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  • 1965 - 1973 Classic Mustangs -General/Talk-

New Problem With 65

  • Thread starter Thread starter Scrasauge
  • Start date Start date May 29, 2014

Scrasauge

Active Member
Sep 24, 2003
118
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Reserve, La
May 29, 2014
#1
  • May 29, 2014
  • #1
I changed the water pump then I changed all the hoses and radiator then started the car up and the water was shooting out the radiator like crazy when it got warm! Does this mean I have a blown head gasket or should I be looking for something else? No water in the oil at all! Trying to solve this issue! Anyone can help me also changed the thermostat and hoses....
 

horse sence

15 Year Member
Nov 29, 1999
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Wile Coyote's stunt double
May 29, 2014
#2
  • May 29, 2014
  • #2
block had air pocket most likely ,is it the correct rotation water pump?
 

Scrasauge

Active Member
Sep 24, 2003
118
5
29
Reserve, La
May 30, 2014
#3
  • May 30, 2014
  • #3
I'm led to believe the water pump is the right rotation? But how do I figure out if it isn't ? It has a 302 out of a 74 maverick I believe and also the water pump water neck comes out on the bottom driver side! And also I had plugged off the by pass hose because I couldn't get it on with top radiator hose
 

Scrasauge

Active Member
Sep 24, 2003
118
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29
Reserve, La
May 30, 2014
#4
  • May 30, 2014
  • #4
Also once the thermostat opened the water shot out of the neck of the radiator a lot almost throwing all of the water out of it.
 

rbohm

Founding Member
Apr 12, 2002
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tucson,az
May 30, 2014
#5
  • May 30, 2014
  • #5
it sounds to me like there is a big air bubble in the block somewhere. usually what i do is drill a 1/8" hole in the thermostat towards the edge, then install it with the hole pointing up, and then fill the radiator. that way as i fill the system, the air can bleed out thus minimizing air pockets. i would also put the rad cap back on, but not fully tightened, until the engine warms up. that way you again minimize the possibility of coolant shooting out the rad while the engine fully warms up.
 

Scrasauge

Active Member
Sep 24, 2003
118
5
29
Reserve, La
May 30, 2014
#6
  • May 30, 2014
  • #6
The thermostat I have has the small weep hole in it already! But I noticed its a 195 degree! I think that's kinda high. What you think?
 
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horse sence

15 Year Member
Nov 29, 1999
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Wile Coyote's stunt double
May 30, 2014
#7
  • May 30, 2014
  • #7
Scrasauge said:
The thermostat I have has the small weep hole in it already! But I noticed its a 195 degree! I think that's kinda high. What you think?
Click to expand...
That is to hot ,change it to 180*
 

horse sence

15 Year Member
Nov 29, 1999
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May 30, 2014
#8
  • May 30, 2014
  • #8
I just did a motor in an expedition ,i know it is two different things completely , but i took the heater hose off at the intake and filled the block there ,that is behind the thermostat and it filled the block completely .check it at the radiator cap after you replace the heater hose to make sure the radiator is full. This should remove any or most any trapped air .
 

Scrasauge

Active Member
Sep 24, 2003
118
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Reserve, La
May 30, 2014
#9
  • May 30, 2014
  • #9
Ok, I put a 180 thermostat in and got the bypass hose back in and it seems to working good now! I have friend coming with an exhaust gas tester to put in the radiator just to verify that I don't have a blown head gasket! Before I go any further! But did let it run the driveway for about 45 minutes and used a temp gun pointed on the side of the temp sending unit and it got to almost 200 but never went above that unlike it did yesterday
 

horse sence

15 Year Member
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May 30, 2014
#10
  • May 30, 2014
  • #10
Yeah, you more than likely had trapped air .
 

Scrasauge

Active Member
Sep 24, 2003
118
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Reserve, La
May 31, 2014
#11
  • May 31, 2014
  • #11
Ok seems it was fine for a while earlier then we put the combustion gas tester on it and it seems it turned yellow indicating that it has a blown head gasket, but also while running it so long in the driveway it started to boil over on me! Looks like I'm pulling the engine today and re sealing it and changing them and putting a coat of paint on it
 

rbohm

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Apr 12, 2002
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Jun 7, 2014
#12
  • Jun 7, 2014
  • #12
Scrasauge said:
The thermostat I have has the small weep hole in it already! But I noticed its a 195 degree! I think that's kinda high. What you think?
Click to expand...

no 195 is not too hot, as long as the rest of the cooling system can handle it. my 66 had a 192 tstat in it when i got it.
 

no1hedberg

Member
Aug 5, 2013
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9
Jun 8, 2014
#13
  • Jun 8, 2014
  • #13
It's pretty hot for older engines that were designed to run on leaded fuel. Modern engines are designed to run much hotter for emissions reasons. They also have higher quality pistons, rings, and hardened valve seats to tolerate the much higher combustion temps associated with unleaded fuel, exhaust gas recirculation, and higher cooling system temps.
 
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