Running Hot

sd88supra · 03-02-2008, 12:03 AM

I had the same problem, but I did the following and it went away:

- Check the headgasket and make sure its ok. Running with a hot engine will increase your chance of blowing the headgasket.

- "burp" the system and top it off just how others have described.

- Look for any pinched or damaged hoses. If there's pressure leaking it won't allow the coolant to flow efficiently. If a hose is pinched it can cause the pressure to rise and your cap might not be able to hold it, and you'll lose coolant.

- get a new radiator cap from Toyota. Aftermarket caps usually fall between "accepted" ranges which sometimes aren't so acceptable, especially with Japan using the metric system and the US still living in the dark ages when making measurements. Once I got a new cap from Toyota my coolant loss stopped (I was afraid it was the headgasket!).

- you might not want to do this if you just replaced the fan clutch, but electric fans cool much more efficiently than fan clutches, especially during hot weather. They take some load off your engine as well. You don't have a turbo, so a $130 electric fan will do just fine, and your engine will thank you for it.

Hope this helps.

sd88supra · 03-02-2008, 12:10 AM

I forgot, it boils after you turn off the car because there's no more air flowing onto the engine nor is there coolant flow, so the coolant (and engine as well) heats up. A minute after turning the car off, put the key in the open position (but don't start the engine) and you'll see that the temp gauge will have gone up. Not a good thing. Your coolant should never boil.

Benesesso · 03-02-2008, 01:22 AM

I've had this problem with both of my turbo Supras. I found a radiator shop that built me a couple of 3 row radiators. They helped, but the cars still run hot in the Phoenix summers. I changed the fan in the 1990 to a direct-drive stainless steel flex fan, and that helped, but it's a bit noisy.

In the summer, at ~110+ deg., both cars get up to ~220-230, on accurate gages, and the faster I drive the hotter they get. I run 50% antifreeze to keep the boiling point high. Both cars have good head gaskets.

I am convinced that Toyota screwed up and should have provided for a lot more airflow thru the rad.

sd88supra · 03-02-2008, 06:47 AM

^You should ask mrnickeleye about keeping your turbos cool. He lives in the desert as well and made some modifications to his N/A to keep it running cool, and they might help your turbos. Only I can't remember exactly what he did, but it had to do with cutting something out to increase the hot air flowing out.

mkiiisupra · 03-02-2008, 12:16 PM

The rubber seal that runs along the back of the engine bay above the firewall.... I know he removed that. it helps some heat escape through there.

Also make sure ur radiator cap is in good condition

supramacist · 05-30-2008, 06:41 PM

Quote:

Originally Posted by Benesesso

I've had this problem with both of my turbo Supras. I found a radiator shop that built me a couple of 3 row radiators. They helped, but the cars still run hot in the Phoenix summers. I changed the fan in the 1990 to a direct-drive stainless steel flex fan, and that helped, but it's a bit noisy.

In the summer, at ~110+ deg., both cars get up to ~220-230, on accurate gages, and the faster I drive the hotter they get. I run 50% antifreeze to keep the boiling point high. Both cars have good head gaskets.

I am convinced that Toyota screwed up and should have provided for a lot more airflow thru the rad.

Do an ac delete and get rid of the condensor blocking the radiator.

SC: Is this the same mechanic that unplugged your coolant sensor??
If it is. Find a new one or start gearing up to get dirty. Because if this guy didn't know about the sensor. You don't want him near the internals.
This is your car not a guinnea pig.

CyFi6 · 05-31-2008, 01:31 AM

a new engine is going to be just as costly, if not more, and probably will blow a head gasket within a short time if its on the original gasket

Benesesso · 05-31-2008, 03:09 AM

>"Do an ac delete and get rid of the condensor blocking the radiator."<

Except that I live near Phoenix, and the days may not get below 100+ until October----.

dj7mge · 06-01-2008, 12:11 AM

rebuild what you have use a stronger gasket and try some water wetter it works really good for about 3months my dad uses it in his drag car dropped his operating temp from 220 to 180-200

JPJ · 06-03-2008, 03:21 PM

Quote:

Originally Posted by supramacist

Do an ac delete and get rid of the condensor blocking the radiator.

SC: Is this the same mechanic that unplugged your coolant sensor??
If it is. Find a new one or start gearing up to get dirty. Because if this guy didn't know about the sensor. You don't want him near the internals.
This is your car not a guinnea pig.

Exactly!!!
The fact that your mechanic did this leaves little room for doubting the fact that he is indeed a moron.

