Fan jammed, engine overheated - what to do now?

#1
So I recently did a 2" body lift and did the radiator drop relocation (AC kit) to ensure the radiator was in line with the fan and I could reattach the lower radiator shroud. Everything seemed to work well while driving pavement, but after a few hours of driving on a rough 4x4 road I guess the lower bushings slipped and the fan got jammed on the upper radiator shroud, preventing it from spinning...

I was slowly driving up a medium grade uphill when I noticed my temp gauge past High! Stopped the truck, put it in Park, turned the heat on max, and figured I'd let her run to cool off for a while. Checked the temp using my ODB2 reader at it was at 120c (250F). After 10min the truck wasn't cooling down at all, in fact it started making weird 'pressure' noises and then I saw coolant spill out. I then realized the fan was stuck and wasn't spinning! Shut er' down, waited a while, fixed the radiator bracket so the fan clears, started her back up and everything seemed fine. The coolant spill was just the coolant boiling over and spilled out of the overflow reservoir. All the hoses seemed fine.

I'm hoping I didn't do any permanent damage overheating it. I know you can blow head gaskets and such...

Wondering if there is anything I should do to mitigate? I topped up the coolant with bottled water on the trail right away. Should I replace the engine oil? Anything else? If the oil was burning I'm assuming it left a bunch of carbon on the engine - would a round of SeaFoam in the Crankcase be useful?
 

kootenay

Intergalacticsuperintndnt
#2
First issue you might have is warping the heads. Then cooked bearings. Hard to say, if you are truly concerned and like your truck I would take it to a professional mechanic or the Nissan dealer and have them check it out. Otherwise run it and see if there are any issues
 
#3
Replacing fluids now could cover any signs of cross-contamination, like coolant in your oil or vice-versa, which can help diagnose warped heads or blown gaskets without tearing down the engine. As Kootenay said, take it to a shop you trust or even the dealership to assess what might have been damaged before you try fixing things you're not sure you've broken.
 
#4
The auto parts stores sell an inexpensive kit that goes in place of the radiator cap and that has a chemical in it that changes color in the presence of exhaust gasses. It's used to see if there's any exhaust leakage in the head gaskets. I would start with that. Also keep a close eye out for water or coolant in the oil or oil in the radiator coolant. Biggest worry here isn't a blown gasket but a warped cylinder head. Aluminium heads react very badly when over heated! Coolant leaking into a cylinder and then trying to start the engine can, no WILL, cause hydrolocking and a broken piston or a broken rod, or worse. If you see ANY sign of the engine being locked up do NOT try to start it, take the spark plugs out and turn the engine over by hand and check for any signs of water in the cylinders. A knowledgeable mechanic can also pressure test each cylinder via the spark plug hole and tell you if the gasket is leaking. Connecting a vacuum gauge and watching it while driving can also spot pending problems.

llamalander is right, don't start "fixing" things at random. You'll just destroy any clues that a good mechanic could use to spot the real problems.
 
#5
Not sure which nissan you have. I have over heated my 3.3 in my 03 xterra more times than I care to admit. It is still running strong with no signs of any major damage. You will want to change the engine oil as excessive heat breaks down the oil. If you are concerned enough you can cut open your oil filter and check it for signs of metal. Im not going to say you didnt do any damage to the engine as it is always possible.
 
#6
I once blew a cylinder head gasket on a VW golf. You could smell the coolant,kinda like pancake syrup. I replaced the gasket and drove it another few years. Lucky for me no warped head or anything. When I saw the steam and the temp gauge climb I pulled over and shut it all down PDQ. If the engine wasn’t run for to long at high heat levels you might just get lucky.
 
#7
Don't panic. Engines get overheated all the time. Yes, things can go bad. But in general they do just fine.
Top off the coolant.
Mechanical or electric fan? Mechanical you may have smoked the clutch. If it runs warm at idle/low speeds now, put a clutch in. Electric may have popped the fuse.

Yes, the internet will tell you how to check everything and how to be worried that it is complete FUBAR. The real world is simply drive it and if something is bad, you will find it and fix it then.
 
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