High temp. ???
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Racer
Joined: Feb 2003
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From: Ca
High temp. ???
Went to Tahoe last weekend for the show , and she was running over 200 most of the way up , hit 240 a couple times . Is this normal ? I have a new stock radiator . Do I need thicker all aluminum or what ? Engine is new also . How hot is too hot ? 
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Joined: Feb 2006
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From: Overland Park, everett Kansas, mass
Originally Posted by 87 covertible
Went to Tahoe last weekend for the show , and she was running over 200 most of the way up , hit 240 a couple times . Is this normal ? I have a new stock radiator . Do I need thicker all aluminum or what ? Engine is new also . How hot is too hot ?
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
While 200 can be typical for really hot weather, I would check the front of the radiator and the A/C condensor for debris. Junk in the front of these will cause a loss of airflow and that can result in higher coolant temps.
You can use a stream of water from a hose to flush out junk. Aim the water from behind the radiator and push it forward. You can find dirt, leaves, debris, plastic bags, small animals, Honda's and who knows what else clogging up the fins.
If evertthing is clean, than I would suspect a thermostat that is sticking or possibly a lower radiator hose collapsing. Did you replace the radiator hoses when the engine and radiator was done??
You can use a stream of water from a hose to flush out junk. Aim the water from behind the radiator and push it forward. You can find dirt, leaves, debris, plastic bags, small animals, Honda's and who knows what else clogging up the fins.
If evertthing is clean, than I would suspect a thermostat that is sticking or possibly a lower radiator hose collapsing. Did you replace the radiator hoses when the engine and radiator was done??
Burning Brakes
Joined: May 2006
Posts: 1,097
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From: Richfield Utah
From your question, you said you put a new radiator in it. I would suppose you cleaned the void between the radiator, and the condenser unit. So that leaves us with. Are the fans turning on properly? How fast and hard were you driving it? How is the coolant level? However, if it was hot and you were asending, sounds about right to me... Especially with an auto trans...
Pro
Joined: Jan 2004
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From: Syracuse Utah
200 sounds okay but 240 with a new (that means without 20 lbs of pebbles clogging it up) radiator sounds a little worrysome to me. Burp the system and check the operation of your fans. I would not expect a good system to go above 230 at freeway speeds regardless of the ascent.
Team Owner
Joined: May 2006
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
I would suggest putting a cooler thermostat in perhaps 180* for winter use ans 160* for summer use(this is what I do) seems to like it a lot. I also installed a new fan switch that comes off the side of the head(you'll need a 5/16" square drive to remove it, you might have to have a shop remove this as the square drive tool is not easily found!) the switch will come on at 180 approx and shut off at 167* you can get one with instructions from http://www.madvet.com/shop?frame=3.138.944
Thanks, Matt
Thanks, Matt
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Safety Car
Joined: Apr 2001
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From: Houston TX
I run a Dewitt, and am pleased with what it does for my '87 roadster. 
However, I think you may benefit from a thermostat swap to a Robertshaw with the (3) o.010" holes drilled around the base. Clean the area in front of the radiator and condensor as well as in between (take the upper shrould off for access). Also thoroughly flush the complete system (run the heater while you are doing this flush). Provided there are no surprises (i.e. serious "chunks coming out of the system, totally blocked radiator core, etc.) then refill with a fresh mix of coolant and water. Ensure that you top off the coolant system properly.
You should be back to running cool in no time.
Aaron
However, I think you may benefit from a thermostat swap to a Robertshaw with the (3) o.010" holes drilled around the base. Clean the area in front of the radiator and condensor as well as in between (take the upper shrould off for access). Also thoroughly flush the complete system (run the heater while you are doing this flush). Provided there are no surprises (i.e. serious "chunks coming out of the system, totally blocked radiator core, etc.) then refill with a fresh mix of coolant and water. Ensure that you top off the coolant system properly.
You should be back to running cool in no time.
Aaron
Drifting
Joined: Mar 2004
Posts: 1,500
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From: Mauldin sc
St. Jude Donor '05
Originally Posted by 87 covertible
Went to Tahoe last weekend for the show , and she was running over 200 most of the way up , hit 240 a couple times . Is this normal ? I have a new stock radiator . Do I need thicker all aluminum or what ? Engine is new also . How hot is too hot ?
Race Director
Joined: Sep 2000
Posts: 17,298
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From: The Top of Utah
Originally Posted by 87 covertible
I have a new stock radiator . Engine is new also . How hot is too hot ?
RACE ON!!!
Drifting
Joined: Mar 2004
Posts: 1,500
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From: Mauldin sc
St. Jude Donor '05
I have had my 87 for 20 yrs now and I have never seen temps higher than 230. Zero mods all original even to this day my temps at 65-70mph is 177 degrees. I would say there is something wrong with those temps , unless it had something to do with the high altitudes of the Summit " old stomping grounds "
or is this your usual temps ??
" old stomping grounds " or is this your usual temps ??
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by golfman2008
Zero mods all original even to this day my temps at 65-70mph is 177 degrees.
RACE ON!!!
Race Director
Joined: Sep 2000
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From: The Top of Utah
Originally Posted by rick lambert
I'd bet he has a 180 thermostat in it. From personal preference I'd pitch any 195 and replace it with a 180.
RACE ON!!!