After disappointing service from the original raw water pump, I decided to switch to Oberdorfer pump.
This requires modification of the base to fit on M35B engines
Below album shows how to make this conversion.
You can puchase the original model that may need base modification  N202M-16
https://www.pumpsandpartsonline.com/shop/oberdorfer-pumps/rubber-impeller/rubberimpellerpumps/N202M-16
For $ 238.00  ( as of October 20210  free shipping. Additional spare parts, the impelled PT No 6593 $ 38.00 and the "O" ring PT No 9797-034  $ 3.00  may be purchased separately.

Seal replacement repair kit   PT No 11691  ( $ 65.00 )   is found here free shipping.
For full installation content with images CLICK HERE
See more C36 album images on pump replacement CLICK HERE
Seal Replacement  CLICK HERE

  Drop in replacement for Sherwood 908 Pump, also fits Universal M40 Engines. **   
*** Pump does not include gasket that goes between pump and motor. ***  

  ** Designed for Universal Series with Kubota Diesel **          
  *** Will work on following Kubota Models: Z482E, D722E, V1903E & V2203E ***
*** Pump does not include gasket that goes between pump and motor ****