4120 coolant leak

   / 4120 coolant leak #1  

Jkline

Member
Joined
Feb 19, 2005
Messages
25
I can't find the source. If the tractor sits, it does not leak; if it sits with power to the glow plug, I might have 4 or 5 tablespoons of fluid on the shop floor. When the engine is running it doesn't seem to be leaking, but can't tell for sure, but given the fluid drop in the overflow res, it must be.

Hope this is enough info for some ideas as to cause and fix. Hoping it isn't the dreaded timing belt cover leak.

I'll tackle car and truck repair, but I've never had to do any work on this tractor, so it is a bit intimidating.

2004, 450 hours.

Thanks
 
   / 4120 coolant leak #2  
What is "fluid"?... Diesel, motor oil, hydraulic or coolant?....

Have you tried looking at "things" directly above puddle?

Dale
 
   / 4120 coolant leak
  • Thread Starter
#3  
What is "fluid"?... Diesel, motor oil, hydraulic or coolant?....

Have you tried looking at "things" directly above puddle?

Dale

Before getting so uppity and condescending, you could try reading the title, capiche?

Looking up from the puddle tells one nothing, because it runs down the side of the engine, you know gravity, and drops off from the lowest point. There is coolant on both sides of the engine, probably because of the fan.

What I'm trying to ascertain, is that if the glow plug is plugged in, and working, and coolant is leaking, is that symptomatic of anything?
 
   / 4120 coolant leak
  • Thread Starter
#5  
@Bill-- yes, I suppose so.
 
   / 4120 coolant leak #6  
I am not sure how you turn a glow plug on with out turning the key.
So if you turn the key have someone look for the leak while you turn the key.
 
   / 4120 coolant leak
  • Thread Starter
#7  
You guys will need to cut me some slack, as I don't know the proper names for many parts on the tractor.

When I plug in the tractor-- turning on the block heater-- I will find small puddle of antifreeze on the shop floor the next day. If the block heater is not plugged in, there will be no fluid on the floor.

Forget I said glow plug.

Thanks,
 
Last edited:
   / 4120 coolant leak #8  
I am not sure how you turn a glow plug on with out turning the key.
So if you turn the key have someone look for the leak while you turn the key.

He's saying glow plug, but he means block heater.
(nevermind ;) )
 
   / 4120 coolant leak #9  
The block heater should not cause any sort of leak. It should only be warming the coolant up about 60 or 70 degrees above the ambient temperature.
If plugging in the block heater causes it to leak, I’d say it must be the block heater itself.
I think you will have to clean up the engine, then plug in the heater and check it every 30 minutes to see exactly where the coolant is coming from.
 
   / 4120 coolant leak #10  
JK first cold snap this winter one morning I started the tractor and left the block heater plugged in when I unplugged it there was a small puddle of antifreeze under the tractor.I traced it to the block heater unscrewed the cord from the heating element and found that's where it was leaking very little from around 1 of the elements. Dried it up put it back together and have unplugged it before starting the tractor and not had it leak since approx. 6 wks. ago. As for the fluid in your overflow tank if it keeps going down a bit with no sign of leaks leave it a bit low you may find that where it stays . Why it leaked plugged in when the motor was running I have no idea but won't hurt for you to give it a try.
 

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