A few months ago, I put a new aluminum koyo radiator on my car. I installed it, and for awhile it was leaking coolant past the hose clamps. I fixed that up, and now I'm at the point where I'm not even getting drips, but I start the car and the stock temperature gauge climbs to H without stopping until I shut the car down before it gets too hot. I'm running it at idle with me revving it occasionally. After I shut the car down and investigate under the hood I hear what sounds like boiling coolant hissing in the coolant filler pipe under the cap.
As a side note, I have the plastic undertray off right now.
I have a few things I think it might be..
It could be the thermostat, what prompted me to get the new radiator was a pretty bad overheating that luckily didn't damage the car, but I don't know if the extreme temperatures damaged the wax or whatever in the thermostat.
Another possibility is that coolant isn't flowing because I have a 50-50 mix of coolant and water and the water in my coolant pipe is clear with no green in it.
I searched the boards but couldn't find any relevant info.
I'm pretty familiar with my car, but I'm not that familiar with cooling issues so if anyone knowledgeable has any suggestions I would greatly appreciate it.
If you need more info about things, please ask me.
I have spring break this week with lots of time to repair the car and I want to get my it running again so i can smog it and get it going for summer.

Thanks, TW

 

It sounds like a stuck thermostat to me.

 

I guess I'm heading down to the mazda dealer monday then, haha

 

It was the thermostat. Many thanks to polito.
I was able to get it on the road again, and I was able to install my new intake as a bonus.
Now hopefully I pass the smog and I'll be good to go.

 

youre welcome!! glad you got it running

 

Went to rusty's today to get my smog check.

Results:
Emissions: PASS, running VERY clean.
Visual: PASS
Functional: EGR broken, fail

So now I have to go in there and pull off my plenum , find an EGR and replace it.
The mechanic admitted to me that the EGR doesn't do much in a rotary and that it's a BS california law thing, in addition to the car running very clean for a rotary.

Anyone know where to start looking for an EGR? I checked mazdatrix and they don't carry them.

Anyone done this job before and have any advice or cautions for me?

Thanks, TW

P.S. I hate california