and so is the iroc,well really overheating,on Tuesday discovered the plastic end cap,drivers side was cracked,lost a little anti-freeze,took to the house,noticed temp change reading high @250,no fans,pulled the radiator had new end cap,passenger end cap changed last May,put in car,test run for leaks and topped it off,today in traffic,@250 again,still no fans,checked level,down a little,took it on highway,thermo not opening until gauge reads @240,opens,goes down just below 220 mark,as long as moving seems to stay under 220,as soon as stop in idle,straight up she goes,no fans,get home ,levels OK tighten lower hose clamp,start,idle in driveway,up to red,no fans??stop ,turn ignition on,passenger side fan runs ,are any of the fans supposed to run when car off??do i have bad thermo??do see something in reservoir,kinda black straks,blown head gasket??don't want to popp a head,any suggestions???89 IROC 305 TPI 5spd

 

Not to flame you, but complete sentences would help a lot in understanding your problem.

You keep saying no fans, does that mean they're not coming on, that's your problem right there. The stock fan temp switch is set at 220*, getting a lower rated one would help a lot.

The stock stat should be 195* and not opening till a little past that, 240* is definately too high, I'd suggest getting a 180* while you're trying to fix things.

Also, be sure the temp gauge is reading properly.

 

250*!!! gross...I get paranoid when I pass 195*F.

The fans should be on if the engine is 240*.