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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Engine Running Hot?

  • Thread starter Thread starter Stang_1973
  • Start date Start date Apr 17, 2004

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Apr 17, 2004
#1
  • Apr 17, 2004
  • #1
Well it has been a while now that I had the engine rebuilt. After about a month, one day the Temp light came on and so I checked the coolant and it needed some so I poured some in the radiator. However, now when I go to turn on the car in the morning the temp light gradually starts to brighten until its bright red and then never goes away. This has only started happening after thte first time it came on. I have also noticed that the engine doesn't feel like it has alot of kick as it used to when you nail it. Can anybody help me? Why wont the temp light go off? Why would the engine be running hot?

The thermostat is a 160. The fan has five blades, and the radiator is pretty big. The guy who did the rebuild said that I didnt need a fan shroud.
 

rbohm

Founding Member
Apr 12, 2002
6,698
550
204
tucson,az
Apr 18, 2004
#2
  • Apr 18, 2004
  • #2
first you need a fan shroud. second what condition is the rad in? what timing are you running? is the engine losing coolant?
 

87gn2

New Member
Apr 17, 2004
101
0
0
Apr 18, 2004
#3
  • Apr 18, 2004
  • #3
It's bored .040 over for one, the fan may not be all that great, your radiator may need to be flushed, and you do probably need a fan shroud, especially in San Antonio.
 
R

Ronstang

New Member
Apr 4, 2004
1,294
0
0
Houston Texas
Apr 18, 2004
#4
  • Apr 18, 2004
  • #4
Some 302s just can't handle a .040 overbore but you can't be sure of that so it may be time to upgrade to an aluminu radiator. I'm in Texas too and that is almost a must down here for these old cars to be truly streetable without worries. Electric fans are a real help too. Have you checked your timing, if it slipped and it retarded then that would explain the heat and the sluggishness.
 
S

sixtyfive

Member
Jan 9, 2004
157
0
16
Apr 18, 2004
#5
  • Apr 18, 2004
  • #5
i have a .040 over on my 289 with a 160 degree tstat, dinky ass radiator, flex fan, no fan shrowd, and dont need one

i never get overheated tho
 
R

Ronstang

New Member
Apr 4, 2004
1,294
0
0
Houston Texas
Apr 18, 2004
#6
  • Apr 18, 2004
  • #6
sixtyfive,

I said SOME 302s, not all. Some of the later blocks were thinner and it is always good to sonic check first to determine max overbore.
 

Stang_1973

Founding Member
Jul 13, 2001
565
9
38
San Antonio, Tx.
Apr 19, 2004
#7
  • Apr 19, 2004
  • #7
Okay, So where can I get an Aluminum Radiator? the one I have now is only about 2 years old.

Oh, I saw some stuff Called "40 Below" It supposed to drop engine temperature by like 40 degrees but costs like 50 bucks. Any body ever used it? There is also this thing you can put on the oil filter that acts like a heat sink and help cool the oil. Allegedly drops engine temperature up to like 30 degrees. Any body used that?
 
J

jesserose17

New Member
Aug 21, 2003
219
0
0
Southern CA
Apr 19, 2004
#8
  • Apr 19, 2004
  • #8
I would check the automatic transmission and make sure it's not slipping. I would check the timing as rbohm and Ronstang suggested earlier.

I have 160 thermostat on my '68 302, no shroud - it doesn't overheat at all in Mojave Desert.
 

Tubo(2-bo)

Member
Mar 25, 2004
279
0
16
Ft Walton Beach FL.
Apr 19, 2004
#9
  • Apr 19, 2004
  • #9
Get an AFCO 80100FN you dont need to spend big$$ to stay cool.22" wide AFCO $179.00
 

65fastback2+2

New Member
Aug 4, 2003
1,229
0
0
Louisville, KY
Apr 19, 2004
#10
  • Apr 19, 2004
  • #10
you just need a 180 t-stat, new rad, and a 6 blade fan and a new waterpump prolly and you'll be ready to rock.
 

69 302/351c

Founding Member
May 29, 2001
1,147
0
36
Walkertown NC, originally Western Mass
Apr 19, 2004
#11
  • Apr 19, 2004
  • #11
How hot is "hot"? Do you have a gage other than the warning light? Might have a bad sender.
 
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