Frequently Asked Questions

  • Fan Clutches
  • Transmission Oil Coolers
  • Service Bulletins
    • HOW DO I KNOW IF MY FAN CLUTCH NEEDS TO BE REPLACED?

      These are the most common symptoms of a failed fan clutch:


      • Leaking fluid - Oily build up around the bearing or thermal spring
      • Bad bearing - Seized, turns rough or has excessive play, (more than 1/4" at fan tip)
      • Worn thermal spring - Spring is loose

      Some fan clutches will show no visible indication of a problem yet may still be faulty. The following may also indicate a faulty fan clutch:


      • Fan spins excessively - Three or more times when hot engine is shut off
      • Poor air conditioning - At low speed or excessive high side pressures
      • Doesn't engage - Fan speed does not increase or "locks up" when the engine is hot
      • Does not disengage - Fan clutch won't slow down when the engine is cold
      AT WHAT TEMPERATURES DO FAN CLUTCHES ENGAGE?
      • Most fan clutches engage at about 170° F air temperature (about 180-190° F engine temperature). They reduce the temperature about 20° F before disengaging.
      WHAT IS THE DIFFERENCE BETWEEN A STANDARD, HEAVY AND SEVERE DUTY FAN CLUTCH?
      • Each fan clutch type is designed to simulate the performance of the original equipment clutch that it replaces. All fan clutches are for specific applications and should be applied only on the application for which they are cataloged.

      Standard Duty Thermal


      • Turns the fan 50-60% of shaft speed when engaged. Used with fans with lighter pitch. (1-1/2" of pitch) Flat plate impeller design with 30 Sq. In. of working surface.

      Heavy-Duty Thermal


      • Turns the fan 80-90% of the shaft speed when engaged for increased cooling. Used with deeper pitch fans. (2 1/2" of pitch). Land and groove design with 47 Sq. In. of working area allows higher operating RPM's.

      Severe Duty Thermal


      • Turns the fan 80-90% of the shaft speed when engaged. Used with deeper pitch fans. (2- 1/2" of pitch). Land and groove design with 65 Sq. In. of working area. Larger working surface provides cooler running and longer life expectancy.
    • THE TRANS COOLER IN THE RADIATOR IS LEAKING AND IS EXPENSIVE TO REPAIR. CAN I USE A HAYDEN TRANSMISSION COOLER TO ELIMINATE IT?
      • Yes. Always choose one of the larger Hayden coolers when eliminating the radiator cooler to compensate for the loss of cooling from the radiator. In most installations we recommend use of the radiator tank cooler to provide maximum cooling and to comply with most manufacturers warranties.
      SHOULD THE COOLER BE INSTALLED BEFORE OR AFTER THE RADIATOR?
      • Hayden recommends installing the auxiliary cooler after the radiator to return the coolest fluid directly to the transmission. Installing the cooler before the radiator will still provide additional cooling and may be necessary in some difficult access applications.
      CAN YOU OVER COOL THE TRANSMISSION FLUID?
      • Transmissions are not highly sensitive to cool operating temperatures. However, in sub-zero (20-30° F) weather conditions transmission fluid can actually gel up in an external cooler and cease to flow, causing damage. Use of the radiator cooler actually helps warm the fluid under these conditions. It is critical in extreme cold conditions to use the original equipment cooler in series with the auxiliary cooler and allow the vehicle to warm up before driving.
      WHAT IS THE DIFFERENCE BETWEEN AN ULTRA-COOL® AND RAPID COOL® TRANS COOLERS?
      • Ultra Cool® is a tube and fin, (serpentine), design that is a time proven cost effective design. The round tube design is the strongest and most reliable cooler design but only gets cooling air on the forward facing side. The Rapid Cool® design is a plate and fin design similar to most radiator designs. The flat plates allow more contact with the cooling air. This provides a design that is about 1/3 more efficient size for size than comparable Ultra Cool® models.
    • REPEATED FAILURES OF NEW WATER PUMPS

      Multiple failures of new or rebuilt water pumps on the same vehicle when the failure appears to be bearing or seal related should perform the following:


      Closely inspect and replace the fan clutch if visible movement of the shaft in a vertical or horizontal direction is noted when checked by physically applying pressure to the fan blade in a front to back direction with the vehicle turned off and the battery disconnected. When the fan blade freely rotates when physically turned by hand while the vehicle is turned off with the battery disconnected. When the fan clutch shows signs of fluid leakage at the front thermal pin area located in the center front of the fan clutch or at the rear shaft and bearing area.

      REPEATED FAILURES OF NEW FAN CLUTCHES

      Multiple failures of new fan clutches on the same vehicle when the failure appears to be bearing, seal or shaft separation related should perform the following:


      • Closely inspect and replace the water pump if visible movement of the shaft in a vertical or horizontal direction is noted when checked by physically applying pressure to the fan blade in a front to back direction with the vehicle turned off and the battery disconnected.
      TRANSMISSION OIL AND FILTER CHANGE
      • When changing your transmission fluid and filter note the color of the fluid. If the fluid is brownish in color and smells like burnt toast the vehicle could be experiencing transmission overheating. Every 20 degrees Fahrenheit decrease in fluid temperature can double the life of the fluid and transmission components. Protect your vehicles transmission - install a Hayden Transmission Oil Cooler. The addition of a Hayden cooler can lower your transmissions temperature by up to 60 degrees Fahrenheit. Three times the amount required to double the life of your transmission.