Howdy all, would love some help trouble shooting.

Just finished a HG replacement job on 2000 Disco II. Everything started up and seems to run fine. Did multiple tests in the driveway getting the engine up to operating temp and letting it run for a while. No overheating, no leaks, heater blows hot. Drove it around the block a couple times and no problems.

Took it for an actual test drive. Immediately heard some minor bubbles, but figured it was air and I need to bleed it. Temp seems fine so decided to take it up a local semi steep grade. Immediately starts overheating and gushing coolant. Pull over right away, but can't tell where the coolant is coming from because it is sprayed everywhere and everything is wet. Saw white smoke behind me as I pulled over, but couldn't tell if it was from the engine bay or exhaust.

I limped it home by topping up coolant and letting it cool down all the way. Now the heater blows cold even when the temp gets to normal.

Get it home and in my driveway and the next day I let it get up to operating temp. Heater blows ice cold, but truck doesn't overheat, no matter how long I let it idle. White smoke from exhaust, but don't how to tell if that is from a leak or because it's 30 degrees outside. There is a pretty decent sized puddle under the exhaust too, it seems like more than what condensation would do.

The only leaking is from the overflow tube on the reservoir. So there seems to be blockage. Tstat was replaced prob about 10k ago and worked fine before HG job.

What should my next step be? Should I buy an exhaust gas leak test? I can turn bolts and follow instructions, but I am a horrible trouble shooter! Thanks for your help.

 

I would find out where the coolant is gushing from first fix that then top it off with a good bleed then retest

 

Andrew,
When you put it back together did you have the heads inspected and shaved, did you use new head bolts and use the proper torque spec?

 

Did you make sure that you had a clean work area? Clean block real good before putting it back together. Heater core may have blockage that you jarred up when you did the gaskets. Try back flushing the core after you find your leak.

 

Yes on the heads inspected and decked, proper torques, new head bolts. Clean work area? I'm far from a clean and organized mechanic, so this is a possibility.

I think I'm going to take it in since it is now winter and don't want to be flushing and finding leaks in my garage.

 

To save making a mess, do a coolant pressure test first and if needed, a chemical block test to check for exhaust.