Losing Coolant & Water Rapidly

[zero_one]

I just got my car which i absolutely love and have had no problems until today. i came home from my girlfriends place and noticed a bit of smoke coming from the hood and checked it out. coolant levels were full and there was water still in the rad. i went downtown and back (10km at best) and on my way home the car over heated (red lined). NO water and the coolant reservoir was empty. doesn't look like anything is coming from the engine and i cant see a leak in the rad. Any Ideas? Its a 94 with the DOHC 24 Valve 1.8L V6. This is the first car i have owned outside of a Honda or a Volkswagon. I was reading around the forum and saw that it could be issues with the head gasket or cylinder head, as i had noticed the exhaust was milky white (however the oil is fine). what would roughly be the cost of this work if i take it to a shop? If this is indeed the the cause would driving through a large puddle (1 ft - 1.5 ft deep) being as cold as it is out possibly be a cause?

Thanx for any input.

[Ryan]

I'd fill it with water and run it, and try and hunt down the leak. If you lost it all that fast, its not headgaskets or anything else. It will be a burst hose, bad waterpump, or a hole/crack in the rad.

Depending on how long you ran it hot, you might need the gaskets anyway...

[wytbishop]

If there is no leak in th eengine or the rad, it is usually the head gasket. It's not that it's being burned, but compression is leaking from the cylinder into the coolant jacket and pressurizing the cooling system which forces the coolant out and overflows the reservoir. it is also possible that the water pump is sucking air and pumping it into the system.

I have seen both of these cases in the past. Fill the system and run it until you see something happen. My guess is after it warms up you'll see coolant flowing out from the rad cap overflow into the surge tank and overflowing from there. If it's not being burned and there's no obvious leak it has to be one of the things I listed.

[zero_one]

if it is the case that that it turns out to be the head gasket, how much should i be expecting to have it replaced.

[wytbishop]

If it is a head gasket it's likely only one. If they can isolate which one...I'd say 4 hours plus materials...$600 at a dealership, $400 at an independant, $150 if you can do it yourself.

It's not rocket science and you could do it with hand tools.

If it's a water pump...depends on how many pain in the butt issues you encounter. I could do it in 4 hours but one guy on here took daysa nd had lots of trouble with various issues. A good mechanic it would be similar in cost to changing a head gasket...ish.