HP Pump Problem

[washman9]

we have a Giant model LP 123 that was dripping water and getting some water into crankcase. replaced all low / high pressure seals but dont know how to approach removal of ceramic plunger / crankcase seals. is there a special tool needs to remove the crank seals or do I simply remove bolt from end of ceramic plunger and pull out gently with channel locks / pliars. any tips would be appreciated.

 

[MEP001]

The crankcase seals aren't your problem. They just keep oil in the case, not water out. You likely have a cracked plunger or bad seals on the plunger bolts.

 

[washman9]

thanks for info. how difficult is it to remove the plunger? if I remove end bolt will it slide right off or do i need an extractor type tool?

thanks

 

[MEP001]

It should come right off, but there's a chance the piston has rusted and the plunger will be very difficult if not impossible to remove without breaking it. I don't know if that pump has steel or stainless pistons. Worst case, order a couple plungers and all the seals, washers and new bolts from somewhere you can return the plungers if you don't need them.

 

[washman9]

the plungers themselves appear to be ceramic. this may make it even more difficult to extract without breaking them.

 

[MEP001]

They are ceramic. Like I said, they'll either slide right off or will be rusted on. I've had some luck in the past with a towel wrapped many times around the plunger to protect it while I used channel locks to twist it and work it off, but make sure you examine the plunger for cracks. The rusting tends to break them, and the cracks tend to make them rust on solid, so in either case it's no loss if you have to break it to get it off.

 

[MEP001]

use a 8-mm or 12mm socket and wrench to remove the crankcase.

You probably mean to remove the manifold retaining bolts and the manifold.

Here's the manual:

http://www.giantpumps.com/pumpspages/pumpmanuals/LP122A_LP123_LP255.pdf