93 LT-1 Running Hot
Thread Starter
Racer
Joined: Oct 2005
Posts: 430
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From: Marlow OK
93 LT-1 Running Hot
Temp guage reads 207. I think it has the 190 degree thermostat (which was replaced about 2 years ago). Car sat for a year while I was in Iraq. Have been driving about 60 miles/day, 2 days/week for about the past 3 months. Has 109K miles. Don't think radiator has ever been out and redone. Otherwise, all well w/this machine.
Last edited by 73737373; Oct 1, 2010 at 08:39 AM. Reason: Change Thread Subscription
Drifting
Joined: Jun 2010
Posts: 1,853
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From: Westerly RI
How does the coolant look? My first move would be a flush and refill, removing the knock sensors to drain the block. Depending on how much crud comes out, you could think about having the radiator cleaned.
Burning Brakes
Joined: Dec 2005
Posts: 819
Likes: 3
From: Flowery Branch Ga
The car sitting for a while could have caused some build up in the radiator. I would fush the cooling system and add new coolant with some water wetter. I had the same issues with my 93 when I bought it. Remember the LT1's run in the hotter range. Here in Ga. it was usually in the 220 range on average. 207 is not bad. Also check the front of the radiator for leaves ect..
Last edited by Sargevette; Oct 1, 2010 at 08:58 AM.
Thread Starter
Racer
Joined: Oct 2005
Posts: 430
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From: Marlow OK
I also have a 96 LT-4 and drove it a couple times this week and she sat hard on 190 degrees...same route, same time of the day. I'd expect the same from my 93 once this heating issue is rectified. Why would GM design a car calling for a 190 degree thermostat, yet the car runs hotter than that....a rhetorical question (no answer needed).
Team Owner
Joined: Dec 1999
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
IS the 207 an average temp or does it move up and down? The LT1's are designed to run anywhere from 195 to 210 or so depending on outside air temps, vehicle speed, and RPM.
Is the secondary fan coming on when it should? I think it should come on at 238. Turning the A/C on will start the secondary fan.
Check for debris in the front of the A/C condenser and the radiator. Get dirt and garbage in there and the loss of airflow will cause a rise in cooling temps.
A flush and re-fill can't hurt but I'll bet that either the 'stat is sticking or there is something blocking airflow thru the radiator.
Is the secondary fan coming on when it should? I think it should come on at 238. Turning the A/C on will start the secondary fan.
Check for debris in the front of the A/C condenser and the radiator. Get dirt and garbage in there and the loss of airflow will cause a rise in cooling temps.
A flush and re-fill can't hurt but I'll bet that either the 'stat is sticking or there is something blocking airflow thru the radiator.
Thread Starter
Racer
Joined: Oct 2005
Posts: 430
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From: Marlow OK
207-209 is the normal operating temp once the car has warmed up. Yes, the fans come on, but at the same operating range temps. The temp has never gotten as high as 238. I drive the car on the highway under 65 MPH.
I am inclined to think the same, that crud has built up in/around the fins on the radiator and a/c condensor and not allowing sufficient air to pass. Have a 91 Chev pickup that needs air or hi pressure water blown back thru the radiator about 1/year to clear the dust/dirt/bugs (rural Oklahoma) that build up. Problem w/the Corvette is that there is no easy way to access the radiator from the backside short of pulling the air cleaner assembly, the shroud and the electric fans....so, if you're I'm going to expend that much labor, why not just go 1 step further and pull the radiator and have it serviced or replaced? Nothin' is ever easy w/these cars, is it? I should've collected stamps!!
I am inclined to think the same, that crud has built up in/around the fins on the radiator and a/c condensor and not allowing sufficient air to pass. Have a 91 Chev pickup that needs air or hi pressure water blown back thru the radiator about 1/year to clear the dust/dirt/bugs (rural Oklahoma) that build up. Problem w/the Corvette is that there is no easy way to access the radiator from the backside short of pulling the air cleaner assembly, the shroud and the electric fans....so, if you're I'm going to expend that much labor, why not just go 1 step further and pull the radiator and have it serviced or replaced? Nothin' is ever easy w/these cars, is it? I should've collected stamps!!
Last edited by 73737373; Oct 1, 2010 at 09:56 AM. Reason: Needed to provide more info
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My primary fans come on at 228 degrees. You might have an air pocket trapped inside your cooling system.
With the engine cold, put a paper towel under your coolant bleed valve (on the throttle body and water pump inlet housing) then open the valve and add coolant until a steady stream seeps out.
Next, close the valve and refill until the system is at capacity. Start the engine and allow the car to reach operating temp.
Keep an eye on your coolant level for the next couple of days. My temp gauge reads 197-200 degrees at highway speeds, but will creep up to 205 degrees in traffic.
That's perfectly normal as the LT1's are designed to run hot for emissions purposes.
With the engine cold, put a paper towel under your coolant bleed valve (on the throttle body and water pump inlet housing) then open the valve and add coolant until a steady stream seeps out.
Next, close the valve and refill until the system is at capacity. Start the engine and allow the car to reach operating temp.
Keep an eye on your coolant level for the next couple of days. My temp gauge reads 197-200 degrees at highway speeds, but will creep up to 205 degrees in traffic.
That's perfectly normal as the LT1's are designed to run hot for emissions purposes.
Le Mans Master
Joined: Dec 2004
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From: Myrtle Beach SC
St. Jude Donor '05-'06
Before I changed my WP mine ran ~198 on the highway in the summer w/AC now it is 201-205 range I think the WP is slightly less efficient and there were no gaskets on the one I took off maybe better heat sink. With the AC off it runs 197 all day on the highway. I know my AC is draggin has a slight seal leak adding to the heat I am sure. With all that being said your temp is fine I would start worring when it starts going over 210 on a regular basis. In stop and go traffic it is normal to hit 210 once in a while as long as it drops back when moving.
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Before I changed my WP mine ran ~198 on the highway in the summer w/AC now it is 201-205 range I think the WP is slightly less efficient and there were no gaskets on the one I took off maybe better heat sink. With the AC off it runs 197 all day on the highway. I know my AC is draggin has a slight seal leak adding to the heat I am sure. With all that being said your temp is fine I would start worring when it starts going over 210 on a regular basis. In stop and go traffic it is normal to hit 210 once in a while as long as it drops back when moving.
From my local GM dealer, I also purchased one GM waterpump drive seal: 10217886; and two GM water pump O-rings 12553792.
Figured I might as well button the job down right while I was in there.
