Mazda Repair: MPV Water Pump, head gasket leak, bleeder valve

Question
My '98 MPV overheated. The bypass hose was blowing steam through a hole so I changed it, filled the radiator, and went on my merry way. It soon overheated again. I replaced the thermostat (Surprise! it's on the bottom hose!), but it overheated again. I filled the radiator again and pulled the top hose loose with the engine running. Lots of steam, but much water was pumping out.
I'm assuming there should be a significant amount of water pumping. So I'm guessing the water pump is out. Is this a bear of a job? Any hints?   
Thanks,
Mike

Answer
I will tell you this much, I send all my MPV timing belts, water pumps, and AC compressor related fixes to someone else. After years and years of doing them I have decided that this is the best fix for this car.

In this case I am preaching the doctrine of Lucinda Boltz.

First, check repair manual for location of air bleeder valve if present. Fill system, run system, bleed system, top off system, and see where that gets you. It sounds like it could be "air bound" which can cause a problem a lot like this.  

If it is STILL overheating "this is what I do and have done with all of my Nissan Quests and MPV's"

Sigh deeply
Call shop "another friend in my case"
Call wrecker
Wave goodbye
Car comes back in 2 days
Open wallet
Sigh Again
Consider myself lucky to have made it through with all of my knuckle skin intact.

Sometimes, the smartest thing to do is nothing and let someone else poke at it. It could very well have a slow leak or a head gasket leak that would do the same thing.
It could also need a new reservoir cap. These things cannot be tested unless you have the equipment to do so. So sometime you actually get out of it for less than you bargained for.

The repair manual "you should have one of these by now" details the endeavor you wish to undertake, some say it is simple, but they are usually not as picky as me or the people who I allow to work on my cars. Case in point the last two that came to me leaking antifreeze after only 500 miles due to poor surface preparation before installing the pump and or a mass of silicone the size of my fist!


Pay for it if you can, do it yourself if you have to.
Tell them it has a new thermostat. If it has not had a timing belt in the last 60K miles I would do that too since they will be in the aria. They may insist on it regardless of how old it is anyway.  

Regards,


John