Have an IR temp gun and a Cadillac? Please post some underhood readings.

[TJ Hopland]

 With the summer more or less upon us more and more temp issues seem to be coming up which got me thinking it would be nice if those with and apparently properly operating car could take some readings under the hood and post them along with the basics about the car so those that are having issues or think they have issues have some sort of reference point.

I will start with some readings I took several years ago.  I don't have the time or money right now to get my car out of storage to get current readings.   

Thinking you get the car info first so people can just skim the first line looking for a car similar to theirs.

73 Eldorado
 
Fairly recent mostly stock rebuild 
Custom dual exhaust 
Custom EFI system
No AC or condenser installed
10 year old OE style copper radiator
Aftermarket flex fan
Stock 195 stat

Ambient temps 75 F at idle after a nice cruise

Top of water outlet 222
Stock sender location 235 (gauge reading just under 230)
Upper hose just above the outlet 196
Upper hose at the radiator 200
Heater core return to radiator 168
Lower hose near radiator 160
Radiator near cap 188
Radiator fins pretty much everywhere 130
Front carb base of intake 248
Passenger side exhaust ports on head 380 (#1 about 320)
Drivers side exhaust ports on head 350 (#2 about 300)       

[ghhatley]

Thanks for this post. I needed these numbers for my 75

[chrisntam]

98 to 100 degrees ambient, yes, I'm sweating (Dallas, TX)

About 400 miles on rebuilt '70 507 (.030 over), true 10:1 compression, mild cam, new 4 core radiator. A/C condenser in place and operative.  Single exhaust, 7 blade eldo flex fan.

Top of water outlet 185
Can't access stock sender location
Ported vac switch has my temp sender (aftermarket gauge reading 210)
Upper hose just above the outlet 198
Upper hose at the radiator 185
Heater core return to radiator 172
Lower hose near radiator 204 (this concerns me)
Radiator near cap 204
Radiator fins pretty much everywhere 160 (can only access the top 2 inches)
Front carb base of intake 181
Passenger side exhaust ports on head 500 - 550 I measured the exhaust manifold
Drivers side exhaust ports on head 475 - 530  I measured the exhaust manifold

I'm surprised my lower hose is reading 204, it should be less than the incoming.....

I'll be adding two aftermarket pusher fans to the condenser as soon as I feel like it.

[Scot Minesinger]

Chris,

Those IR guns are handy, but not always to be relied upon.  Running at 210'F temperature gauge, provided it is a decent one when it is 100'F outside is probably about right.  You did not write if a/c was on and if you were in slow traffic or it was open road driving.  If it is 100'F outside and your system was malfunctioning you would overheat.  If the a/c was running and it was heavy traffic, that is a fantastic result.

I ran two of my 1970 Cadillacs today and it was only 85'F outside and no a/c (top was down) and it was around 195'F with a real accurate Autometer gauge.  My engine is fairly stock, except it was rebuilt 38k miles ago, bored 0.30 over so it is a 478 now, it has a MTS modified intake (they took a stock manifold and machined it), 4 row radiator, 7 blade fan, plus duals.  Days like today make it all worthwhile!

I just do not get why your Cadillac would be running hot if it is has the commercial fan, 4 row radiator, and engine is in proper adjustment?

[chrisntam]

The readings taken were with the a/c off and idling in the shade.  I too have the MTS shaved intake (under the carb), I believe the exhaust crossover is blocked as well.

While driving down the road w/ a/c on today, it was about 195 engine temp sender is located pvs location.

I wouldn't say it's overheating, but will add the fans regardless, really to help at idle or while in traffic.  2 12" fans pictured below.