Talk:Mud motor

This is written in the first person, and 3.1442 degreees seems a little arbitrary
 * 4 decimal places of precision is ridiculous. (I wonder where it came from?).  RJFJR (talk) 19:08, 21 November 2008 (UTC)

There are two types of mud motors: PCPD motors and turbodrills, reference: Standard Handbook of Petroleum and Natural Gas Engineering, page 4-358 "Mud motor. Usually a positive displacement or turbine-type motor, positioned above the bit..." `a5b (talk) 09:56, 6 January 2015 (UTC)