This probably sounds like a huge noob question, but can I replace the thermostat w/o draining the radiator and w/o making a big mess?

I bought two thermostats from Mazda and they looked nothing like the original one with the little pingle thingy on it, but Mazda convinced me it just was a different vendor. Niether of the two thermostats worked and I'm tired of draining the radiator and wondered if I could save time by just disconnecting the upper hose at the engine outlet.

 

You could probably open the top drain plug and drain that out into a bucket, then take off the thermo cover and not have too much spillage. Just have a thick absorbant towel around it.

 

I dont see a problem with just taking off the upper hose and the tstat cover. Thats what I did.

 

I have done this a few times. When I did it on my TII was pull the overflow line from the tank and put it into a clean gallon jug and pop the radiator cap and then put your hand over where the cap normally sits and then squeeze the radiator hose. The radiator hose has to be in good condition to make it into a hand pump and the overflow line needs to be clean and free of dirt. Use collant from jug to fill the system back up with when finished.

 

That's a good idea. I was gonna siphon some but your way seems better. My hose is new so there should be no problem it becoming a hand pump. Thanks