03-02-2008, 12:03 AM	#1
sd88supra 3" Exhaust Join Date: Oct 2005 Location: San Diego, Ca Posts: 190	I had the same problem, but I did the following and it went away: - Check the headgasket and make sure its ok. Running with a hot engine will increase your chance of blowing the headgasket. - "burp" the system and top it off just how others have described. - Look for any pinched or damaged hoses. If there's pressure leaking it won't allow the coolant to flow efficiently. If a hose is pinched it can cause the pressure to rise and your cap might not be able to hold it, and you'll lose coolant. - get a new radiator cap from Toyota. Aftermarket caps usually fall between "accepted" ranges which sometimes aren't so acceptable, especially with Japan using the metric system and the US still living in the dark ages when making measurements. Once I got a new cap from Toyota my coolant loss stopped (I was afraid it was the headgasket!). - you might not want to do this if you just replaced the fan clutch, but electric fans cool much more efficiently than fan clutches, especially during hot weather. They take some load off your engine as well. You don't have a turbo, so a $130 electric fan will do just fine, and your engine will thank you for it. Hope this helps. __________________ -1987 5 spd N/A with TEMS: low miles! All stock with the exception of electric fans and an '89 front bumper, Yokohama 225/50/16 with stock rims. It's a mess and in the garage. -1987 5 spd Turbo with TEMS: miss-matched tires, needs lots of work, but it runs! Project car. -1988 N/A auto targa: all stock except 18" rims with Falken 265/35/18 in rear and 225/35/18 in front; daily driver.

03-02-2008, 12:10 AM	#2
sd88supra 3" Exhaust Join Date: Oct 2005 Location: San Diego, Ca Posts: 190	I forgot, it boils after you turn off the car because there's no more air flowing onto the engine nor is there coolant flow, so the coolant (and engine as well) heats up. A minute after turning the car off, put the key in the open position (but don't start the engine) and you'll see that the temp gauge will have gone up. Not a good thing. Your coolant should never boil. __________________ -1987 5 spd N/A with TEMS: low miles! All stock with the exception of electric fans and an '89 front bumper, Yokohama 225/50/16 with stock rims. It's a mess and in the garage. -1987 5 spd Turbo with TEMS: miss-matched tires, needs lots of work, but it runs! Project car. -1988 N/A auto targa: all stock except 18" rims with Falken 265/35/18 in rear and 225/35/18 in front; daily driver.

03-02-2008, 01:22 AM	#3
Benesesso 3" Exhaust Join Date: Nov 2005 Location: Phoenix, AZ Posts: 145	I've had this problem with both of my turbo Supras. I found a radiator shop that built me a couple of 3 row radiators. They helped, but the cars still run hot in the Phoenix summers. I changed the fan in the 1990 to a direct-drive stainless steel flex fan, and that helped, but it's a bit noisy. In the summer, at ~110+ deg., both cars get up to ~220-230, on accurate gages, and the faster I drive the hotter they get. I run 50% antifreeze to keep the boiling point high. Both cars have good head gaskets. I am convinced that Toyota screwed up and should have provided for a lot more airflow thru the rad. __________________ "You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein 1988 and 1990 Turbo Supras

03-02-2008, 06:47 AM	#4
sd88supra 3" Exhaust Join Date: Oct 2005 Location: San Diego, Ca Posts: 190	^You should ask mrnickeleye about keeping your turbos cool. He lives in the desert as well and made some modifications to his N/A to keep it running cool, and they might help your turbos. Only I can't remember exactly what he did, but it had to do with cutting something out to increase the hot air flowing out. __________________ -1987 5 spd N/A with TEMS: low miles! All stock with the exception of electric fans and an '89 front bumper, Yokohama 225/50/16 with stock rims. It's a mess and in the garage. -1987 5 spd Turbo with TEMS: miss-matched tires, needs lots of work, but it runs! Project car. -1988 N/A auto targa: all stock except 18" rims with Falken 265/35/18 in rear and 225/35/18 in front; daily driver.

03-02-2008, 12:16 PM	#5
mkiiisupra Lexus & 550's Join Date: Sep 2007 Location: Las Vegas, NV Posts: 570 Blog Entries: 1	The rubber seal that runs along the back of the engine bay above the firewall.... I know he removed that. it helps some heat escape through there. Also make sure ur radiator cap is in good condition __________________ 1990 Toyota Supra Turbo A/T ------------------------------------------------ Questions about oil? take a look http://www.supramania.com/aehaas/

05-31-2008, 01:31 AM	#7
CyFi6 3" Exhaust Join Date: Oct 2007 Location: SLO Posts: 234	a new engine is going to be just as costly, if not more, and probably will blow a head gasket within a short time if its on the original gasket

05-31-2008, 03:09 AM	#8
Benesesso 3" Exhaust Join Date: Nov 2005 Location: Phoenix, AZ Posts: 145	>"Do an ac delete and get rid of the condensor blocking the radiator."< Except that I live near Phoenix, and the days may not get below 100+ until October----. __________________ "You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein 1988 and 1990 Turbo Supras

06-01-2008, 12:11 AM	#9
dj7mge Stock Join Date: Mar 2008 Location: milwaukee,WI Posts: 18	rebuild what you have use a stronger gasket and try some water wetter it works really good for about 3months my dad uses it in his drag car dropped his operating temp from 220 to 180-200

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