My water pump decided it didn't want to hold in the coolant anymore. so I bought a rebuilt one and put it on, changed all the hoses and belts while I was at it. Now, no matter what , my car is running 20 to 25 degrees hotter than it used. I am running 75-25% mix water and anti-freeze respectively. the same mix I had before. what gives?

 

Be sure to check your lower suction hose that it has the internal wires to keep it from collapsing. Under boost, this really caused my temps to rise.

 

Interesting... What are the exact temps you're running

 

What condition is your radiator in? Is it new? If not, how old is it? Have you ever had it rodded out? Did you replace your thermostat as well? How old is the motor? Coolant o-rings..... I'm sure you know your cooling system acts as one.

 

The one that sneaks up on you is the fan clutch.
When the engine is hot, it should pull hard up to 4K, then stay at 4K as the engine revs higher.
If it's slipping at 2500 - it's bad.

 

I did not replace my thermostat because I did this very recently. The radiator is not new, but I do clean it front to back frequently. It is the stock aluminum core. What is "rodded out"? The motor has 150k on the clock. the oil seals are a little under the weather, but the water seals are fine as far as I can tell. It doesn't use any coolant since the change.
I don't think any of my 7s (5) have that spring in the lower hose. I asumed it never needed it. I have always known why they exisited and thought it was weird that the cars didn't have one, but I never have come accross one. This is an n/a also.
I am running an electirc fan that comes on when the ignition is on. this is because I live and drive in Memphis traffic. Hot and humid enough to swim to down the street. the other day humidity was 98%! Two more degrees and Memphis would have been under water. Something should be done! I'm going to right The Mator! What am I saying that idiot can't even direct traffic. Longest time in office for Memphis. Pfft! No one likes him but he keeps coming back like roaches do.
UUhh? Hi. me again.
Other than the new hoses, the new belts, and the new water pump, there have been no other changes save gasoline.
This hasn't red lined yet. but I see the temp clime when I am driving hard. So I back down. To my know ledge, this car has only high temped once in its life. and I caused that. Up until now the temperature was very predictable.

 

That stat you replaced a while back, is it aftermarket or OEM?

 

Did you inspect the water pump housing? If it was pitted it needs to be replaced

 

housing is fine.
stat is aftermarket.

 

housing is fine.
stat is aftermarket.

 

What temp are you running @ normally and when it rises?

 

get rid of that aftermarket stat and go get a MAZDA one. don't ask why, i don't know, but for me the aftermarket stats would fail all the time. clean the pulleys for the belts so they don't slip.

"rodding" out the radiato is when they take it apart and clean the core. It's not a bad idea at all if you have as many miles as you do. you'll really notice the temp drop. I'm in Columbus MS about 2 hrs south, if you want to go to Tupelo MS maybe we can meet up?

 

There is a couple of reasons to use the Mazda stat instead of an aftermarket one:

1. Your car might run hotter with the aftermarket stat. My car ran a whole 1/4 of the guage higher when I switched to a stant. (I even remember picking the lower temp model when I bought it). And then when I finally switched back to Mazda, my temp guage read lower again. That was all it took for me to always make sure and use the Mazda one.

2. Many have said that the Mazda one is of better quality than the Stant variety, and it is capable of responding to temp changes quicker. Also, when I looked at mine, it seemed to me that it would have been able to allow more flow, but that is just speculation.

 

but I still didn't change the stat when I changed the water pump. I only changed the water pump, the belts and the hoses.
I'm giving up. I'll take it to some one.

 

I bet the problem is with the waterpump. The clearance between the impeller blades and the housing is not tight enough, and the water isn't circulating like it should.

 

From what I have gathered at my time here on the forum and with dealing with RX-7s, is that you always want to use the OEM oil filters, radiator pressure caps, and thermostats.