How long to leave engine running safely without coolant on 2012 Yukon XL?

[smiley91]

There are a couple of unique aspects to this scenario that I think need to me mentioned: I recently purchased a 12' Yukon XL (with the 6.2L) with a known coolant leak. I am believing it to be the radiator, but could be the water pump. Since there have been delays in me diagnosing, the coolant reservoir has leaked out and is bone dry. I haven't turned it on for a week or two (and have been tackling other projects (replacing door handles, changing interior lights, etc) it drained the battery and I was too slow to put the battery charger on it. So, battery needs a jump, but I have no coolant. Would it be alright to turn the engine on long enough to jump battery, then turn back off, or would that be too much of a risk? Otherwise, I am thinking (when weather stays above 34°F) fill reservoir tank with some distilled water and coolant flush additive (previous owner used a green, non dex-cool mix that I want to get completely out of the system), drain the water/flush mix and fill/drain a few more times, then fill with distilled water once more, jump battery, and take to a buddy of mine (with a hydraulic lift) to properly diagnose, drain the water), replace the necessary parts, and put the proper coolant/water mixture in and drive it back home?

 

[Blackcar]

I would just replace battery first get that problem solved.
Then get fluid in system to find leak which shouldn't be hard sounds like its leaking without system coming up to pressure.

 

[Doubeleive]

There are a couple of unique aspects to this scenario that I think need to me mentioned: I recently purchased a 12' Yukon XL (with the 6.2L) with a known coolant leak. I am believing it to be the radiator, but could be the water pump. Since there have been delays in me diagnosing, the coolant reservoir has leaked out and is bone dry. I haven't turned it on for a week or two (and have been tackling other projects (replacing door handles, changing interior lights, etc) it drained the battery and I was too slow to put the battery charger on it. So, battery needs a jump, but I have no coolant. Would it be alright to turn the engine on long enough to jump battery, then turn back off, or would that be too much of a risk? Otherwise, I am thinking (when weather stays above 34°F) fill reservoir tank with some distilled water and coolant flush additive (previous owner used a green, non dex-cool mix that I want to get completely out of the system), drain the water/flush mix and fill/drain a few more times, then fill with distilled water once more, jump battery, and take to a buddy of mine (with a hydraulic lift) to properly diagnose, drain the water), replace the necessary parts, and put the proper coolant/water mixture in and drive it back home?

you would be fine to jump start it, but don't leave it running to re=charge the battery, you can put hose water it won't hurt anything it's going to get drained again anyway to fix whatever is leaking. btw the I have never used "distilled water" in any vehicle and drove them hundreds of thousands of miles with 50/50 mix
maybe if you ran it 100k with regular water coolant mix it might maybe possibly cause some rust particle or whatever, but most of use around here flush the coolant on a regular basis so....
if you put hose water in it and start it, keep the hose handy because after the water pump starts spinning and all the air bubble come out and the thermostat cycles it's going to need more depending on how low it was.

 

[Geotrash]

There are a couple of unique aspects to this scenario that I think need to me mentioned: I recently purchased a 12' Yukon XL (with the 6.2L) with a known coolant leak. I am believing it to be the radiator, but could be the water pump. Since there have been delays in me diagnosing, the coolant reservoir has leaked out and is bone dry. I haven't turned it on for a week or two (and have been tackling other projects (replacing door handles, changing interior lights, etc) it drained the battery and I was too slow to put the battery charger on it. So, battery needs a jump, but I have no coolant. Would it be alright to turn the engine on long enough to jump battery, then turn back off, or would that be too much of a risk? Otherwise, I am thinking (when weather stays above 34°F) fill reservoir tank with some distilled water and coolant flush additive (previous owner used a green, non dex-cool mix that I want to get completely out of the system), drain the water/flush mix and fill/drain a few more times, then fill with distilled water once more, jump battery, and take to a buddy of mine (with a hydraulic lift) to properly diagnose, drain the water), replace the necessary parts, and put the proper coolant/water mixture in and drive it back home?

There's no way to know for sure. Aluminum transfers heat much faster than cast iron and is also more susceptible to heat damage. If you had a cast iron block, running it for 30 seconds without coolant would be fine. But you don't so I personally would fill it with 50/50 Dexcool before I run it since you're in a cold climate. You can recover it when you drain the system at your buddy's shop to complete the work. or just replace it with new. Walmart sells premixed 50/50 Dexcool for $15/gallon. Worst case, you're out $45 in wasted coolant. Cheap insurance.

 

[Doubeleive]

btw distilled water freezes at the same temp as any tap water, the difference is when it is mixed with any amount of coolant and it's almost impossible to get all the coolant out even if it did have a leak