Coolant leaking when block plugged in

[mattgos]

My commute to work is very short, so I sometimes plug in the block to warm it up an hour or two before leaving in the fall/winter (I read on the TDR that it helps reduce the wear and tear of this type of duty cycle). I noticed a pool of fluid under my truck that was staining the asphalt (i. e. not pure water). I tracked where it was coming from and it looks like the coolant reservoir over-flow valve. The coolant reservoir is only half full.



Is this normal?



Anything I can do to stop the leak?



thx

mg

 

[AH64ID]

The 2006's are known to have a leak behind the turbo on the heater core return line, is there any way it's coming from there?

EDIT: I just remembered that many folks, including myself, have had the hose at the radiator cap leak. They don't have a clamp on them from the factory and after time they will drip as the coolant moves to/from the overflow.

 

[MLee]

Cold weather causes shrinkage----and some times you get drips---of coolant.

Check the hose clamps, if possible.

 

[mattgos]

Thanks guys, I will check the hose clamps. Any idea why plugging the block in causes it?

 

[rscurtis]

It raises the pressure in the cooling system even though the engine is not running. You may be able to find the leak with a pressure tester.

 

[mwilson]

Or just crawl under the truck before you start it in the morning. You should see the drip quite plainly then.



Any loose clamps or fittings will show up quickly on a cold morning after the truck has been plugged in.

I did not realize that the pressure caused it, alway figured it was the difference in temperature between the cold and hot components.



Block or frost plug heaters are not creating the heat that combustion does so you have warm water trying to move via convection in stone cold connections,



"""Hey that almost rhymes"""... ... .....



Big trucks do the same thing when plugged in during cold weather.



More severely than the CTD's as a rule because they are usually plugged in for at least all night, sometimes for an entire weekend at a time.



Mike.