Overheating

[VTMopar]

Help!    Took the Challenger out for the first road trip after overhaul about 300 miles (to Hemmings Car show in West Lebanon, NY).  She ran great -- but without the A/C hooked up (yet) -- she ran a bit the high side of the temp guage.   Belts seem tight enough -- radiator was tested before the overhaul -- coolant is new and level right where it was when I left.   Could it be the fan?   

Any ideas on what might be going? 

Vermont MOPAR

 

[MEK-Dangerfield]

Forgive my ignorance of your setup.  What size engine, and what size radiator? How many blades on the fan, and do you have a fan shroud?


  Mike

[VTMopar]

All original -- 360 engine; 26 inch radiator w//shroud; 7 blade fan  -- went through the complete engine & bay this winter.....   

Question:  Should the fan blade turn freely when the engine is cold/not running?    Belts are tight....
Also, was wondering if it could just be a bad thermostat?

Vermont MOPAR

[Chryco Psycho]

if the thermostat is bad it will cause this also timing too far retarded or carb too lean 

[Mopar73340]

Fan should should not turn free when the engine is cold or warm. There should be some resistance. Also from experience if you replace the fan clutch, make sure you go with the heavy duty one for the 7 blade fan as the std duty one will not spin the 7 blade fan fast enough for proper cooling. My 340's run 185* on 90*+ days with 7 blade fan, heavy duty clutch and 26" radiator with the A/C on. Just my 

[Bullitt-]

Some thermostats are more restrictive than others, I have read that Mopars need the low restriction type to flow correctly.

[pink panther]

if the thermostat is bad it will cause this also timing too far retarded or carb too lean 

cheapest place to start with the thermostat

[ted]

u using the factory guage?

[VTMopar]

Thanks for the thoughts -- will start with the thermostat -- Yes, the factory guage -- it is accurate.

Vermont MOPAR

[DJW]

It was the fan thermo-clutch.....   glad we found it!    Thanks for all the advice!

Vermont MOPAR

[miketyler]

Thats great  news. I now have my car all put together and it still runs a little hot. We drove it around the neigborhood today and it crept up to the upper end of the operaitng range. My car is a 340 with a stock cam. It also has a newly revamped 3core radiator and dual electric fans. It seems to be doing a bit better than it did last year when I last drove it.  I appreciate everyones help and advice on that topic I started last year called 'cooling the engine down"

I will double-check timing this evening but how critical is the carburetor tuning? I am still running the Holley Street Avenger and haven't touched it since I know little about them.  If it could be contributive, how can I test and/or eliminate it? Replace the carb or ?  Are vacuum leaks contributive to higher engine temp?

[Chryco Psycho]

timing , running lean & vacuum leaks can all cause increased heat , the last can kill the engine quick

[ted]

And you know this how?

Thanks for the thoughts -- will start with the thermostat -- Yes, the factory guage -- it is accurate.

Vermont MOPAR

[Chryco Psycho]

a vacuum leak can increase heat in a cylinder just like adding oxygen in a oxy actelene torch , it can melt the plug or even the piston if left lean

[miketyler]

that makes a lot of sense to me. The carb piece of this is the only thing I haven't changed. Will give that a go.