Need Info On Operating Temp for 1986 Vette

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Jun 30, 2002 | 03:22 PM

dmac

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From: Sturgeon Bay WI

Need Info On Operating Temp for 1986 Vette

Just bought a 1986 coupe with 30,000 miles on it, after parting with my 1981 last fall. I have noticed that my new 86 is running at about 200 to 223 degrees in traffic (outside temp about 80) and about 195 degrees on the highway. This seems high to me, as my 81 ran a pretty consistent 180 degrees. Can anyone tell me what temp this car should be running at? The fan is kicking in at about 200 degrees. One other thing, the power windows in my 81 moved up and down very, very rapidly, in the 86 they seem to take for ever to go up or down, is this normal ? Thanks for any help from experienced C-4 owners. DMac

Jun 30, 2002 | 04:22 PM

L98IROCZ89

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From: South River, NJ

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Re: Need Info On Operating Temp for 1986 Vette (dmac)

The L98 motor should have a 180 stat in it and run between 180 and 200. 220 is OK but any higher is really no good. The person who owned the car before you may have put a 195 stat in it accidentally. Start by changing the thermostat to a high flow 180 or a 160.

Jun 30, 2002 | 04:41 PM

Husker Vette

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From: Are you the bug or are you the windshield.....

Re: Need Info On Operating Temp for 1986 Vette (L98IROCZ89)

Actually, I think that the 86 came with 195 degree thermostat, which would explain the 195 at Highway speeds.....

Your car is doing pretty good, and not much more to do.... Your electric fan should kick on at 227 and back off at 212 (of course when the AC is on, it is running all the time).....

I wish my 86 ran at those temps......

Jun 30, 2002 | 04:48 PM

CFI-EFI

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Re: Need Info On Operating Temp for 1986 Vette (dmac)

There is nothing wrong with those temperatures. I thought my car was running awfully hot when I first bought it too. My fan came on at 225, stock. Seeing 235 wasn't unusal. Our cars have a 195* thermostat. Even though this is "normal", I was uncomfortable with these temps. I changed the fan controlling switch to turn my fan on at 205 and off at 195. Your's is computer controlled, but you are already there. I installed a 180* thermostat after trying a 160 and deciding that was too cool. Next (highly reccommended) I pulled the radiator and cleaned out the mud, sand, twigs, and birds nests that had accumulated, over the years, between the condensor and radiator. I added a bottle of "Water Wetter" and now I rarely see 190* at speed in 100*+ heat. Usually, it runs just over the thermostat at 182-183. The fan only comes on at low-low speeds, and the it never tops 207 as it starts cooling off with the fan. I don't know if this "ideal" or not, but it pleases me. Some, on here swear by the 160 thermostat. Good luck.

Jun 30, 2002 | 06:30 PM

vader86

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Re: Need Info On Operating Temp for 1986 Vette (dmac)

Your temps are normal, the 86 comes with a 195 degree tstat, but since you live in WI, i wouldnt go with less than a 180 stat if you decide to change it.

L98s are designed to run hot for emissions but the engine actually likes to run and makes good power at about 190. If youre concerned about overheating there are some things you can try to cool it down:

Clean the front of the radiator, it will be clogged up with dirt and debris.
Flush the old coolant out, and when you refill add a bottle of Water Wetter (WW usually drops it 10 degrees).
Change the tstat to a 180, not a 160 if you live in WI.
The main fan comes on at 225-230, aux fan about 235. You can have your chip reprogrammed to make the main come on sooner, and add a switch to make the aux fan come on sooner.

Jun 30, 2002 | 07:27 PM

dmac

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From: Sturgeon Bay WI

Re: Need Info On Operating Temp for 1986 Vette (dmac)

Thank you so much for the information. I feel relieved to know that it is not running too hot. I have a lot to learn about the C-4. I think I will change to 180 degree stat. just to make sure. There are so many differences between my 81 and this vette, but in time I will learn. Anyone have any thoughts on the power windows? They just seem so slow compared to the 81. Thanks again.

D Mac

Jun 30, 2002 | 09:11 PM

CG77VETTE

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From: Denville NJ

Re: Need Info On Operating Temp for 1986 Vette (dmac)

D Mac,

Your temps are very much within the norm for a stock L98. As far as the windows, the only way to speed them up is to convert to the newer style window regulator. It's on my list of things to do on my '86 but I'm waiting til something else goes in the doors so I can tackle both problems at once. Welcome to the C4 section and good luck with the '86.

Jun 30, 2002 | 10:39 PM

Juliet

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From: Maryland

Re: Need Info On Operating Temp for 1986 Vette (CG77VETTE)

Those temps are just like my '87 with new radiator and stock 195 thermostat. Freaked me out the first time they climbed up too compared with my '70 350/300Hp which runs consistently at 180-190.! :lol: ~Juliet