[torn1965]

Hi to all vette owners ,Its been a while since I visited smokin vette, Had a great visit to the US in september and got to the Corvette funfest in Effingham, ILL and the Corvette National Museum in Bowling Green. Anyhow finally got vette on the road but as normal I have some issues 1. Excessive heat coming through center air vents even though the hot water to heat core is shut off with a manual valve and air diverter flap is in the cold position. 2 My owners manual says that the normal operating temperature is around 230f . This seems to high ? Any help welcome. Regards Torn

[fishslayer143@yahoo.com]

if your heater hose is closed with a shut-off then the heat is probably engine heat thru holes in firewall or the blower/evaporator housing ..... 230*F is not normal.. it should stay between 190*F and 210*F ... if its running that high, check your cooling fan clutch ..

[75 targa]

Hi Ian from south australia i had same problem and found on mine it was the seals around the vent flaps .i pulled out whole dash and did all vent seals and put new heat sheild on fire wall . if u contact me ianwhite20@gmail.com can go through what i did.
but these blokes on this site probally no more than me

[toobroketoretire]

There is supposed to be a seal along the rear of your hood. If that seal is missing a good portion of the engine's heat will escape thru the rear and get sucked into the plenum intake; raising interior temperatures considerably.

[torn1965]

Thanks for the help guys, Fishslayer , I run twin thermo fans as the factory fan and shroud was missing when I bought the car. I have had the dash and heater box out Ian when I replaced heater core and resealed but will look into it again . Toobroke , you could be on the money as that seal was replaced but yesterday I had a look and it appears to not be touching the firewall edge when hood is shut. I still only have the right side locking pin in place due to alignment issues with the left side.(looks like more hood adjustment is needed) My vet has a/c does it get no outside air intake when set on a/c max as my owners manual says? What do you think about the owners manual stating 230f as normal operating temp Toobroke? Regards torn

[toobroketoretire]

Originally Posted by torn1965

Thanks for the help guys, Fishslayer , I run twin thermo fans as the factory fan and shroud was missing when I bought the car. I have had the dash and heater box out Ian when I replaced heater core and resealed but will look into it again . Toobroke , you could be on the money as that seal was replaced but yesterday I had a look and it appears to not be touching the firewall edge when hood is shut. I still only have the right side locking pin in place due to alignment issues with the left side.(looks like more hood adjustment is needed) My vet has a/c does it get no outside air intake when set on a/c max as my owners manual says? What do you think about the owners manual stating 230f as normal operating temp Toobroke? Regards torn

As far as I know it wasn't until 1984 when they started running higher temperatures and that was because of their pitiful 2-tube radiators and electric fan. For the price of a new shroud, fan clutch, and 7-blade fan I would go back to the stock fan setup. The twin electric fans puts a substantial load on your alternator. To deal with the increased amperage demands the '84's came with the larger 15-SI 70 amp alternators then went to an even larger alternator the following year.

[toobroketoretire]

I have a 'big-block '71 with an aftermarket L-88 hood. Seeing the possibility of easily removing heat I cut the rear of the hood open; giving it 40 square inches of breathing area. During this last summer I checked my underhood temperature one day when it was 105 degrees with my A/C on and was astonished to find it was only 200 degrees after returning from a 200 mile trip.

[fishslayer143@yahoo.com]

Originally Posted by torn1965

Thanks for the help guys, Fishslayer , I run twin thermo fans as the factory fan and shroud was missing when I bought the car. I have had the dash and heater box out Ian when I replaced heater core and resealed but will look into it again . Toobroke , you could be on the money as that seal was replaced but yesterday I had a look and it appears to not be touching the firewall edge when hood is shut. I still only have the right side locking pin in place due to alignment issues with the left side.(looks like more hood adjustment is needed) My vet has a/c does it get no outside air intake when set on a/c max as my owners manual says? What do you think about the owners manual stating 230f as normal operating temp Toobroke? Regards torn

it doesn t get outside air on max.. the electric fans may be your high temp problem if you are in a very hot climate.. we have several members in south Florida that have given up on the electrics and gone back to mechanical fans ...the front of a C3 is too restrictive at hiway speeds.. do you have the lower frt spoiler on the car? http://www.ecklerscorvette.com/corve...1973-1979.html it is needed to direct air up into radiator ..also the seals on top of radiator are necessary too.

[torn1965]

I have a lower front spoiler on the way from the US , Hope that will help on the highway , Interesting that the Florida people went back to the mechanical set up . That may happen yet, Radiator and condensor have seals all round.

[fishslayer143@yahoo.com]

the lower spoiler will help on the hiway...the electric fans don t seem to be effective in really hot areas on the C3 s .. in moderate or cool climates they do fine... some have tried wiring both fans to run continuosly ..