Fresh Water Pump Rebuild?

[Play'N Hooky Too]

Not sure if this is a question that could be answered here but... I just ordered a rebuild kit for my freshwater pump (8V71TI engine). When comparing the parts in the kit with the ones extracted from the pump I found that the impeller in the new kit does not have a ceramic insert on the engine-facing side (the side that rides against the water seal) nor does it have a cavity to accommodate a ceramic insert (a part that can be ordered separately along with the adhesive washers). The old impeller has a part number stamp (5123146) that doesn't match any of the numbers listed in the 71 Series section of the DD parts manual (FP Diesel Manual downloaded from Boatdiesel.com). The new impeller part number (FP-2350599) matches the one listed for the "Hi-Capacity" pump which, from the exploded diagram, appears to be the one I have and is also the one indicated for my 8V engine.

What concerns me is that the repair manual discusses at length the importance of the ceramic insert and the procedure for replacing it in the case where the old impeller is reused. So my question is....do I have the wrong part or is the ceramic insert something that was discontinued? It would seem that if it was necessary it would have been attached to the new impeller or included with the rebuild kit.

Thanks
-Alan

 

[KPTIM]

There are two type pumps used on the 8V71.
Take a look at this link.
It will give you a guide which to use.

https://dieselpro.com/detroit-diesel-parts/8v71-engine-turbo/fresh-water-pumps.html

One other point, when you put the pump back in the engine you have to set the back lash on the drive gear. This procedure is pretty clear in the DDC manual. If you don't have it I can send you the factory procedure for setting the gear backlash.

 

[Pls]

It sounds like the rebuild kit contains a unitized seal. It can be used in place of the old lip seal but you will need a special tool to press the seal into the pump housing and on to the pump shaft at the same time.

 

[Play'N Hooky Too]

There are two type pumps used on the 8V71.
Take a look at this link.
It will give you a guide which to use.

https://dieselpro.com/detroit-diesel-parts/8v71-engine-turbo/fresh-water-pumps.html

One other point, when you put the pump back in the engine you have to set the back lash on the drive gear. This procedure is pretty clear in the DDC manual. If you don't have it I can send you the factory procedure for setting the gear backlash.

Thanks for the reply. The pump I have is the one shown in Picture #3 and the kit that I have is the same as shown in Picture #4. Notice the impeller in Picture #4. This is the same as the one in the rebuild kit that I have. The old impeller that I removed from the pump looks exactly the same except it has a ceramic insert bonded to it. (The impeller in Figure #5 has a ceramic insert but is a different configuration.)

 

[Play'N Hooky Too]

It sounds like the rebuild kit contains a unitized seal. It can be used in place of the old lip seal but you will need a special tool to press the seal into the pump housing and on to the pump shaft at the same time.

Thanks for the reply. I can see that you are correct about the unitized seal. From the BoatDiesel.com forum I have been informed that use of the ceramic seal in the pumps was discontinued around 25 years ago. I wonder if it has been that long since the pump was rebuilt?

.....One other point, when you put the pump back in the engine you have to set the back lash on the drive gear. This procedure is pretty clear in the DDC manual. If you don't have it I can send you the factory procedure for setting the gear backlash.

The factory procedure for setting the backlash would be greatly appreciated.

Thanks
-Alan

 

[KPTIM]

I know that the information in this link is very 8V92 intensive but I think you will find the information transfers to the 8V71.

https://www.wanderlodgeownersgroup....NE SERVICE MANUAL/Sect 5 - Cooling System.pdf