is there a way to line up the pump flow pipe when pushing the lower unit back up?
Keeline

 

[oldman570]

Re: impeller replacement

I get a O ring at the local parts store that fits the shaft fairly tight it a repair kit was not bought. This will usally do the job for the slinger ring. I have found it easier to replace the LU if the water tube is put in the motor upper leg gromet first, then guided it the gromet on the pump housing on the LU. When replacing the LU it is easier if the shifter is in the netural position and the LU shift shaft is the same.I do this before I pull the LU off the motor. As long as neather have been moved while working on the unit , it should go back together fine. Always put some grease or Never Sizees on the splines of the driveshaft where it goes into the motor crankshaft. Make sure that there is none on the end of the Driveshaft. Older motors as yours often have steel shafts that will corrode and can make removal of the LU almost impossable at a later date.JMO
Oldman570

 

[Chris1956]

Re: impeller replacement

Keeline, A waterpump rebuild kit will come with the parts you will need. As a minimum, replace the impeller, wearplate and two gaskets, (one on either side of wearplate). The water tube guide tube (white plastic) fits into the output of the waterpump and allows you to mate it with the copper water tube. The slinger will be in the kit as will be waterpump base gasket and Oring. Replacing them is a good idea, if you do know know when it was last done. Gaskets for the drain and fill plugs are aloso included in the kit. Use them.