Engine block heater malfunction on TC33D

   / Engine block heater malfunction on TC33D #31  
I bet you'll find the heating element open to the coolant, same way as a water heater will burn out. I may have missed it but did you check for continuity from either one of the actual heaters pins to the chassis of the tractor?
 
   / Engine block heater malfunction on TC33D #32  
As a stopgap till warmer weather a tarp And small heater will work well.
 
   / Engine block heater malfunction on TC33D #33  
Strange results from my testing:

Anytime I plug in the heater, it trips the GFI. I tried plugging in to another GFI circuit, and it does the same thing.

The replacement heater and cord came in today. Hoping it was just the cord, I plugged the new cord into the old heater on the engine. Same results: tripped the GFI.

Just as a test, I plugged the new cord and the new heater (not mounted on the tractor) in to the outlet. The heater operated normally.

These tests indicate a problem with the heater itself. Out of curiosity, I checked the resistance of the new heater, and compared it to the old. I could not measure any significant difference. It's odd. I expected to be able to see some difference that would cause the GFI to trip. It was a cheap Harbor Freight ohmmeter, so maybe it was not sensitive enough. Or maybe the few volts put out by the ohmmeter are not making it through like the 110VAC would.

So I guess replacing the block heater is in my future. I had hoped not to have to drain the coolant (I have no heated work space for this).
GFCI circuits determine leakage current by comparing the outbound current on the black (phase) line to the return current coming back on the neutral. Any difference measured is assumed to be caused by a leakage path to ground.

Here's the rub..leakage can be between the phase run OR the neutral run and ground.

It's not always easy to see with a standard ohm meter (a megger is best) but you might be able to see a notable difference in resistance between ground and each line (phase and neutral).

As many others have said, corrosion is a likely root cause, you've done enough research to indicate the location is internal to the heater body, not the cable.
 
   / Engine block heater malfunction on TC33D #34  
GFCI is out of my area of expertise (totally). I did have a problem with new breakers in my panel that had the word "arc" in their name... constant tripping before I replaced them with standard breakers. Anyway, my lack of GFCI knowledge is totally unrelated...

You don't mention if you had the new heater submerged in water during your test. Testing a heating element in open air can easily damage them, as well as catastrophically self destruct.
 
   / Engine block heater malfunction on TC33D
  • Thread Starter
#35  
You don't mention if you had the new heater submerged in water during your test. Testing a heating element in open air can easily damage them, as well as catastrophically self destruct.
Well, hopefully I haven't fried it. It was not submerged. I was concerned about it overheating, so only plugged it in for a few seconds.

I guess I should submerge it and plug it in again to make sure it works before installing in the tractor.
 
   / Engine block heater malfunction on TC33D #36  
How about an omh test between an individual heater terminal to the case or block on the installed one.

Looking for a heater short internally.
 
   / Engine block heater malfunction on TC33D #37  
You may need to do a megger test to get a result for that gfci
 
   / Engine block heater malfunction on TC33D
  • Thread Starter
#38  
Finally getting around to draining the coolant so I can replace the heater plug.

I've somehow lost track of what coolant/antifreeze I've been using. Is it just the standard green antifreeze or does it use something special? The owner's manual is no help. It just says 50/50 mix and capacity is 4.2 quarts. I'm gussing that the lack of any specific warning on the owner's manual means it's not too picky.
 
   / Engine block heater malfunction on TC33D #39  
Finally getting around to draining the coolant so I can replace the heater plug.

I've somehow lost track of what coolant/antifreeze I've been using. Is it just the standard green antifreeze or does it use something special? The owner's manual is no help. It just says 50/50 mix and capacity is 4.2 quarts. I'm gussing that the lack of any specific warning on the owner's manual means it's not too picky.
In today's market you can buy a variety of Antifreeze. I use this. It doesn't matter what's been previously used and will mix with any type.

You can buy this full strength or pre mixed. I never buy pre mixed, what a ripoff. I can figure out how to add equal parts of water/antifreeze. :)



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   / Engine block heater malfunction on TC33D #40  
The latest issue with my TC33D: the engine block heater now trips the GFI outlet in my garage any time I plug it in. I have not yet even looked to see where this is on the engine. I'm hoping it's not a big deal to get to. As far as I know, this was a factory installed item (could have been a dealer installed accessory, but I think they get all of the tractors they order this way).

Time to start poking through the parts and service manuals to see what I can find. If anyone has messed with one of these and has any good tips on what to look for, please pass them along.
Just a thought. Otherwise sometimes GFCI outlets do actually wear out and become too sensitive.

 
 
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