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302 overheating???

  • Thread starter Thread starter carlton88444
  • Start date Start date Aug 6, 2010
C

carlton88444

New Member
Mar 1, 2010
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Aug 6, 2010
#1
  • Aug 6, 2010
  • #1
Ive got a 66 mustang with two barrel carb 302, im not sure of the year as i was not the one who did the swap but my car seems to be overheating. As soon as my temperature gauge gets up to 200 degrees my engine will shut off and i wont be able to start it back up again until it cools off a bit, it will turn over but it just wont run.
Ive installed a fan shroud and that helped but only increased the time it took to overheat, ive installed a new radiator and fan blade but it made no difference.
im thinking its the timing because its advanced about 25 to 30 degrees and should be around 10 but everytime i try to retard it, it starts to backfire, make weird noises, and sometimes takes longer to start or even not at all.

Anyone have any ideas as to why im over heating or why i cant retard the timing. Thanks, any help is appreciated!!!
 

mustangmutt

Member
Aug 2, 2010
339
6
18
El Paso, TX
Aug 6, 2010
#2
  • Aug 6, 2010
  • #2
200 is not overheated. 200 is practically normal. 250 is pushing borderline overheating. Basically if it overheats while idle or in slow traffic its an airflow problem. If it overheats while driving on the highway its a water flow problem. Is it boiling over, or pushing coolant out of the over flow? As far as the timing goes, it sounds like the balancer might be wrong or the pointer on the front cover. Early engines with the lower rad hose on the driver side had the pointer on the passenger side and newer engines with the lower rad hose on the driver side had the pointer on the passenger side. It is possible they put the 289 front cover on with the 302 balancer.
 
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carlton88444

New Member
Mar 1, 2010
3
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Aug 8, 2010
#3
  • Aug 8, 2010
  • #3
thanks, and yeah it does tend to overflow a little, as for the radiator its the one where both of the hoses are on the passenger side.
 

Realmongo

I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
2,468
86
99
Western Mass
Aug 8, 2010
#4
  • Aug 8, 2010
  • #4
Considering you probably have a 195 degree thermostat, it sounds more like a case of fuel line vapor lock that is shutting your engine down.
 

PoppyMod

Member
Jun 27, 2010
617
6
19
Severna Park, MD
Aug 9, 2010
#5
  • Aug 9, 2010
  • #5
+ 1 on the vapor lock thought. You might investigate adding a spacer between the intake and carb. The thicker the better, as long as you contact the hood. As mentioned your temps, don't appear all that high, actually, quite normal on average. I run about 195-200 on a 90+ day.
I have a 1/2 spacer and all of my fuel lines are away from the engine. An electric fuel pump helps, as well.
Good Luck!
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Aug 9, 2010
#6
  • Aug 9, 2010
  • #6
Your timing may be off due to a slipped outer ring on the balancer. Get the #1 Piston at TDC on the firing stroke and see where the timing mark is in relation to the pointer. While I agree that 200 isn't hot, the problem can also stem from many other things as well, like backwards head gaskets.
 
6

68RCodeConv

New Member
Oct 2, 2003
345
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0
Houston, TX
Aug 13, 2010
#7
  • Aug 13, 2010
  • #7
Are you unhooking the vacuum advance when checking the timing?
 
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