Hey guys! So last night I drove my D2 from my house to the beach (about 4-5 miles away), and it did perfectly just as usual. But on my way back from the beach, while I was stopped at a short traffic light, with no signs what so ever, my thermostat suddenly and quickly bagan to rise, and it rose all the way up to the red line as high as it could possibly go, in a matter of seconds. Since I was in an intersection, I couldn't pull off into the grass, so I got off and pulled over into the nearest parking lot as soon as I could. I turned my rover off and opened the hood. I immediately recognized that the coolant was spilling and boiling up out of the coolant tank, which has happened before, but I had sealed it up as a band-aid until the new tank that I had ordered arrived. Thankfully it had. But it was at home. So I started my rover back up and the thermostat was about at regular tempature again. So I crossed my fingers and hoped that I would make it home, and I did. (I know, doing so was a HUGE risk). But this morning I put in the new coolant tank, started up my rover and drove it around for awhile, and it was at its normal level and the thermostat never rose. There's no leak anymore. I know this probably a simple question, but just to be sure, do you think it's safe to drive? I have work tomorrow and I don't want to take the risk of blowing my engine in case it does run hot, so I'm just taking precautions. A broken coolant tank is common, but the fact that it got so hot and happened so fast with no warning has me a little nervous that it could have been something else that might show itself at a bad time.

 

I would not drive you truck. You need to find the issue before you kill your engine. I would do a pressure test to see if you are holding pressure. I would look to see if anything is leaking. Check your oil to see if it is milky, i.e. coolant in the oil. Pull your spark plugs too see if you have coolant inside the cylinders. Then do a chem test to see if you have a cracked block. Check/replace your thermostat, flush your coolant system.

 

Thanks. I checked everything and there's no coolant anywhere except for in the coolant tank. The thermostat is still back down at its normal stance, and there are no signs or smells of anything leaking or excessive heat coming from under the hood. Everything seems normal. My best guess is that it's all what I thought it was; a cracked coolant tank. The crack likely made the pressure drop and caused it to overheat. And the fact that the coolant was leaking out surely contributed as well.

 

Well once you get the new coolant tank in I would still run the pressure test as well as the chem test. You did overheat your engine pretty good. I would also consider changing your thermostat to the grey bodies 180 degree to help you keep it running a little cooler. Good luck.

 

A couple things:

1) what was wrong with the old tank? If it was cracked before the overheat and you already knew it, then it was most likely the only cause of your overheat and it should be good to go.

2) As the member above mentioned, I would install the genuine grey LR 180 soft spring ($80) thermostat as it will bring your engine temps down to around 186.

3) Buy an UltraGauge! UltraGauge OBDII Scan tool & Information Center Your temps may look fine on the gauge on the dash but it could still be running hot. The Gauge on the dash does not move from the middle until it is around 230 I believe. That is way to hot already and by the time you notice it's in the red your engine is very close to being cooked. If the ultragauge shows you running in between 204-212 with a stock thermostat then you are good to drive the truck. If you are any higher then I would park the truck until you find the problem.

4) Did you bleed the cooling system after installing the new cooling tank and overheating?