overheating
Thread Starter
Cruising
Joined: Nov 2002
Posts: 14
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From: Waco Texas
overheating
My 91 'vette overheats in in the hot weather, when it's idle. Sometimes the fan's don't work. Isn't there something I canput on it to make the fans kick on??
Please help me.Thanks :blueangel:
Please help me.Thanks :blueangel:
Burning Brakes
Joined: Oct 2002
Posts: 835
Likes: 3
From: Water Winter Wonderland
Re: overheating (91VetteGirL)
Well, you are definitely going to need your fan or fans to turn on when the coolant temp gets up there. I think MidAmerica and/or Echlers have a manual fan switch you can install.
But another very common problem is the radiator getting full of junk. The C4 Corvette is a very efficient vacuum cleaner, traveling down the public roads sucking up all the light stuff - leaves, cottonwood fluff, dog hair, etc. and depositing the dirt onto your radiator. Everyone that I have heard of who removed their radiator (including me) was shocked at how clogged up it was.
:cheers: -Bill
[Modified by ELEVENS, 2:04 PM 6/3/2003]
But another very common problem is the radiator getting full of junk. The C4 Corvette is a very efficient vacuum cleaner, traveling down the public roads sucking up all the light stuff - leaves, cottonwood fluff, dog hair, etc. and depositing the dirt onto your radiator. Everyone that I have heard of who removed their radiator (including me) was shocked at how clogged up it was.
:cheers: -Bill
[Modified by ELEVENS, 2:04 PM 6/3/2003]
Le Mans Master
Joined: Jul 2002
Posts: 5,818
Likes: 2
From: Alive and well in Burlington NC
Re: overheating (91VetteGirL)
What temps are you seeing? An estimate is fine since you have the same analogs I do. A stock C4 will run ~238* in traffic before the main fan comes on. The general did this for a number of reasons, ie. emissions. If your radiator is clean, the coolant is good and green and your thermostat is not stuck there are a few ways to bring the temps down. Manual fan switch, programed chip, etc. If you are not seeing temps up around 250* or so it would be considered "normal".
Team Owner
Joined: Sep 2001
Posts: 62,137
Likes: 1,727
From: Athens AL
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Re: overheating (91VetteGirL)
The main fan should come on at 228F, is it not coming on at all? I would check the connections and especially the fan relay.
Overheating is a common problem for C4s, GM designed them to run hot to pass emissions, so temps in the 200-230 range are not abnormal.
The stock thermostat is 195, in TX i would definitely change it to a 160. Its about to get really hot down there, if its not terrible already.
Then, you MUST remove the radiator shroud and clean the space between the radiator and condensor, its blocking airflow and cleaning it tends to drop temps by 10-20F.
Only real permanent fix though is to buy a fan switch, from Ecklers or MidAmerica, wire it to the main fan so it will come on sooner. That will keep it from overheating.
Overheating is a common problem for C4s, GM designed them to run hot to pass emissions, so temps in the 200-230 range are not abnormal.
The stock thermostat is 195, in TX i would definitely change it to a 160. Its about to get really hot down there, if its not terrible already.
Then, you MUST remove the radiator shroud and clean the space between the radiator and condensor, its blocking airflow and cleaning it tends to drop temps by 10-20F.
Only real permanent fix though is to buy a fan switch, from Ecklers or MidAmerica, wire it to the main fan so it will come on sooner. That will keep it from overheating.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Re: overheating (91VetteGirL)
Cleaning the debris will help for sure.
In hot climates the automatic fan switch from MAD or Eckler's would be nice. They have one that works around your stock 195 deg stat or you can put in a lower temp stat and fan switch for even lower temps.
In hot climates the automatic fan switch from MAD or Eckler's would be nice. They have one that works around your stock 195 deg stat or you can put in a lower temp stat and fan switch for even lower temps.
Racer
Joined: Nov 2002
Posts: 471
Likes: 0
From: Queens NY
Re: overheating (91VetteGirL)
Regardless of how much crap is blocking your radiator, the fans are set to go on at a given temperature. The crap in the radiator will just help the car get there faster
If the fans aren't going on when they're supposed to, you have a different issue like a relay or maybe a temp sender
If you want to make them come on sooner, I believe either Summit or Jegs sells different senders that make them come on at different times. Also i'd do the thermostat
[Modified by CarAteMyMoney, 1:49 AM 6/4/2003]
If the fans aren't going on when they're supposed to, you have a different issue like a relay or maybe a temp sender
If you want to make them come on sooner, I believe either Summit or Jegs sells different senders that make them come on at different times. Also i'd do the thermostat
[Modified by CarAteMyMoney, 1:49 AM 6/4/2003]
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From: OBAMA IS HITLER
Re: overheating (vader86)
....The stock thermostat is 195, in TX i would definitely change it to a 160. Its about to get really hot down there, if its not terrible already.
Only real permanent fix though is to buy a fan switch, from Ecklers or MidAmerica, wire it to the main fan so it will come on sooner. That will keep it from overheating.
Only real permanent fix though is to buy a fan switch, from Ecklers or MidAmerica, wire it to the main fan so it will come on sooner. That will keep it from overheating.
Le Mans Master
Joined: Apr 2001
Posts: 7,410
Likes: 252
From: Little Elm TX
Re: overheating (bradvette)
First check the radiator for obstuctions.
Stuff like that doesn't help. I also just replaced my primary fan motor as it went out and my A/C blower motor bit the dust about 2-3 weeks later. I don't know how many miles you have, but I would say it isn't out of the question that the fan may be going out.
Stuff like that doesn't help. I also just replaced my primary fan motor as it went out and my A/C blower motor bit the dust about 2-3 weeks later. I don't know how many miles you have, but I would say it isn't out of the question that the fan may be going out.