Glow plugs in GC2300

   / Glow plugs in GC2300 #1  

DEWFPO

Veteran Member
Joined
Jun 2, 2007
Messages
1,100
Location
"Up High in the Rockies"
Tractor
2009 Bobcat Toolcat 5600 D
Now that winter is here again (11F last night), the GC2300 is getting harder and harder to start again. I run the glow plugs for 10-15 seconds, turn the key to pump fuel for another 5-7 seconds, and it cranks for 4-5 seconds at a minimum, smokes white as it cranks, then it lights. Once warm, it starts on the first crank, every time no problem. I've have checked for power to the glow plugs and they get full battery voltage when the switch is on glow plugs. I'm using 5% biodiesel with an additive to help prevent gelling and is also a Cetane modifier as well.

Even at 55F, it is slower to start. The colder it gets, the more cranking it takes to start. If I use the bock heater it starts faster.

Is it possible the glow plugs are getting voltage but not getting hot enough? The 2300 is a 2006 with 51 hrs on it. I snowblow all winter and keep it in an unheated garage.

The battery is charged up full and at 50 hrs I switched to Amsoil 5w30 HDD diesel oil. (note : no difference in cold starting after the oil change).

Any thoughts or tips are appreciated. This is my first diesel and I'm still on the learning curve.

DEWFPO
 
   / Glow plugs in GC2300 #2  
You really need to check the resistance on those plugs. My guess would be you have one bad one. If I remember correctly the reading should be slightly under 1 ohm if the plug is good.....Maybe .9? Someone correct me if I'm wrong. If you have a bus bar be sure to take it off for the check.
 
   / Glow plugs in GC2300 #3  
Assuming the battery has been tested, and you check the resistance on the glow plugs, here is some advice from my experiences:
Pull the glow plugs and see if by chance they are carboned up, this can insulate them and keep them from being effective. A dead give away that this is the case is unscrew them and if they won't pull out it is because of the deposits on them. Keep working them untill they come out, clean them and reinstall them
Then, have you tried leaving them on for a very long time 30 sec or more, when it is cold? Some engines this can help, I have a 92 Mittsubishi that takes long preheats. Although my 2310 starts up with 15 sec. even when its really cold.
The next thing it could be then is one or more injectors are clogged, I was told by an old diesel mechanic that putting 1/2 quart of ATF in 5 gal. of diesel will clean the injectors better than anything. My father has tried this in his old Honda and it helped some. His tractor starts fine and runs great all summer as soon as it gets cooler in the fall it takes longer to fire and smokes for the first few min. this gets worse as it gets colder, and goes away when summer returns. Our research on the web has found all the tractors like his do this, and the cure seems to be replacing the very expensive injectors.
All these are problems you should not be having with a 51 hr. tractor. Makes me wonder about the Biodiesel being involved?
Hopefully its just one bad glow plug.
 
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   / Glow plugs in GC2300 #4  
Your tractor is still under warranty? I would call the dealer. Chances are you have a bad glow plug or maybe all bad. It is pretty easy to test them, but if it is under warranty why mess with it. Thats why you get a warranty.
I am interested in what effects the bio-diesel has had on the inside of the motor though. I wonder if it is carbon build up? That would be something on a relatively new tractor.
 
   / Glow plugs in GC2300
  • Thread Starter
#5  
Thanks for all the input, I appreciate it.

I checked the resistance on the glow plugs and they are are 0.8 ohms (the DVOM ranges from 0.9-0.7). The battery is at full charge and the glow plugs are getting close to battery voltage when the circuit is energized. I may pull one of the glow plugs to see if they are carboned up.

I live at 7,200 elev. but that shouldn't matter. The tractor started faster when I first got it. The MF dealer is 240 miles away round trip so it's not very convenient to bring it in. I'd have to leave it and come back, 480 miles total and I'd have to borrow a trailer.

I'll pick up some fresh fuel tomorrow, put the additive in at 1 oz per gallon and see how she does.

Again, thanks.

DEWFPO
 
   / Glow plugs in GC2300 #6  
Pull all 4 glow plugs to make sure it is not 1 cylinder causing your problem. It will not take long.
 
   / Glow plugs in GC2300
  • Thread Starter
#7  
Picked up some fresh #1 off-road diesel today, we'll see if that makes a difference.

DEWFPO
 
   / Glow plugs in GC2300 #8  
After I changed my oil to Rotella synthetic it made quite a difference in winter starting of my GC2300.
 
 
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