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Subject: Diagnosing overheating

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Tom    Posted 02-18-2018 at 20:35:54 [URL] [DELETE]        [Reply] [No Email]  
  • Diagnosing overheating
  • I have a 601 that's overheating after about 15 minutes of running. Can someone tell me what order I should address the problem in? I flushed the radiator and that had no effect.

    36 coupe    Posted 02-21-2018 at 08:33:04 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Diagnosing overheating
  • Test the thermostat on the stove in a tuna can full of water,A meat thermometer will check opening temp.

    Tim Daley(MI)    Posted 02-19-2018 at 06:26:14 [URL] [DELETE]        [Reply] [No Email]  
  • Re: Diagnosing overheating
  • Like Bruce(VA) says, overheating is the #1 cause of overheating. Low coolant/under filling is #2. Don't fill radiator all the way to the top. Are you using a thermostat? Flushing the radiator may not be enough especially if it is the original one. It may be time to pull it and have a reliable radiator shop boil it clean, repair/solder any pinholes, and straighten the fins.

    Tim Daley(MI)

    Bruce (VA)    Posted 02-18-2018 at 21:02:11 [URL] [DELETE]        [Reply] [Email]  
  • Re: Diagnosing overheating
  • The most common reason for it to ďover heatĒ is over filling the radiator. Only add enough fluid to cover the core. (check out tip # 24, below as well as tips 25 & 35) It is not actually over heating; it is just spewing out the excess water.

    If the radiator is not overfilled, check for low coolant, a loose fan belt, debris in the radiator fins or a stuck thermostat. A bad water pump will usually squeak or leak. (If you ever have a water pump start leaking or making noise, replace it immediately. A water pump will come apart & launch the fan into the radiator.) And, unless you have a new/rebuilt water pump from a reputable source, it could have impeller erosion. The pump will turn, it wonít leak, but it isnít circulating water.

    The fan belt should have 1/2" of flex at the mid-point; no more, no less.

    Unless you have a pusher fan, blowing out the radiator from the engine side is always a good idea.

    If none of that works, you may need to flush the radiator & block.

    Get a can/bottle of cleaner from the parts store.

    Remove the t-stat. Reconnect the hose.

    Pour the cleaner in the radiator & run the tractor to operating temp.

    Then, remove the bottom hose from the radiator, stuff a rag in the bottom radiator hose connection, & stick your garden hose in the top of the radiator. Turn the water on (reverse flush) & the water will flow into the radiator, then the block & out of the disconnected lower hose. Let it run until the water is clear. Then, check the radiator flow. Stick the hose in the top of the radiator; the water should flow out of the bottom w/o backing up in the filler neck. It should flow at 19.5 gallons a minute. Donít forget to put the t-stat back in correctly!

    Use 50/50 anti-freeze & distilled water as your coolant. The anti-freeze contains rust inhibitors, pump lubricant & raises the boiling point of the coolant.

    If you do need to get the radiator re-cored, make sure you get the flat fin industrial core. Automotive style cores will clog up w/ debris very quickly.

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