yeah pull it out, and you take a malfunctioning t-stat out of the picture.

You'd have to run straight water for a long long time before it would kill a water pump, and straight water would do a lot more damage through corrosion than it would through lubrication...

as far as the compression issue have you done a leakdown test? that would pinpoint where the leak is in that cyl.

If the bearings are going out on the water pump it will still pump just fine till the bearings finally give (you'll know)

you're 100% sure it was burped right? flushed till the water ran clean? rad cap in good shape? have you tried pressure testing the cap, and rad?

O.K...I didn't think water could damage a water pump that easily.

Anyway, I am not 100% sure I burped it right. I never flushed it...I just filled it, then drained it with water a bunch of times. I have not tried testing the cap...and I don't know how to test either???

its a little pressure pump. probably worth just buying a new cap as they're like $5. If the cap isn't working right the coolant will boil at a lower temp causing overheating issues.

I dont think straight water would kill your pump.

Believe me, it will if run long enough.

I dont doubt it over the long run but we're talking about running straight water for a short period of time. Any way you go the water pump will wear out eventually anyway

*sigh* you're right...it'll wear out eventually anyway; like an engine...why bother changing your oil....it'll wear out eventually anyway.

I think I already addressed the short term use of straight water when the water vs. anti-freeze discussion started. I'll reiterate - short term running straight water is fine, long term you'll damage the pump not to mention corrode the radiator & cooling channels. The lubricant/anti-corrosion/anti-freeze/anti-boil benefits of antifreeze outweigh the superior cooling attributes of straight water. I do not know how long it'll take; but it will damage it. I have run straight water in plenty of vehicles over the years, mostly because I'm lazy & I'm here to tell you it doesn't take long to begin to cause damage. The corrosion is almost immediate because of the effect of water flowing over different metals; I forget the name of the process....galvanic response? I'm sure someone will know. Anyway it's just a matter of how much damage is acceptable to the individual.

its called galvanic corrosion/electrolosis. I'm just saying that i dont think he killed his pump by running straight water for a few weeks, and that that's not the result of the overheating issue, as some people implied it was.

I dont see how straight water would kill a water pump aside from corrosion. The bearings aren't lubricated by the water, and its a centrifugal pump. please explain since you seem to know so much about it...

O.K, I took the NEW thermostat out and drove around. It DID NOT overheat at all. It never reached its fully operating temp. It did go up...but it only went up to the line (cold side) and moved around there...but wasn't much. It did move once I started driving. So, what the hell is wrong? Do I need ANOTHER thermostat?

I HATE cooling issues SO much. Im not sure what it is, I can do suspension lifts, timing chains and all kinds of other stuff but cooling issues always just perplex me. If it's anything like mine the radiator might look fine but I'd pull it and have a rad. shop check it. Mine looks great from the top but is actually clogged as could be.

lol. Yeah...it's pretty damn new though. It was replaced due to the whole front end being smashed to hell by the previous owner...hopefully someone will shed some light no me though!

Get a thermometer (kitchen type) and a pot of water. Heat the pot of water with the t-stat in it, and make sure it opens at the right temp, 180-190 degrees fahrenheit, depending on the t-stat you have.

ps. dont do it when your wife's home...you'll never hear the end of it

An illustration for you



I'd like to also bring up a point about running with straight water. Looking at that pic, notice the bubbles forming at the bottom of the pan, and the temp of the water (this was near sea level BTW). Notice the bubbles form before the boiling pt of water! I contend the samething happens at your head cooling channels, although a higher temp because of the pressure in the system. You want your coolant to have as high a boiling pt as possible because when you have those bubbles forming on the head cooling channels you have less heat transfer to the coolant, kind of the opposite of what the Redline Water Wetter does. The antifreeze raises the boiling pt of the coolant. The higher you go in the mountains the lower your boiling pt and the worse this effect becomes. With my old 3.0 I found my coolant would sometimes boil after shut down (from heat soak) at elevations above about 11,000 ft. I also found my radiator cap wasn't holding the proper pressure because it the seal too old and cracked.

Oh, I see you have a 22re. Does turning off the heater make it run cooler by any chance? The 22re coolant flow dumps the flow from the heater core straight onto the thermostat (poor design if you ask me). In cold weather the flow from the heater core cools the coolant off so much it can close the t-stat. Toyota now makes a special 2 stage t-stat to solve that problem.

I don't think anyone implied it killed his pump. Only that it will eventually & the damage will begin immediately. You seem to be the only one who thought that.