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70 Big Block, normal temp range?

Old Aug 5, 2010 | 09:43 PM
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Default 70 Big Block, normal temp range?

My temperature gauge seems to level off around 210 degrees.
Is this normal running temperature?
How do I tell if the fan clutch is failing?
How stiff should it be once the engine is fully warmed?
I think the thermostat is 180, could be 190.
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Old Aug 5, 2010 | 09:52 PM
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Originally Posted by BBCorv70
My temperature gauge seems to level off around 210 degrees.
Is this normal running temperature?
How do I tell if the fan clutch is failing?
How stiff should it be once the engine is fully warmed?
I think the thermostat is 180, could be 190.
my 72BB has a brand new engine, and oem radiator. When I had the crate motor installed last year I had the original radiator cleaned and then installed an electric fan. Make sure you have a correct reading temp sender. In the hot San Antonio summer mine would idle at 180-190 degrees. I at first used an autozone temp sender and it said 220. I read on here that parts house senders read incorrectly. I bought one from Lectric Unlimited and read their ohm vs temp reading. I verified with their chart that their sender read correctly and installed it. with a 180 degree thermostat the temp gauge never goes above 190.
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Old Aug 5, 2010 | 10:01 PM
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Thanks

I'll check into the sender. I have access to a temperature gun which I just point and
pull a trigger, gives the surface temp of what I'm pointing at. Wonder is this may help me determine whether it's running hot?
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Old Aug 5, 2010 | 11:43 PM
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My 68 BB is .030 over and it runs about 190 with out side temp of 85 and a 180 T-stat.
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Old Aug 6, 2010 | 11:55 AM
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210 is okay. A bad fan clutch will windmill after the car is at operating temperature and the engine is turned off.

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Old Aug 6, 2010 | 06:16 PM
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My fan clutch never seems to really lock up. Even when the car is fully warmed up I can spin the fan without much resistance.

Should the clutch become stiff when the engine is heated up?
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Old Aug 6, 2010 | 06:23 PM
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I have an IR temp gun - where should it be pointed to get an accurate reading?
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Old Aug 6, 2010 | 08:45 PM
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I assume the temperature sending unit. See if the IR gun reads the same?
Other thought was the expansion tank. Anybody have some other suggestions?
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Old Aug 7, 2010 | 09:37 AM
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Originally Posted by BBCorv70
My fan clutch never seems to really lock up. Even when the car is fully warmed up I can spin the fan without much resistance.

Should the clutch become stiff when the engine is heated up?
The general role is to watch the fan when you shut off the engine (when fully wamed up) if it turns more than 3 revs before it stops, then you have a bad clutch.
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Old Aug 7, 2010 | 09:39 AM
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Originally Posted by mar
I have an IR temp gun - where should it be pointed to get an accurate reading?
I point it to the thermostat housing, gives me a pretty accurate readings there, unless you have the chrome one, then your IR gun wont pick up the correct reading because it can't read the temps off a shiny, mirrored surfaces.
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Old Aug 7, 2010 | 01:42 PM
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Originally Posted by BBCorv70
My temperature gauge seems to level off around 210 degrees.
Is this normal running temperature?
How do I tell if the fan clutch is failing?
How stiff should it be once the engine is fully warmed?
I think the thermostat is 180, could be 190.
Normal temp would be the factory T-Stat setting for that year car

Fan clutch is as others have indicated, check during shutdown

There will be some drag present but you should still be able to spin it fairly easily

verify T-stat to determine temps

Neal
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Old Aug 7, 2010 | 01:45 PM
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Originally Posted by BBCorv70
My temperature gauge seems to level off around 210 degrees.
Is this normal running temperature?
How do I tell if the fan clutch is failing?
How stiff should it be once the engine is fully warmed?
I think the thermostat is 180, could be 190.
Mine runs around the same temp as yours

Rick
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Old Aug 7, 2010 | 08:26 PM
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For a 69 L46, 210 is the normal operating temp for emissions purposes. Have to assume your 70 is the same. Info came out of the owners manual. I do now run mine at 180.
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Old Aug 7, 2010 | 09:44 PM
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If these cars are running 190-210, what's the point of a 180 or 190 thermostat?
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Old Aug 7, 2010 | 09:54 PM
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Originally Posted by UBETRUN
If these cars are running 190-210, what's the point of a 180 or 190 thermostat?
That's for running in sub zero ambient temps
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Old Aug 8, 2010 | 06:54 AM
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Originally Posted by UBETRUN
If these cars are running 190-210, what's the point of a 180 or 190 thermostat?
Thermostats do not determine how cold the engine runs, only at what temp does it allow water to circulate.
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Old Aug 8, 2010 | 10:40 AM
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Originally Posted by baxsom
Thermostats do not determine how cold the engine runs, only at what temp does it allow water to circulate.

I know how a thermostat works and if your car's "normal" operating temp is above the thermostat's opening temp, the thermostat is not doing anything in that application. Other than warming a cold motor up faster, the thermostat is wide open during normal operation.

This is a good thread, saved me from buying a thermostat for my new big block.
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To 70 Big Block, normal temp range?

Old Aug 8, 2010 | 11:30 AM
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Originally Posted by UBETRUN
I know how a thermostat works and if your car's "normal" operating temp is above the thermostat's opening temp, the thermostat is not doing anything in that application. Other than warming a cold motor up faster, the thermostat is wide open during normal operation.

This is a good thread, saved me from buying a thermostat for my new big block.
You DO need a thermostat, I remember last winter I was driving on the highway with around 50* ambient temp and the engine temp was WAY too cold! .. I used a 160* thermostat and the engine temp was right at about 160-165*, so I imagine if it didnt have a thermostat it would drop to 150* or so which is just as harmfull to the engine as over-heating.
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Old Aug 8, 2010 | 01:23 PM
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Originally Posted by HamadUP
You DO need a thermostat
My car will not be driven in the winter.
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Old Aug 8, 2010 | 02:06 PM
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then thats another case, as my car is my daily driver all year around.
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