Johnson F5B-8 water pump questions

[Stroudwater1]

We have a closed skin tank cooled system. The water pump is probably the original from 1993. The impeller is a neoprene one. I’ve just replaced it. 
 

The front plate has become quite worn, and probably needs changing next time. It’s brass but there seem to be stainless steel replacements, not Johnson originals. Is this Ok or do we need a brass one? I presume stainless may wear less but does this mean the neoprene will wear more and cause trouble? 
 

There are small glycerine lubricant sachets available but am I right that is only for getting the new neoprene impeller refitted? I managed to do that without. I presume the glycerine gets washed out if used to put in a new impeller anyway? 
 

Do the bearing/ shaft need lubrication at all anywhere ? I think there are bearings but I’ve not removed the pump to explore where to lubricate. The gap that’s visible and pictured is quite tight. Access is relatively restricted without removing the pump if it does need lubricant. If it does need lubricant for the bearings which one is best for this?

 

This is a sideways view of the pump. 
 

[Tracy D'arth]

Oiler is the screw on the top.

Put the faceplate on back to front, after noting any numbers stamped in it.

[Tony Brooks]

1. Record the numbers on the front of the plate, rub the font on some fine emery paper/wet and dry to remove any burs from the numbers and letters. Then simply reverse the plate. That should give you another 30 years. I can't see anything wrong with stainless steel if you are happy to pay for it.

 

2. I think there are various rubber compounds available depending upon the temperature they are bing used in, not necessarily neoprene, so check the impeller data sheets f the vendor does not tell you.

 

3. The "glycerine" is to lubricate the impeller before it manages to suck water in. If one came with the impeller, I would use it, otherwise I would give the inside of the housing and impeller a squirt of washing up liquid just before I tightened the cover. I would do this whenever I fitted an impeller into a dry pump body.

 

4. I think that pump may have a wear plate at the opposite end of the chamber to the front cover, and it may be as worn as the cover. These can be reversed, but I would put a smear of jointing compound in the old worn face before refitting. You have to remove the screw in the last photo to take the cam out and the hook the wear plate out. If no wear plate it will be the pump body that is worn, but if it is pumping adequately, why worry. I would put some jointing compound on the back of the cam when refitting.

3 minutes ago, Tracy D'arth said:

Oiler is the screw on the top.

Put the faceplate on back to front, after noting any numbers stamped in it.

 

I am sure that you could use it for that, unless any stress in the bet impeller vanes moved the cam. That screw secures the cam in place, so I would not use it to inject the glycerine.