1971 ElDorado eng. temp.

[Cesar091665]

Hi everyone, I just installed a temperature gauge on my car to get a better idea of what the eng. temp. is.  I've had a couple of issues with it overheating on me, I believe I have addressed those issues but I'm not sure what the "running temp" is. I flushed the system and removed the thermostat, it seems to run around 220. Is that about normal?   
Also a/c clutch went out and almost burned the belts off. Thinking of removing the system since it doesn't work anyway and I don't see the point of having a/c on a convertible, any ideas or comments on that? 

[TJ Hopland]

These cars do seem to often run on the warm side.  200 would be normal based on the factory 195 thermostat so 220 is a little higher.   One of my theories is that they got rid of the gauges because customers were complaining that they run hot.  No gauge no complaints.   Does it stay at 220 all the time or just on a hill climb or stuck in traffic?    If its there all the time you first want to try and verify that the gauge is accurate, if it is then start going through things to see if there is a problem. 

I don't see a problem removing the AC stuff if you don't plan on fixing it anytime soon.   71 likely still has a listing for the shorter belt needed to bypass the compressor so that part should be easy.   You could also remove the condenser from in front of the radiator, it could be packed full of dead bugs and dirt and slowing down the airflow.   Just put all the parts together on a shelf in the garage or basement so if you ever want to get it working you can.  You should be able to find plastic caps for the open ports that will be left under the hood.   All that stuff will need service and flushing to get it working again so its not critical to cap them but you don't want lots of crap getting stuck in there.   Also note that one of the rear AC compressor brackets threads into an intake runner so you will need to put a bolt back in the hole to plug the hole or you will have a leak. 

["Cadillac Kid" Greg Surfas 15364]

220 is just about what these cars were designed to run at.  When they get to 230 in traffic the thermal switch allows manifold vacuum directly to the distributor vacuum advance to help "keep the cool".  Aside from checking for a clear radiator both inside and out, I would verify that all the intended devices are installed and functional, such as distributor vacuum advance, thermal switch (located in the front of the motor just under the drivers side cylinder head.
I would however recommend re installing the (special to Cadillacs because of the bypass) thermostat.  Without it water flow can actually be to great to allow proper time in the block to pick up the correct amount of heat.
As TJ said, temperature gauges were eliminated because no one who was used to seeing water temperatures at 180 degrees was comfortable with the new temperatures. Case in point; I put in a gauge in my 76 only to disconnect it after watching the 210-230 degrees on the dial.
Greg Surfas

[chrisntam]

My newly rebuilt (1000 miles) '70 runs down the road at about 190 to 195.  In traffic, it easily creeps up to 210 or 215.  Once moving again, it goes back down.

Where are you located?  South Texas?  Minnesota?  Ambient temp seems to make a difference.

I have 180 stat in mine, definately recommend putting one in.

chris.

If the car is otherwise good shape, get the a/c working!

[Cesar091665]

Thanks for all the great advise! I live in Sacramento, California, and although temperatures during the summer are usually in the mid to upper 90's, this week was all around 105!  I took a closer look at the condenser and a lot of the fins were bent and damaged so I removed it. I will eventually rebuild the entire a/c system, but for now I'm just trying to make it mechaniclly reliable. I have heard the same about having a thermostat in place to help them cool better, so I will install a new one as well. The one I took out looked like it had been in there for a long while. Right now the car runs in the 190 - 200 range when moving, once I start stopping at lights or traffic it claims to 220 - 230 range and it takes it a while to get back down. (Haven't test it without the condenser yet) Considering the condition of the condenser, I'm thinking that's going to help.
I'm also finding out the car has a few electrical problems, so I'm going to start addressing those next!

[TJ Hopland]

Greg mentioned the proper thermostat.   The difference between the proper one and a typical one is a large washer at the bottom.   Most stats don't have that bottom washer.   This washer closes over the bypass port in the block when the stat opens so it forces all the water to go through the radiator.    Its like a 3/4" hole so if that port is open you would be loosing some cooling capacity.

Does yours have a clutch fan or is it fixed?   IF its a clutch it may not be spinning the fan like it should .

Lots of active folks here with Eldo's from that era so if you get stuck feel free to ask questions. 

[35-709]

Pictured below is what the correct thermostat will look like.

[Cesar091665]

Thank you TJ Hopland and 35-709, I'll make sure to get the right one, your information really helps. My car does not have a fan clutch, and according to my shop manual it didn't come with one.
I took the car out for a test drive yesterday after removing the condenser, ( it was another hot one in northern CA yesterday, 101) and the car ran great, according to my temp. gauge the car stayed in 190 - 200 range and during traffic it never went over 220, and as soon as I started rolling again the temp would drop. It's going to take a while before my wife trusts this car as it's almost left us stranded twice, once due to overheating, (That was a bad one ) and the other one when the a/c clutch locked up on me and nearly burned the belts off!
Both times I was able to get the car home though!