Water Pump Kit Question - (Merc 90)

[CharlieZulu]

Hi folks:

First time attempting to replace the impeller in my Merc 90. I bought the kit from Quicksilver and watched the various videos on You Tub, etc so I hav a reasonable understanding of what I'm getting into.

I understand the two gaskets and the faceplate and the keyway, etc but what are all these extra parts for?? One of them is apparently a 'tool', and then there are two red o-rings, plus three yellow washers and one red one. There is also a black piece. Pics below:

 

[CharlieZulu]

Re: Water Pump Kit Question - (Merc 90)

Anyone?

 

[Bob_VT]

Re: Water Pump Kit Question - (Merc 90)

Well..... there are shaft seals and various motors use various parts. It is easier for Merc to package the parts as a whole and yes.....there are times when you get extras not related to your motor. That impellar kit will fit MANY motors.

 

[Silvertip]

Re: Water Pump Kit Question - (Merc 90)

I'll shed a little light on this topic since I've spent more than just a little time with part numbers. When you order a "KIT" of any kind, the package of parts carries a part number which you use to order that collection of parts. Each part that makes up that kit also carries a part number. When I was dealing with this stuff it cost a company roughly $10,000 just to "assign" a part number whether that number was for a kit of parts or just a single part. The cost covered the expenses involved in maintaining the related documentation (drawings, specs, etc) for the life of that part or kit. So think about this -- if a separate, engine specific kit was made for each engine with the only thing differeing was the size of one O-ring for example, you can imagine the maintenance cost for the corporation due to the sheer number of kits required. If one kit can serve two, three, four or a dozen engines, it is much cheaper to create one package to serve those engines (being reasonable of course with parts counts) rather than create a whole bunch with a great deal of duplication. It is cheaper to throw away an o-ring or two that aren't needed than to create two separate complete kits just because of those two parts. Carburetor kits are another example of where this process occurs. Engine gasket sets is another. This is a very common practice in nearly every manufacturing spare parts organization. Normally the included instructions tell you what engine serial or model numbers require which parts.

 

[CharlieZulu]

Re: Water Pump Kit Question - (Merc 90)

Thanks guys.... one more question re the face seal. The instructions state to slide the face seal down onto the driveshaft with "lips facing downward"...... I assume this means the flared end of the seal?? See pics:

OR

 

[jeffersondodson561]

Re: Water Pump Kit Question - (Merc 90)

The upper picture is the correct way to install the seal, I would lube the inner part of the seal with soapy water and put it on the driveshaft, bring it all the way down until it almost touches the housing and with that plastic piece touching the vein of the impeller on your picture; that is the tool for installing the seal, put it over the driveshaft and while lifting the gearcase using the weight of the gearcase push down on the plastic piece, this puts the seal on properly accounting for the preload of the driveshaft.