Temp goes from 200 to 225 when A/C is on - ZR-1 Net Registry Forums

Prez1967 · 08-22-2023

I cant recall if this was the case since I bought my car but I recently noticed that when Im cruising around without A/C, the car is at a stead 200-202 degrees.

When I turn the A/C on, the car's water temp creeps up to 223-225.

Is this normal? or do I have to roll my sleeves up and dig in...

Jagdpanzer · 08-22-2023

What radiator do you have installed?
What temperature are the fans programmed to come on?

Sent from my iPhone using ZR-1 Net Registry

Prez1967 · 08-23-2023

Quote:

Originally Posted by Jagdpanzer

What radiator do you have installed?
What temperature are the fans programmed to come on?

Sent from my iPhone using ZR-1 Net Registry

I have an aluminum radiator in the car now. I flushed it not long ago when I did suspension work and steering rack since I removed it and Haibeck also flushed system when it was up with him at the beginning of the year.

He also programmed the car to run fans at 160 or 180 I think? Whatever his standard practice is.

Dynomite · 08-23-2023

Quote:

Originally Posted by Prez1967

I cant recall if this was the case since I bought my car but I recently noticed that when Im cruising around without A/C, the car is at a stead 200-202 degrees.

When I turn the A/C on, the car's water temp creeps up to 223-225.

Is this normal? or do I have to roll my sleeves up and dig in...

Haibeck both fans on 205 off 200.....
What was air temperature?
What was engine rpm? You say cruizing so must be over 2,000 rpm unless you are in 6th....

With AC on engine temp may rise a bit...

Prez1967 · 08-23-2023

Got my stats mixed up.

T-stat is either 160 or 180 (dont remember) fans are set to whatever Marc's standard set up is.

Intake Air Temp?

It was SUPER hot a couple weeks ago when I was driving around in heavy traffic and with the A/C off, the temperature was stable at 200 degrees. When I'd click on the A/C it would stabilize at 225. Same result when I was going highway speeds.

It was considerably cooler the last time I drove the car had the same results.
Im planning on driving the car tonight. Can check air temp tonight and report back

Young1 · 08-23-2023

I am experiencing the same thing as OP. Never have before. All is clean. Is it possible 30 year old thermostat is not fully opening? I ordered an NOS Stant 14068 on eBay today.

Dynomite · 08-24-2023

Quote:

Originally Posted by Young1

I am experiencing the same thing as OP. Never have before. All is clean. Is it possible 30 year old thermostat is not fully opening? I ordered an NOS Stant 14068 on eBay today.

Marc Haibeck suggested at one time the older Stants will deteriorate (Decrease in FUll Open Area) by up to 15% as they age. A thermostat with over 50k miles generally opens 5 degrees later and opens about 85%.

longhorns05 · 08-24-2023

Quote:

Originally Posted by Young1

I ordered an NOS Stant 14068 on eBay today.

I tried a Stant t-stat 3 yrs ago, it never worked right out of the box. The car consistently ran hot until I swapped it out. Especially being in FL, it might be a good idea to look into a lower temp t-stat from Marc or Corey

Young1 · 08-24-2023

Well, if Marc says it I believe it. I was only guessing but the Man knows. At 75k miles I am due for replacement. I will follow up after I install it.

longhorns05 · 08-24-2023

Quote:

Originally Posted by Prez1967

When I turn the A/C on, the car's water temp creeps up to 223-225.

Is this normal? or do I have to roll my sleeves up and dig in...

Have you checked to make sure both fans are running when this happens?

08-22-2023	#1
Prez1967 Join Date: Aug 2018 Location: Finksburg, MD Posts: 244	Temp goes from 200 to 225 when A/C is on I cant recall if this was the case since I bought my car but I recently noticed that when Im cruising around without A/C, the car is at a stead 200-202 degrees. When I turn the A/C on, the car's water temp creeps up to 223-225. Is this normal? or do I have to roll my sleeves up and dig in... __________________ 1994 #353 "Bluey"

08-22-2023	#2
Jagdpanzer Join Date: Apr 2007 Location: Northern VA Posts: 2,658	Re: Temp goes from 200 to 225 when A/C is on What radiator do you have installed? What temperature are the fans programmed to come on? Sent from my iPhone using ZR-1 Net Registry __________________ Phil Wasinger 1994 Torch Red ZR-1 WAZOO Member George Braml Intake

08-23-2023	#5
Prez1967 Join Date: Aug 2018 Location: Finksburg, MD Posts: 244	Re: Temp goes from 200 to 225 when A/C is on Got my stats mixed up. T-stat is either 160 or 180 (dont remember) fans are set to whatever Marc's standard set up is. Intake Air Temp? It was SUPER hot a couple weeks ago when I was driving around in heavy traffic and with the A/C off, the temperature was stable at 200 degrees. When I'd click on the A/C it would stabilize at 225. Same result when I was going highway speeds. It was considerably cooler the last time I drove the car had the same results. Im planning on driving the car tonight. Can check air temp tonight and report back __________________ 1994 #353 "Bluey"

08-23-2023	#6
Young1 Join Date: Sep 2016 Location: Ocala, FL Posts: 894	Re: Temp goes from 200 to 225 when A/C is on I am experiencing the same thing as OP. Never have before. All is clean. Is it possible 30 year old thermostat is not fully opening? I ordered an NOS Stant 14068 on eBay today. __________________ Steve Young 1991 ZR-1 Quasar Blue Metallic/Black #729 Second Owner 1991 ZR-1 Dark Red Metallic/Black #2040 SOLD 1990 ZR-1 Dark Red Metallic/Saddle #1670 SOLD Double your happiness.....complain half as much.

08-24-2023	#9
Young1 Join Date: Sep 2016 Location: Ocala, FL Posts: 894	Re: Temp goes from 200 to 225 when A/C is on Well, if Marc says it I believe it. I was only guessing but the Man knows. At 75k miles I am due for replacement. I will follow up after I install it. __________________ Steve Young 1991 ZR-1 Quasar Blue Metallic/Black #729 Second Owner 1991 ZR-1 Dark Red Metallic/Black #2040 SOLD 1990 ZR-1 Dark Red Metallic/Saddle #1670 SOLD Double your happiness.....complain half as much.