Overheating issues, what to check for?

[stylin99]

I just bought a '93 5.0 LX vert that has an overheating problem. The temp gauge climbs pretty high when you're sitting still for prolonged periods, especially when it's warm outside. It's went past the 3/4 mark before I shut it off.

I flushed the radiator and put 50/50 new coolant in.

I'm trying to locate the problem but I'm pretty sure it's the radiator. Can anyone shed some light on what to check if the car isn't cooling? The fan works. The thermostat appears to work, since it kicks in at around 200 deg (halfway on the gauge) but I can't tell if there's an intermittent problem there.

Any ideas? What am I looking for on the radiator to determine if it's bad?

 

[TurboMustang370]

stylin99,
As far as checkin the radiator, first look to see if the fins are damaged on the front and rear... if they are, it may not be allowing sufficient airflow.
Second, if you can, buy a pressure tester from like sears or pepboys, normally you can get a cheap one and sometimes the auto stores will even do it for ya.. this is to check if there are any holes in the rad. (which if you're not losing fluid, you probably dont.

My opinion, for the $5 a thermostat and .89c for the gasket, I would replace that just to have it done.

Hope I answered your question.

 

[bmorrisj]

burp the cooling system, and check your fan clutch....if you can spin the fan by hand and it goes more than half a turn the clutch is bad...especially if the motor is hot, the fan should not really turn at all by hand...

 

[HISSIN50]

in general, overheating on the highway indicates insufficient radiator flow. if overheating/running very hot in traffic, that indicates a fan issue.

are you basing this on the stock gauge? if so, dont. get an aftermarket gauge.

i might replace the stat with a quality 180 - you have no idea what the condition of the old one is. and get a new radiator cap - if the cap is not sealing and holding pressure, the effective boiling point is reduced, and thus overheating can occur.

good luck.