overheating and a radiator flush...kind of

[notarobot]

Hi. I'm new to the forum and to owning an 02' Pt Cruiser (standard, no frills, not even cruise control!).

Anyway, to get to the point, the car started overheating a few days ago. I checked the radiator fluid and found that it was very very low. I also heard and could feel a lot of gurgling/bubbling as it overheats and also when the car was being parked and turned off.

I think the radiator fan is fine as I can hear it with the AC on high. I replaced the radiator cap today as the old one had a great deal of wear on the seal. I haven't had a (keeping my fingers crossed) problem since replacing it. (I still hear a slight grumbling when parking the car however, though I don't see that there is any leaking beneath the car so I think that there might be air in the coolant system.)

If after a few days, the car no longer overheats or shows signs of significant leakage I plan on replacing what is now mostly water in my coolant system with HOAT coolant. However, I have a problem!

Just before my cross country drive, I filled my radiator with non-HOAT antifreeze, not knowing then what I know now. I don't think I used Dex-cool however, but I don't really know. I know I need to flush the radiator before I pour in the HOAT coolant but I can't afford to have the radiator professionally flushed right now as everyone is charging around $100.

I would like to flush it myself with a kit but don't know if I have access to a garden hose as I live in an apartment complex, (though if finding a garden hose is my only viable choice then I will.)

Although, because it was very low and as I've been forced to refill it with water a few times, the liquid that is in my radiator seems mostly to be water now, as it runs fairly clear with the radiator cap off.
Someone at Napa suggested that, if it was the case that most of my coolant had already leaked out, I could try three or so cycles of draining the radiator, refilling it with water, closing everything up and then running it for a few minutes, and finally draining it off again. After the last drain/refill cycle, the coolant system might then be 'clean' enough to handle the HOAT coolant again.

Is this just wishful thinking?

[Dino]

If it's clear now it must be mostly water, do what the Napa guy suggested and it should be fine. You don't want to run around on just water for that long.

[cjb15]

If your current fluid is pretty clear and not rusty and you do not have an overheating issue anymore, you probably would be OK flushing out the radiator and refilling it. A DYI radiator flush typically leaves water/coolant in the engine so you have to put undiluted coolant in to get the correct mix.
You can buy a little tester at the auto parts store.
You do need coolant/antifreeze in the summer especially if you use your A/C because it gives you a higher boiling point.
Make sure you bleed the air out via the bleeder next to the thermostat.
Lastly keep an eye on your coolant level. Unless you have a leak the level should not go down. There is a nifty pressure tester that most mechanics have that pressurizes the system when cold and finds the leaks. It is also probably cheap enough for a DIYer.

[notarobot]

Thanks!
The car is still overheating, though not as often or as quickly as it did before...so I'm hoping that its just air in the system that is causing it. Would have drained the radiator today but I can't find the cursed drainplug...

[Dino]

Originally Posted by notarobot

Thanks!
The car is still overheating, though not as often or as quickly as it did before...so I'm hoping that its just air in the system that is causing it. Would have drained the radiator today but I can't find the cursed drainplug...

Just pull off the lower hose if you can't find the plug