Burping a radiator/ overheating

[521newbie]

I've heard the term burping the radiator and want to know how this is done?

My 521 runs at 3/4 on the temp gauge to sometimes right up to red line. It didn't run this hot when I bought it, only about half way. I discovered the previous owner had no thermostat installed so I put one in and flushed the radiator. Now it runs hotter than before. I'm at a loss there.

I have a Fiero radiator to put in but I haven't figured out how to mount it yet. If anyone has done this I'd like some pointers.

Thanks for the help.

[datsunaholic]

"burping" is done to clear an airbound system. Doubt that's the problem. Prior owner porbably removed the thermostat because it was running hot- it's running hot because 1) the radiator is plugged up with deposits or 2) the timing is off so much it's running hot.

 

Flushing the radiator doesn't help when they're really plugged up with scale- only fix there is to replace or have it rodded out, neither are cheap.

[MikeRL411]

It might also help to install a Prestone flushing Tee in the top heater hose. When you fill up, open the tee to let all the trapped air out. Then trickle in a little coolant to insure a complete fill.

[mazdat]

if theres nothing wrong with the engine, like the headgasket or timing, its going to be the radiator, have it taken out and have it rod out