3720 (2009) Glow Plug Timing

   / 3720 (2009) Glow Plug Timing #1  

9973720wb19

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This is my first tractor and I have a question about the length of time one should pre-heat the glow plug. The manual says 10-15 seconds, however the dashboard readout always shows "Wait" longer than the recomended seconds in the manual. Should I wait until the "Wait" light goes off? I've been just preheating for 10-15 secs. and it starts right up.

Thanks
 
   / 3720 (2009) Glow Plug Timing #3  
I don't think that light will ever go out, as long as you manually hold it on. Don't think in the coldest of temp, I've ever held it on for more than 5-8 seconds. Always starts, and sometimes smokes a bit for short time. That is the 11 yr old Deere 4300 with Yanmar 3cyl. 600 hours
 
   / 3720 (2009) Glow Plug Timing #4  
I don't think your 3720 has glow plugs it is a direct injection engine and has air preheater in the airbox, and that is what you are doing when holding in key running the preheater.
I am not sure of this but I think that is the way it is set up.
 
   / 3720 (2009) Glow Plug Timing #5  
I don't have a 3720 either, but I don't believe there are glowplugs on a turbocharged intercooler diesel. Should start very easily, even in the cold.
 
   / 3720 (2009) Glow Plug Timing #6  
My 2006 3320 has no glow plugs, only a manifold heater. Unless they changed something in later years the 3720 won't have them either.

I press the key in and the heater and the dash light turn on. The light stays on until you release the key. 10 seconds is plenty long enough for me.
 
   / 3720 (2009) Glow Plug Timing #7  
When the temperature is below 35 deg, I hold the key in for about 5 to 8 seconds on my 2007 3720 and it starts immediately. It does not have an engine block/coolant heater.
 
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   / 3720 (2009) Glow Plug Timing
  • Thread Starter
#8  
thanks guys. I checked the manual and my 2009 3720 with 60 hours DOES NOT HAVE GLOW PLUS...it says press the key for 10 to 30 secs to activate the intake air heater system. thanks for your help.
 
   / 3720 (2009) Glow Plug Timing #9  
When the temperature is below 35 deg, I hold the key in for about 5 to 8 seconds on my 2007 3720 and it starts immediately. It does not have an engine block/coolant heater.

Same here, below 20 deg, starts right up.
 
   / 3720 (2009) Glow Plug Timing #10  
I seldom use my preheat. If it fails to start then I give it a few seconds of heat. It generally pops off cleanly after about 2 cylinders come over center.
 
 
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