well not sure if this is just good luck or what, but we had a 91 montero that we didn't even change the air filter in until it 125k miles on it...............then after it proved itself my dad finally got t-belt water pump and everything else done on it......drove it another 100k miles and then my brother smashed it into a deer.

anyway, that water pump lasted 125k miles.

I will keep my eye on it, but it just doesn't make sense to me to tear it down all the way to the water pump with a t-belt that only has 20k on it just b/c the pump could go bad.

the problem seems to be solved with the cooling system though. they disconnected heater core at fire wall and power flushed it strong both ways with a heavy duty cleaner, no gushing sound now.

I suppose b/c of the restriction in the heater core, that is where the noice was coming from in addition to more air being trapped b/c of the restrictions. hopefully it will behave itself now. I will keep a more watchful eye on the over flow bottle and if i see it starting to get sediment on the bottom again, it will get another power flush; hopefully most of it is out and that won't happen to me again.

thanks again to all who gave such good input.

on a lighter note, I will be installing a hot water heat exchanger on my 97SR to have hot water when camping...........can anyone confirm if the gen II setup has a valve inline with the heater core hoses or is it a continuous flow system that has a baffle on the air duct instead? that little tid bit of info will dictate how I install the hot water heat exchanger (series or parrelel) with the heater core.