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Anyone had this problem?...

  • Thread starter Thread starter 19Nathen66
  • Start date Start date Apr 1, 2006
1

19Nathen66

New Member
Mar 22, 2006
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Apr 1, 2006
#1
  • Apr 1, 2006
  • #1
Why is my temp gage reading that my motor is overheating when I have plenty of coolant, an ok radiator, and I blast my heat? Also I noticed that it reads really high whenever I turn the car on after driving it....then after about 10 mins, the gage reads about halfway. I dont think its my thermostat cuz there is overflow from my radiator, so I know that my gage is right, and the motor is infact over heating! Anyone ever had this problem b4?
 
C

chemeng

New Member
Feb 21, 2004
93
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Louisville, KY
Apr 1, 2006
#2
  • Apr 1, 2006
  • #2
Yup, when you turn the motor off the heat collects at the top of the engine. Coincidentally that is where the temp sending unit is. After you drive it for 10 minutes the coolant circulates and the gauge will drop down. Had the exact same problem, tried everything including new radiator, 6 blade fan and different temperature thermostats. One day a freeze plug starting leaking (of course it was the one behind the motor mount). When I changed it I pulled some crap, looked like corroded pieces of metal from behind the plug. Finally decided it was impeding my coolant flow, if one freeze plug had crap behind it, all of them probably do. Said to heck with it and ordered a new engine. I would pull a freeze plug, run a magnet in there and see if you pull anything out. Mike
 
T

ttoney

Member
Sep 12, 2005
195
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16
Denver
Apr 1, 2006
#3
  • Apr 1, 2006
  • #3
Yeah, you might try a cooling system flush.
 

1320stang

Founding Member
Nov 13, 1998
4,329
23
89
Edmond, Oklahoma
Apr 1, 2006
#4
  • Apr 1, 2006
  • #4
and take the radiator to a shop and have it rodded out.
 

Tubo(2-bo)

Member
Mar 25, 2004
279
0
16
Ft Walton Beach FL.
Apr 1, 2006
#5
  • Apr 1, 2006
  • #5
The 65-66 radiators are too small and notorious for over heating. When I converted to EFI, part of the improvement was using to a cross flow 26" aluminum radiator. A 24"would do well, as the 26" is probably overkill. But the previous system had me chasing an overheating problem, that was never really solved, using the engine I had then.
 

Cobain03

Active Member
Aug 27, 2003
996
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36
Lexington, Ky
Apr 1, 2006
#6
  • Apr 1, 2006
  • #6
when you drive, the car, turn it off, and then look at the gauge 10 minutes later its hotter. thats called Latent Heat i believe.

i had cooling problems last summer as well. the previous owner switched my radiator for a differerent radiator and it still overheated. i was also using a "flex fan" which didnt help. i ended up adding an electric fan to help.
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Apr 1, 2006
#7
  • Apr 1, 2006
  • #7
If you're relying on the factory in dash gauge, that's the first mistake you've made here. Get a quality Mechanical gauge then tell us what it's doing.
 

1320stang

Founding Member
Nov 13, 1998
4,329
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89
Edmond, Oklahoma
Apr 1, 2006
#8
  • Apr 1, 2006
  • #8
Tubo3 said:
The 65-66 radiators are too small and notorious for over heating.
Click to expand...

I think that the above statement is false. My '65 coupe with a A-code, A/C and no shroud with the factory fan never overheated. It's all about proper maintenance. I've been looking on the 5.0 board lately, seems like a lot of the guys over there are young and just like to throw money at problems. First figure out the problem and see what it takes to fix it. There's nothing wrong with an aluminum radiator, but spending coin on that over something else you might need worse is senseless. Granted, if you have coin to just throw at it, go ahead I guess.
 

LMan

Founding Member
Aug 10, 2002
1,246
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0
Mom's basement
Apr 1, 2006
#9
  • Apr 1, 2006
  • #9
D-H is right. You cant make any judgements on the factory setup. Get a real gauge and see what its doing
 

HookandLadder

Founding Member
Feb 17, 2001
261
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17
St Louis
Apr 2, 2006
#10
  • Apr 2, 2006
  • #10
One word to help with the cooling........stock or modified.....SHROUD! Get it...use it........and the temp will go down.
 

69Rcode_Mach1

Active Member
Apr 20, 2004
1,473
1
37
Salt Lake City, Utah
Apr 2, 2006
#11
  • Apr 2, 2006
  • #11
My guage did it too. It was halfway across, but then when I shut it off then went to start the car again later the guage would max out. Those dummy guages are useless, I will agree with D. Hearne and recommend a mechanical guage also. A shroud will help a good deal. One thing that I noticed made a huge difference on my car, was switching to ceramic coated headers as opposed to iron manifolds. The cars temp was seriously reduced so much I couldn't believe it, and then it also added power to the car. Gives you an excuse to build for some fun.
 

MustangMatt1966

New Member
Mar 11, 2004
1,004
1
0
Orlando Fl.
Apr 2, 2006
#12
  • Apr 2, 2006
  • #12
HookandLadder said:
One word to help with the cooling........stock or modified.....SHROUD! Get it...use it........and the temp will go down.
Click to expand...


i agree 100% the shroud will help a bunch, i have a factory radiator, electric fan, and shroud all needed to cool down the engine..works fine, stays right about 180
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Apr 2, 2006
#13
  • Apr 2, 2006
  • #13
D.hearn and 1320 are on the mark. STOP throwing parts at your cars, there are plenty of places to spend money taht you probably need. Start by diagnosing the problem.

A few things you could tell us that would help are;

put a thermometer in the radiator and see if it agrees with your gauge.

does it run hot on the hyway or around town?

is the engine modified or stock?

what radiator do you have?

does it blow water out the overflow when it's reading hot?
 
1

19Nathen66

New Member
Mar 22, 2006
26
0
0
Apr 2, 2006
#14
  • Apr 2, 2006
  • #14
Its a factory radiator. Not modified, it does overflow a bit. It runs hot around town. Also it is a factory guage. Sounds like the shroud is the better way to go.
~thanks
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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south louisiana
Apr 3, 2006
#15
  • Apr 3, 2006
  • #15
19Nathen66 said:
Its a factory radiator. Not modified, it does overflow a bit. It runs hot around town. Also it is a factory guage. Sounds like the shroud is the better way to go.
~thanks
Click to expand...
I see you didn't learn anything from this
 

Cobain03

Active Member
Aug 27, 2003
996
0
36
Lexington, Ky
Apr 3, 2006
#16
  • Apr 3, 2006
  • #16
the previous owner switched my radiator out and now i dont have a shroud, and cannot get one since its not a stock radiator. i think im ognna have to....make one.
 

LMan

Founding Member
Aug 10, 2002
1,246
0
0
Mom's basement
Apr 3, 2006
#17
  • Apr 3, 2006
  • #17
D.Hearne said:
I see you didn't learn anything from this
Click to expand...


you can lead the newb to water, but......
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Apr 3, 2006
#18
  • Apr 3, 2006
  • #18
I have a stock '65-'66 rad in a mild cammed 302. It is a three row and I had it rebuilt last summer because the seam on the top tank let go. I can sit in rush hour traffic all day and it doesn't overheat. The stock guage stopped working a long time after the second sending unit went and I haven't found the need to replace it. I also don't have a shroud, although I would prefer one.

I originally had considered upgrading to a BeCool or equivelant rad instead of a rebuild, but am very glad I didn't throw money at it as it would have proven uneccessary. Just remember, there is a major difference in quality and efficiency between a Chinese stock rad and a Ford rad.
 
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