Ok man, let us know. I still have the original radiator, never run hot except when thermostat stuck closed. That will stop you in your tracks. I hope the water pump is your problem.
Dan

 

Well, I finally got the time to install the new water pump and she still runs hot - 210+ degrees.

This is by far one of the most frustrating issues to deal with. I think I may check the freeze plugs next, but who knows when I will be able to get around to doing it. https://mustangforums.com/micons/m13.gif

Not sure where to go from here...

 

Well, after sitting on the couch frustrated as hell, I decided to richen the heck out of her to see if that helped. The weather here in California cooled off tonight, but when I did my test run she never broke 200 degrees.

It's definitely progress, but the real test is tomorrow when it's hot. Also, I am running 100% water, just in case I needed to take the radiator out I didn't want to waste the coolant.

We'll know tomorrow. Wish me luck, fellas.

 

You're going to regret running pure water when you drain it out and get a bunch of rust flakes. Fill it halfway with coolant and find yourself a sealable catch pan if you have to drain it out again.

 

Hey there Starfury, each time I run pure water I drain it that same day so I'm sure rust will not be an issue.

 

You're not drying it out every time you drain it, and unless you're popping outthe block drain plugs too, it's not even draining out completely. Any moisture in the block at all without the anti-corrosion properties of coolant is going to cause rust buildup.

 

You see, that's why I'm on this forum. I still learn something about this car everyday.

Thanks for the tip Starfury.

 

I learned this the hard way. I broke my engine in on pure water, but didn't get a chance to drain it and fill it back up with a coolant mix before I took off for school again. It was only sitting for a couple weeks, but it was long enough to cause significant rust buildup. I was flushing rust particles out of my cooling system for a long, long time after that.

 

A couple of things:

Thermostats can be defective and not open at the right temp.

They sell flush kits at parts stores that will let you adapt your garden hose for less than $10 (illegal to use in some beach communities).

Remember, if you just drain the radiator, rust will remain in the jacket, so flush your entire system until the coolant is free of debris.

Starfury is right: rust can happen very quickly. Always have some coolant in the mix.

I installed a 3 row Modine 10 years ago and never looked back. The temp gauge never goes beyond "E", even in the desert.

I strongly recommend a coolant filter, the clear ones that attach to your top hose. Your radiator will last forever if you clear rust buildup out of the filter periodically instead of flushing a hot engine after rust blockage problems happen.

Good luck.

Carlos