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Underhood heat problems

  • Thread starter Thread starter artbillingsley
  • Start date Start date Oct 19, 2004
A

artbillingsley

New Member
Mar 4, 2003
10
0
0
Lafayette, LA
Oct 19, 2004
#1
  • Oct 19, 2004
  • #1
I have a 66 coupe that was originally an six-banger. When I initially restored the car, I restored it as a six cylinder. Recently I swapped to a 302 V-8 with the appropriate suspension and drivetrain upgrades. I now have an underhood heat problem. The engine temp with air condictioning runs at around 210 degrees (city traffic and more than 5 miles travelled). I have an electric fan with about 1800 cfm output. I notice at these operating temps that most components under the hood get to hot to handle and I have bogging problems when trying to accelerate. Also the engine runs poorly when I try to restart the engine if I don't allow it to cool down. I've put in larger fuel lines with no effect and made sure I have no contact with the exhaust system. I left on the rubber seal that runs along the top of the radiator on sixes. Should I remove it? I have a non-functional hood scope like the 66 GT's. Should I drill some holes thru the hood to make it partically functiional? Any suggestions are welcome. Thanks
 

65fastback2+2

New Member
Aug 4, 2003
1,229
0
0
Louisville, KY
Oct 19, 2004
#2
  • Oct 19, 2004
  • #2
you are in LA, my guess would be your radiator is too small. I run a 4 row copper dessert cooler. Mine has hit 230 before, but it has never bogged or died.
 
N

nds03

New Member
Jul 21, 2004
166
0
0
Oct 19, 2004
#3
  • Oct 19, 2004
  • #3
i got the same radiator, i live in florida and it works. it only gets hot sitting in traffic
 

blue66tang

Founding Member
Jan 20, 2001
1,092
0
0
Medford, OR
Oct 20, 2004
#4
  • Oct 20, 2004
  • #4
I would try putting a bigger fan in it. 1800cfm is kinda small for V8s, or switch to a belt fan. About the restarting thing. Hold the gas peddle to the floor and crank it till it starts, do not! pump the throttle. My guess is the reason it starts is because fuel is leaking down the carb when it it off and filling the intake. So when you hold the throttle wide open, it is letting in the extra air to lean it back down. Worked everytime on my old holley i used to have.
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Oct 20, 2004
#5
  • Oct 20, 2004
  • #5
Most heating problems will disappear using a larger radiator. If possible move up to aluminum. Overheating seems to be universal problem when upgrading engines on the early models.

HistoricMustang
www.historicmustang.com/tech.html
 
S

ssppiitt

New Member
Apr 8, 2003
206
0
0
Mountain View, Ca.
Oct 20, 2004
#6
  • Oct 20, 2004
  • #6
You may want to test your radiator cap to see if it is holding pressure. If it seems suspect replace it. Also check your thermostat to make sure it is working properly.
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Oct 20, 2004
#7
  • Oct 20, 2004
  • #7
Good point on the radiator cap! You could have a problem with the hood hitting and pressing down the cap. Been there and done that!

HistoricMustang
www.historicmustang.com/tech.html
 
S

steel1212

Active Member
Jun 24, 2004
1,180
0
36
Frankfort, Ky
Oct 21, 2004
#8
  • Oct 21, 2004
  • #8
I did the 6 banger to 302 recently and switched to a OEM 3 core radiator but I have a flexalite belt fan and march pulleys. During came burn in we had it at 2500 rpms for a half hour and the temp gauge never got pass half way, 66 gauges. I would check your thermostate or maybe get a bigger fan like already suggested. I know my fan will blow everything off the side of the car if the hood is up
 
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