Where are all the running hot posts?

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1969383S

1969383S

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Has everyone resolved their issues or is Covid-19 dampening things?

Went out last weekend in 90+ and all good for me.
 
All cool for me here, not even close to running hot.

180° thermostat keeping the temp under control while running 2500 rpm for a half hour during the break in.

Lots of air moving through that radiator with that 18" 7 blade clutch fan and fan shroud setup.

20200712_191319.jpg
 
Reduced traffic means less stop and go. Driving home from work today, there was almost no traffic on the freeway.

I did see a pale yellow 68 fastback and a light blue 65 or 66 drop top dart with a white top.
 
Ran into a 69 RR and He was running cool inside and out! Would be nice to have Air conditioning, but when moving in the A-body not so bad with the Air boxes open and windows down.
 
Staying cool. I need to take a photo of the evap temp when it's in the mid 30's.

20150706_141853.jpg


20150719_163339.jpg
 
Mine normally runs about 170.

...unless the AC is on. Then it can go to 210 or more.

Still trying to figure that out.
 
YY1 said:
Mine normally runs about 170.

...unless the AC is on. Then it can go to 210 or more.

Still trying to figure that out.
Click to expand...

You are basically dumping the cabin heat into the air that passes through your radiator. I am no physicist so all I can say is to check out some videos on thermodynamics on YouTube.
 
YY1 said:
Mine normally runs about 170.

...unless the AC is on. Then it can go to 210 or more.

Still trying to figure that out.
Click to expand...
I about to install ac and the kit came with it's own 12in fan for the condenser...
 
It's a factory AC car with the factory system but 134a.

If I don't shut off the AC before it gets to 210 it will overheat.


I can't imagine everyone with an AC car in 1973 doing that.
 
YY1 said:
It's a factory AC car with the factory system but 134a.

If I don't shut off the AC before it gets to 210 it will overheat.


I can't imagine everyone with an AC car in 1973 doing that.
Click to expand...
Of course I could name some of the obvious like maybe a bad thermostat or a partially clogged radiator or I've even pulled a water pump apart and only two of the eight fins we're still operable and the other six flaps had broken off...
 
YY1 said:
It's a factory AC car with the factory system but 134a.

If I don't shut off the AC before it gets to 210 it will overheat.


I can't imagine everyone with an AC car in 1973 doing that.
Click to expand...
Is the AC unit cooling very well?..
 
Without AC on runs 170 degrees all day (aftermarket sunpro gauge verified by IR), can idle for any amount of time, stop and go traffic, you name it.

AC blows about 45-48*
 
YY1 said:
It's a factory AC car with the factory system but 134a.

If I don't shut off the AC before it gets to 210 it will overheat.


I can't imagine everyone with an AC car in 1973 doing that.
Click to expand...

I just re-read my post, and I noticed that I came across as a total ***, I apologize for that. I misunderstood the direction of your question.

Are you running those horrid accordion hoses to and from your radiator?
What condition is your water pump in?
What condition is the radiator in?
Water/antifreeze mixture?
Thermostat issues?

When I replaced my radiator, I mocked up the hose path with a coat hanger and figured out the best shapes for hoses. I went with bent silicone hose sections with a lumen the diameter of the largest hose fitting and stepped down to the radiator fitting diameter at the radiator. A larger diameter pipe will offer less resistance, less pressure which is good in my eyes.

Also, at a bend, go with two 45* bends rather than a 90* bend.

IMG_20200718_0738268.jpg
IMG_20200718_0738048.jpg
IMG_20200718_0737460.jpg
 
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YY1 said:
Without AC on runs 170 degrees all day (aftermarket sunpro gauge verified by IR), can idle for any amount of time, stop and go traffic, you name it.

AC blows about 45-48*
Click to expand...
Yeah that is a bit of a stumper...
 
YY1 said:
Without AC on runs 170 degrees all day (aftermarket sunpro gauge verified by IR), can idle for any amount of time, stop and go traffic, you name it.

AC blows about 45-48*
Click to expand...
Sorry best I could do was just Google it..
At least it gives a direction of things to check... but really some of the things I was mentioning that we don't know for a fact like a partially clogged radiator or a defective water pump..
Screenshot_20200718-074030.png
 
Yeah, I've been leaning towards bearings in compressor going bad.

Worst possible case, etc.....

61,000 original miles. On almost everything.

When I had the engine out to replace the freeze plugs, I pressure washed the water jackets and picked out a handfull of rock like deposits, so it should be fairly free of cloggage in that area.

Water pump was replaced at that time.

If it ran borderline hot without AC, I'd suspect one of those other things, but it actually runs cooler than I'd think is normal otherwise.
 
YY1 said:
Yeah, I've been leaning towards bearings in compressor going bad.

Worst possible case, etc.....

61,000 original miles. On almost everything.

When I had the engine out to replace the freeze plugs, I pressure washed the water jackets and picked out a handfull of rock like deposits, so it should be fairly free of cloggage in that area.

Water pump was replaced at that time.

If it ran borderline hot without AC, I'd suspect one of those other things, but it actually runs cooler than I'd think is normal otherwise.
Click to expand...
I had a 318 block that was just packed full of what I know the previous owner like to use... Radiator stop leak instead of tightening hose clamps... And radiator shops are the worst culprit of using the stuff... It could possibly not be able to cool the condenser when it starts warming things up as well.
 
I'm looking for a fast idle solenoid.

I have one from an 86 but I think it's toast.

Those are not super easy to find.

If I put it in neutral at stop lights, that seems to help.

However, I don't think people did that when they were new, either.

Idle is set at book spec (IIRC 750 and drops to 600 with AC on).
 
YY1 said:
I'm looking for a fast idle solenoid.

I have one from an 86 but I think it's toast.

Those are not super easy to find.

If I put it in neutral at stop lights, that seems to help.

However, I don't think people did that when they were new, either.

Idle is set at book spec (IIRC 750 and drops to 600 with AC on).
Click to expand...
Right there is a circulation issue...
 
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