trouble seating lower impeller housing

[benlange]

I have gone through 2 upper impeller housings after warping them around the screw holes. The lower impeller housing does not want to seat properly. I have a pre-alpha merc outdrive, inline 6 165hp. It seems like it is the wrong housing, but two seperate dealers and pics online show this to be the one. Installing by hand with some pressure yields a 1/4" gap between botom of impeller housing and lower outdrive housing. Is there something I am missing here?

Thanks for any help you can give!!!

 

[ziggy]

Re: trouble seating lower impeller housing

hard to say. i've not had the issue with mine. only thing i can think of is that all the gaskets and the plate might add up to a 1/4'' thick. have you got them all in there proper places?
are you turning the drive shaft cw while pushing the housing down onto the water pump base? did you lub the impeller with soapy water prior to installing the water pump housing over the impeller.

 

[benlange]

Re: trouble seating lower impeller housing

It is the lower impeller housing that is not seating to the lower unit. The upper housing is seating ok.

 

[Bt Doctur]

Re: trouble seating lower impeller housing

whats the part number?
A lower housing for Alpha will not fit due to a difference in the seals.

 

[benlange]

Re: trouble seating lower impeller housing

pn 18-3320 for the pump kit

 

[Bt Doctur]

Re: trouble seating lower impeller housing

lower units that have a pre-load pin on the driveshaft use Sierra 18-3417, Merc # 46-57234A1
Drive with no preload pin use Sierra 18-3420, Merc # 46-44292A3

 

[benlange]

Re: trouble seating lower impeller housing

Thanks, I will try that one this afternoon. I do have the preload pin.