This one is frustrating..my GF's 89 RS just keeps getting hotter and hotter as its driven. It can't go on the freeway without going to 220 and that just seems way to hot for a car with somewhat of a grill (compared to my firebird I mean) a new radiator and a 160 thermastat...is that how hot these are supposed to run?!? Car has electric fan wired to run all the time......has a carb, 305, hedman headers and 3inch exhaust. Should run pretty cool the way its set up..Any suggestions?

 

Is her front air dam/skirt still there? It redirects air up from underneath the front of the car and through the rad.
I had a problem like that before and turned out mine was missing.

 

F355,

The air dam is a very good thing to check. There should also be a baffle on either side of the lower radiator support to direct all the ram air through the radiator and away from the openings aside the radiator shell. These are important, but less than the air dam itself.

If that all checks out, you should also verify good flow from the coolant pump. With the radiator cap removed and engine running warm, the coolant level shoudl fall almost instantly when you "blip" the throttle.

Also, make sure the lower radiator hose is not kinked/collapsed. There should be a wound wire "spring" inside the lower hose to prevent it from being sucked flat when the engine RPM increases. If this wire was left out when changing a hose, or has corroded away, you could have a problem with flow at speed.

Of course, you should also look for corrosion in the cooling system. Deposits at the discharge ends of the radiator tubes (visible through the radiator cap) are a sign that the cooling system really need to be flushed.

If you are flowing well, the radiator and system are clean, and the lower hose is intact, check the coolant concentration. Any antifreeze concentrations in excess of 35% start to lose a little cooling efficiency, and beyond 50% really starts falling off.

Look for bubbles in the cooling system while the engine is running as well. These could indicate a compresion leak into the cooling system and will create hot spots in the heads, raising overall coolant temperature.

 

Good tips vader....I'll check those tomorrow. Thanx. I think it may be the lower radiator hose cuz it does look pretty old and It would make sense. Camaro's have airdams??? Hmm.....just looked...mine must be long gone. Doh!
Chris

 

The airdam bolts under the car just below the radiator.

I snapped pics of my old '82 airdam versus a brand new '88 IROC piece:

http://members.fbody.com/kevinc/airdam/airdams1.jpg

http://members.fbody.com/kevinc/airdam/airdams2.jpg

 

Also check the <A HREF="http://www.gmtips.com/3rd-degree/dox/tips/cool/ac-strips.htm">A/C Condensor Sealing Strips</A>. This was brought to my attention by Desert86Roc. They get old and brittle and blow out. Then some of your incoming air is slipped right past the radiator. This should be good for a few degrees.

 

is your timing retarded too much?
:hail:IROC-Z

 

Is your carb tuned well? A lean condition would raise temps too.

 

check the censor

 

Why, doesn't he like these posts?
Rob

 

Is it that hot or is the gage bad?

If the air dam is in place, I dont understand why it would be so hot.