Today I finally got around to calibrating my guage with a coleman stove and pot of water. Took a while to figure out I had to ground the guage, duh! Anyway here goes. 200 deg was actually halfway between the heavy hashmark by the 200 and the one at 12 oclock. 210 was to the right of the 12 oclock hashmark. It would appear my thermostat opens a little early because the car generally runs just under the hvy 200 hashmark which probably translates to 170 175 deg. On the hiway my needle is usually at the 12 oclock hashmark meaning it runs about 205* which I guess is acceptable. The hashmark after 12 probably translates to 220* which is where it runs on the hiway with the a/c on. Is 220* too high?? Or would it be within reason? I just added some water wetter also, to see if I can bring it down a few degrees.
Comments ? Ideas?
ESU

 

In 1979 the L-82 with A/C had a spoiler extension from the factory. It is about 4 inches wide and made of a flexible, rubber-like material and mounts to the regular spoiler. Mine is in place and it runs at 180 on the highway and 185 with A/C on a 90 degree day. Perhaps you need more air flow at highway speeds and if you didn't add this when replacing your spoiler I would suggest it. Seems like you've done everything else. Do you have a spring in the lower radiator hose to keep it from collapsing? Dr. Rebuild shows this extension and mounting kit in the catalog. Good luck.

 

IMO 220 should be ok.But your readings/calibration are still approx.Mine at HWY speeds are 200 and 180 city traffic.
With A/C maybe 210-215 pulling hill in the desert with ambient air of 100 degrees...think my gage reads high,but don't know for sure.....

 

No I didnt install the extra piece to the spoiler. I will look at docs catalog though. How does it attach? No clearance problems? I thought it was the lower hose so last year I pulled the end off the water pump and felt the spring inside. Added water wetter yesterday and that didnt seem to make any difference. I'm at wits end with this. Gonna try a flex fan, probably wont help but at this point whats another 30 bux. ALso as the car runs hotter my a/c starts runnin hotter also.

 

i would think 220 is right at the upper edge of where i would want it to be....not a lot of wiggle room there for getting stuck on one of those lovely bridges....

 

There is a metal support/frame that the spoiler is riveted to. On my early build original the rivets are large head with natural finish-black finish is available if you prefer. This frame is then attached to the original fiberglass spoiler-I don't recall whether rivets or bolts. Doc rebuild lists all these parts. Good luck.

 

Marv,
I looked at Docs website and cant locate the parts in question, what are they listed under?

 

Go to the main page,click on "a-z" parts index,then click on "S",scroll down to "spoiler extensions",68-82.

They rivet on...cost about $30 bucks..

 

Or on page 199 of the hard copy catalog. The prices are out of date in both formats but you need "L" HD Rad Extension and whatever mounting hardware you prefer. I looked at mine and the retainers are actually two thin strips of thin metal (left and right sides) and are located on the back side of your fiberglass spoiler. You could probably make your own if you're not NCRS concerned since they are actually just solid material for the rivets to be peened over on. They are about 1/2-3/4 inch wide and thin enough to bend-maybe 1/8 inch thick. I don't think simple washers will suffice due to the wind/air pressure at speed. The rubber extension is located on the front side of the fiberglass and the rivets go through all 3 layers - like a sandwich - with the large head to the front side on the rubber. Then mount it as an assembly. As to clearance issues, I have just barely scraped mine on really high curb conditions but not on normal parking lot stuff. It's flexible and you likely won't "hang" the nose out that much anyway. Good luck.

 

[QUOTE=ESU]OK, took a 50+ mile hwy run today with temps in the hi 80's. It stayed at the 2nd hvy mark till I got on the hiway. Steady 65 mph the guage slowly creeped up to the 12 o'clock position. Stayed there till I turned the a/c on then it crept up very , very slowly till it just made the first light, unnumbered hashmark after the one at 12 o'clock. If I slowed down to 55mph the temp would come down a little. A/C off and it came down pronto. Again, new 4 row rad, new water pump, new thermostat, new motor for pete's sake, doc rebuild seal kit and I'm still no cooler than I was last year before I replaced it all. I'm going to try and calibrate that guage sometime this week, I'll brake out the coleman stove and a pot of water and see exactly where I stand unless somebody has idea. Also I installed the spoiler under the front end that was missing when I purchased the car lasy year. Maybe I'll take out the headlight buckets to let more air in lol. Either that or move to ALaska!



Try replacing the temp switch. It's an $8.00 part from Auto Zone. It screws into the side of the block. Drivers side. When you take the old one out, be ready to put the new one in because you will lose some antifreeze . Wait till the engines cool. This fixed my problem on my 79 Vette.

 

I changed it once but the new part was even more out of calibration than the first one so I put the old one back. Now that I have this one calibrated I feel a little better about knowing exactly what temp I'm running at.
I did however calibrate the guage with the engine off. I've since noticed that with the engine off but key on my reading is slightly different than with the engine running! When I turn the key off the temp on the guage drops several degrees so if I'm figuring this out correctly that means when the car is actually running I'm getting a slightly higher reading than it actually is. Must have something to do with the voltage difference between off and on.
Can anybody confirm if I'm correct or is this another anomaly peculiar to my car???

 

By the time you finish with the retainers and rivets you're into it for another 100 bux, I guess it nevers ends does it?