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Engine Overheating issues

  • Thread starter Thread starter Maciasmarci
  • Start date Start date Aug 20, 2021
M

Maciasmarci

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May 19, 2021
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Stockton
Aug 20, 2021
#1
  • Aug 20, 2021
  • #1
I have a 90’ fox body 306 with stock intake and 19lb injectors , cold air intake. Been chasing an ongoing issue with car overheating as soon as I start driving the car. Temp guage would be just before the middle line during idle and rises as I leave my driveway. I have a radiator from autozone, new thermostat, pump, did a blown gasket test.(good) and new hoses. I have a 10 blade 15” electric fan unknown company with 200 degree fan switch. It’s 98 degrees out where I live. Don’t know what else to do
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Aug 20, 2021
#2
  • Aug 20, 2021
  • #2
Need some info like:
What is the actual temp and how many degrees it rises when driving, in traffic, ac off. This requires installing an aftermarket gauge.
what cfm is the electric fan
What temperature is the thermostat
 
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Boostedpimp

20+ Year Stangneter
May 8, 2003
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NJ
Aug 20, 2021
#3
  • Aug 20, 2021
  • #3
I would make sure to bleed all the possible air out of the cooling system and then look at that efan real hard. Pull some numbers off it and do research to see what kind of cfm it is tossing.. if you can't find anything on it junk it and toss stock clutch setup back on or go with a known quality efan that puts decent cfm out.
 

nickyb

I gotta say i never painted my nuts, Never Ever
15 Year Member
Apr 3, 2009
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nevada
Aug 20, 2021
#4
  • Aug 20, 2021
  • #4
If you let it idle in your driveway will it overheat? Have you had the cap off rad and watched for circulation of coolant? Have you seen IF the efan comes on?
By overheating do you mean it boils over and comes out the overflow tank? There are so many things that it could be that you'll have to check a lot before replacing stuff.
 
M

Maciasmarci

Member
May 19, 2021
53
1
8
Stockton
Aug 20, 2021
#5
  • Aug 20, 2021
  • #5
General karthief said:
Need some info like:
What is the actual temp and how many degrees it rises when driving, in traffic, ac off. This requires installing an aftermarket gauge.
what cfm is the electric fan
What temperature is the thermostat
Click to expand...
 
M

Maciasmarci

Member
May 19, 2021
53
1
8
Stockton
Aug 20, 2021
#6
  • Aug 20, 2021
  • #6
Therm is 190, Fan is probably 2800 Cfm I looked at one similar to the one i have so it’s probably the same. But again it’s an old fan so idk. Yea Ill probably buy a cheap gauge for it
 
M

Maciasmarci

Member
May 19, 2021
53
1
8
Stockton
Aug 20, 2021
#7
  • Aug 20, 2021
  • #7
nickyb said:
If you let it idle in your driveway will it overheat? Have you had the cap off rad and watched for circulation of coolant? Have you seen IF the efan comes on?
By overheating do you mean it boils over and comes out the overflow tank? There are so many things that it could be that you'll have to check a lot before replacing stuff.
Click to expand...
It’ll stay a bit below or at midpoint on the gauge during idle. Yea it looks like it’s flowing. Yes the fan is working. So as soon as I drive off from my house it slowly tends to rise above midpoint even towards 3/4 of the gauge. But no leaks are present it’s just hot. I noticed while I’m purging air, it seems like water is boiling even though I’ve already tested the cooling system for combustion gases.
 

KRUISR

10 Year Member
Apr 16, 2015
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Aug 20, 2021
#8
  • Aug 20, 2021
  • #8
Maciasmarci said:
it seems like water is boiling
Click to expand...

Is it straight water or coolant/water mix?

Take a pic of the rad/fan so we can see coverage area on the fan.

Where is the temperature sensor for your fan controller located?

Stock gauge can vary from car to car. Also if gauge temperature sensor is changed it can change where the gauge shows normal. When I change mine, 200* jumped up one line on the gauge, from right in the middle before to one line up after.
 

mikestang63

SN Certified Technician
Aug 27, 2012
11,606
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In the garage
Aug 20, 2021
#9
  • Aug 20, 2021
  • #9
airflow problem-is your front deflector and shielding panels in place. what fans are you running
air in system- get a lisle funnel and burp out all the air
coolant flow- did you test the thermostat .
is it a new radiator cap
 
M

mercurycapri

Member
May 30, 2006
211
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18
washington
Aug 26, 2021
#10
  • Aug 26, 2021
  • #10
I would defiantly guess your water pump is standard rotation not reverse. My dad had the same issue
 
M

Middleagecrisis

Active Member
Aug 23, 2020
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Seguin
Aug 28, 2021
#11
  • Aug 28, 2021
  • #11
Just throwing this out as an option if everything else is good/correctly installed. I've seen some motors that had an incredibly amount of sediment in them from the owners never changing the coolant. I've got an explorer 5.0 bare block setting on the engine stand that I had to take to my local machine shop and have them bake it to get all the crap out that I couldn't get out after an hour's work with cleaning brushes and a water hose. The block was perfect otherwise and is going back together with standard uncut crank and a stock bore. This motor would have always had cooling problems from the junk in the water passages, no matter what fixes I threw at it! Hopefully, you don't have the same problem.
 
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