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Hello all, The wife and I went on a nice club cruise today in our 2002 convertible. We had a total of 16 Vettes including 1 C8...very nice...I love the motor under glass.
Anyway the weather was overcast but bright and not hot. The road was up and down and varying speeds. I noticed in some place the coolant temp gauge was running 220-230 F. No coolant overflowed and no hot motor odor happened so I wasn't concerned but just want to check it out. Maybe a new WP and t-stat are in order? On a better note the gas gauge seems to function now displaying amounts well under 1/2 full. I put about 4 cans of seafoam thru it over the past few months and it sat in storage for a while.Around town on shorter trips it runs about 200F
Before spending money on a water pump and T-stat, I would make sure the front of your condenser and radiator are clean. Our cars get air from the bottom and tend to suck up any and everything there is out there driving on the road. Shortly after I bought my 02 Z06 I looked under there and there was so much grass clippings and dirt clogged up on the front of the ac condenser. I ended up pulling the radiator and sprayed it down with simple green and back washed all the crud out the best I could. It made a big improvement on how much cooler the car ran by just pulling the rad and giving it a good cleaning. Only cost me a gallon of antifreeze and a gal of distilled water.
Before spending money on a water pump and T-stat, I would make sure the front of your condenser and radiator are clean. Our cars get air from the bottom and tend to suck up any and everything there is out there driving on the road. Shortly after I bought my 02 Z06 I looked under there and there was so much grass clippings and dirt clogged up on the front of the ac condenser. I ended up pulling the radiator and sprayed it down with simple green and back washed all the crud out the best I could. It made a big improvement on how much cooler the car ran by just pulling the rad and giving it a good cleaning. Only cost me a gallon of antifreeze and a gal of distilled water.
Thank you for your reply. I'll check it this week.
There is about a 1/2 or 1inch gap between condenser and radiator from bottom side under the car or pull the rad top support to get to it from top side. I made a tool from copper tubing, closed the end so no air exit and drilled 4 holes for air to exit and use air compress or water to clean the condenser area. Mine had a good amount of junk on front of condenser up at the top. Clean it off as best you can and it will help with temps.
Keep in mind these LS motors run hotter than the good old days. From the factory service manual: The low speed cooling fan is commanded on when the coolant temperature reaches 108°C (226°F). It is turned off if the coolant temperature lowers to 104°C (219°F). The high speed cooling fan is commanded on when the coolant temperature reaches 113°C (235°F). It is turned off if the coolant temperature lowers to 108°C (226°F). When the A/C is on and the coolant temperature reaches 85°C (185°F), the low speed cooling fan will be turned on at vehicle speeds less than 56 kPh (35 mph)
Before spending money on a water pump and T-stat, I would make sure the front of your condenser and radiator are clean. Our cars get air from the bottom and tend to suck up any and everything there is out there driving on the road. Shortly after I bought my 02 Z06 I looked under there and there was so much grass clippings and dirt clogged up on the front of the ac condenser. I ended up pulling the radiator and sprayed it down with simple green and back washed all the crud out the best I could. It made a big improvement on how much cooler the car ran by just pulling the rad and giving it a good cleaning. Only cost me a gallon of antifreeze and a gal of distilled water.
Originally Posted by bjones7131
There is about a 1/2 or 1inch gap between condenser and radiator from bottom side under the car or pull the rad top support to get to it from top side. I made a tool from copper tubing, closed the end so no air exit and drilled 4 holes for air to exit and use air compress or water to clean the condenser area. Mine had a good amount of junk on front of condenser up at the top. Clean it off as best you can and it will help with temps.
This is definitely the place to start and likely the cause of higher than normal temps. They are not extremely high but if it was my C5 I'd be looking at why. Cruising on a non-hot day my C5 runs about 200 degrees
Temps you posted are normal for a C5. Even when I don't need AC I leave it turned on and adjust the temperature on the HVAC. That keeps the fan running in traffic and the car runs cooler.
Did the clean out on my 03 too. Crawled under there blew it out with air and used a soft brush side to side.
Made sure the center section of the dam was placed and aiming correctly. Just did a drive on Route 66
2 weeks ago in 108-112 temps with AC on she ran about 194. Now in town she'll get up to 198-212. Cleaning
was a huge help.
I got caught in traffic a couple of years ago going to the Bloomington Gold show at the Indianapolis Motor Speedway and the temp on my 2002 got pretty up there. 230 or so. I know the fans switch on at pretty high temps, but it drove me crazy. I bought the fan control switch setup sold by Sac City Corvette and installed it. You can manually control one of the fans using the little microswitch mounted on the console. I know your situation is different since you were moving but I just wanted to make a comment that this little thing put me at ease. With all the construction and stupid accidents anymore, getting stuck on the interstate or somewhere when it is really hot made me nervous. I did check mine last winter when I replaced all the belts and hoses and found everything really clean and neat. My little car doesn't have a ton of miles though. Ken
If Hi-Temp is bothering you. Sac City Corvettes sell a Cool It V2 it is a manual on/off for you Hi Speed fan. Takes about 5-10 minute install. Works great during drive or after shut down
Talk to Chris @ Sac City Corvette
If Hi-Temp is bothering you. Sac City Corvettes sell a Cool It V2 it is a manual on/off for you Hi Speed fan. Takes about 5-10 minute install. Works great during drive or after shut down
Talk to Chris @ Sac City Corvette
I had this on my previous 01 and it worked great. About 120.00 I think.
Hello all, The wife and I went on a nice club cruise today in our 2002 convertible. We had a total of 16 Vettes including 1 C8...very nice...I love the motor under glass.
Anyway the weather was overcast but bright and not hot. The road was up and down and varying speeds. I noticed in some place the coolant temp gauge was running 220-230 F. No coolant overflowed and no hot motor odor happened so I wasn't concerned but just want to check it out. Maybe a new WP and t-stat are in order? On a better note the gas gauge seems to function now displaying amounts well under 1/2 full. I put about 4 cans of seafoam thru it over the past few months and it sat in storage for a while.Around town on shorter trips it runs about 200F
Yup those temps are perfectly normal for the stock c5
Hello all, The wife and I went on a nice club cruise today in our 2002 convertible. We had a total of 16 Vettes including 1 C8...very nice...I love the motor under glass.
Anyway the weather was overcast but bright and not hot. The road was up and down and varying speeds. I noticed in some place the coolant temp gauge was running 220-230 F. No coolant overflowed and no hot motor odor happened so I wasn't concerned but just want to check it out. Maybe a new WP and t-stat are in order? On a better note the gas gauge seems to function now displaying amounts well under 1/2 full. I put about 4 cans of seafoam thru it over the past few months and it sat in storage for a while.Around town on shorter trips it runs about 200F
That temp range is perfectly normal on a factory engine C5. It was designed that way.
If Hi-Temp is bothering you. Sac City Corvettes sell a Cool It V2 it is a manual on/off for you Hi Speed fan. Takes about 5-10 minute install. Works great during drive or after shut down
Talk to Chris @ Sac City Corvette
I too had one of those on my 98 which is now sold . She had a 383 that was supercharged and boy, she got hot. The fan control helped keeping the temps down.
On my current supercharged C5, I had a technician change my factory fan settings to much lower temps.
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The temps you were seeing are not abnormally high as the LS motors do run hotter than what you may be used to. Do the radiator area clean out and see if the temps come down.