1994 Ford Ranger Engine temp not getting above cool.

Here's the TSB from Ford on this problem, FLUSH enging real well and use the new Ford Tstat, part number YS4Z-8575-AA
2.3L/2.5L - DTC P0125 - LACK OF HEAT FROM HEATER TECHNICAL SERVICE BULLETIN Reference Number(s): 99-16-2, Â Date of Issue: Â August 9, 1999 Related Ref Number(s): 99-16-2 ARTICLE BEGINNING CONDITIONS LAMP - MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED WITH DIAGNOSTIC TROUBLE CODE (DTC) P0125 STORED IN MEMORY - LACK OF HEAT - VEHICLES WITH 2.3L OR 2.5L ENGINE COOLING SYSTEM - LACK OF HEAT - VEHICLES WITH 2.3L OR 2.5L ENGINE APPLICATION Model(s): Ford: 1993-1999 Ranger Bulletin No: 99-16-2 Date: August 9, 1999 ISSUE The Malfunction Indicator Lamp (MIL) may illuminate with Diagnostic Trouble Code (DTC) P0125 stored in memory, and/or a lack of heat with the climate control may occur on some vehicles. This may be caused by sand from the engine block casting getting trapped within the thermostat mechanism. ACTION Replace thermostat with a revised thermostat. Refer to the following SERVICE PROCEDURE for details. SERVICE PROCEDURE 1. Verify concern. 2. Flush the cooling system as outlined in the appropriate year Ranger Service/Workshop Manual. 3. Replace thermostat with revised Thermostat (YS4Z-8575-AA). Refer to the appropriate year Ranger Service/Workshop Manual for thermostat removal and replacement procedures. 4. Fill cooling system with appropriate mix of Engine Coolant (E2FZ-19549-AA) and water. 5. After repairing, verify normal engine operating temperature and normal heat air flow through the climate control. Page 1 of 2 2.3L/2.5L - DTC P0125 - LACK OF HEAT FROM HEATER -1994 Ford Ranger

First get a pan that is made for draining radiators, then drain it into the pan, then flush it out according to the manufacturs instructions.