How hot?
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How hot?
My grandson and I went for a nice ride this morning in my 86 coupe. We were in a state park with a 15 mph speed limit at about 75 degrees. My temperature was reading 227. I'm still getting used to my car so I don't know whats normal yet. When should I get concerned?
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From: Compound in the Grove, Ga.
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Completely normal that is around the stock temp for the first fan to cycle on, the second will come on around the 235 mark.
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
That temp is certainly within the normal temerature range, but I'm thinking that the fins and tubes in both the A/C condenser and radiator could very well be clogged up with dirt and debris. At the air temps and the speed mentioned, the coolant temps should be around 200 or maybe less. There's also a possibility of the cooling system being low on fluid and not having any coolant in the overflow bottle. A pressure cap may be failing, thermostat may not be opening for some reason, or even the lower radiator hose could be collapsing.
Other issues could be blockages in the radiator tubes. If the radiator is original it's entirely possible that the tubes in the radiator have become so thin from coolant passing thru them that they cannot transfer heat quickly enough.
It would be a good idea to check all of those things and possibly doing a coolant system service. Definitely check for the dirt and debris!!
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The auxiliary fan is located in front of the radiator. It is controlled by a coolant temperature switch in one of the cylinder heads (which one varies by year -- '86 is on driver's side).
227° is not really too high with the AC on.
As advised earlier, check for trash between the AC condenser and the radiator. It's easier to do that if you do this modification:
http://forums.corvetteforum.com/c4-t...post1587007676
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From: indy indiana
Those are reasons why, here are two things that you can do .I put 160 degree thermostat AND a bottle of wetter water (water wetter?). Seems to help. The wetter stuff cost around 15 bucks for a pint.I actually used Purple brand which was sitting next to wetter water at Summit Racing up Ohio way.
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From: Clifton Park, NY ............Clearwater, FL ... 85 Original Owner
Those are reasons why, here are two things that you can do .I put 160 degree thermostat AND a bottle of wetter water (water wetter?). Seems to help. The wetter stuff cost around 15 bucks for a pint.I actually used Purple brand which was sitting next to wetter water at Summit Racing up Ohio way.
This is my radiator a few years ago. Couldn't tell it was this bad until out. Runs much cooler now after cleaning
Last edited by Cruisinfanatic; Jun 1, 2014 at 11:05 AM.
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Cliff, thanks for the link. I will definitely do that. I had my son crawl under her last night. He said there are clumps of dirt hanging on the front of the A/C coil. I'm not sure how that got there, must be a gift from the previous owner. Just something else on my list of things to do.
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
C4's are referred to as "bottom breathers" in that all of the air for engine cooling, A/C operation and engine intake come in from behind the nose. So you can see why it would be easy to get debris and dirt up there and eventually you get large areas that block airflow.
You can use a stream of water from a garden hose to loosen up a lot of that stuff. Point the nozzle towards the front of the car from the back side of the radiator. You may first want to try using a vacuum to suck loose dirt out from the front side of the A/C condenser. Then lightly spray the condenser and let the water soak into the dirt. After a few minutes you can use the hose on the back side of the radiator.
You can use a stream of water from a garden hose to loosen up a lot of that stuff. Point the nozzle towards the front of the car from the back side of the radiator. You may first want to try using a vacuum to suck loose dirt out from the front side of the A/C condenser. Then lightly spray the condenser and let the water soak into the dirt. After a few minutes you can use the hose on the back side of the radiator.
