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my car smells like coolant whenever I let it rip.

  • Thread starter Thread starter DarkoStoj
  • Start date Start date Jan 27, 2006

DarkoStoj

Founding Member
Sep 4, 2002
929
13
39
Detroit
Jan 27, 2006
#1
  • Jan 27, 2006
  • #1
I don't really beat on the car much (the 66 in sig) but whenever I really let it rip and get high in rpm's I can smell a little coolant on the inside of the car. I've been suspecting a leaking head gasket because I get white smoke on initial startup of the car when its cold, and it dies down to only a little at running temp, but its still there. Also I can see some bubbles in the coolant if I take the rad cap of and the coolant level is ~3" or so below full. I bought the car with a disconnected heat box because I had a leaky heater core, I put in a new heater core and hooked the heat back up, and thats when I first started smelling the coolant when i ragg on the car.
 

302 coupe

Founding Member
Mar 2, 2000
1,952
3
36
Macon, Ga.
Jan 27, 2006
#2
  • Jan 27, 2006
  • #2
do a leakdown test. If its a head gasket the cylinder will leak down pretty quick, plus you'll notice pressure and bubbles in the cooling system. Check the carpet/heater box for a leaky core.

not to be a wiseass, but don't you know how to diagnose a leaky head gasket? In another thread you're talking about building a blown, nitrous equipped 408 stroker. The skill range between these projects varies wildly.
 

DarkoStoj

Founding Member
Sep 4, 2002
929
13
39
Detroit
Jan 27, 2006
#3
  • Jan 27, 2006
  • #3
I already changed the heater core.

What kind of numbers should I be expecting for the leakdown test(never thought of it, and I got the thing sitting in my garage) I'm thinking either the head gaskets are toast or the rings aren't sealing like they should(which is allowing the car to smoke).
 

302 coupe

Founding Member
Mar 2, 2000
1,952
3
36
Macon, Ga.
Jan 27, 2006
#4
  • Jan 27, 2006
  • #4
for a leakdown test, I garb the fittings from my compression gauge/tester and hook it to the air hose coming from my air compressor. Put about 100 psi or so to the cylinder, if the head gasket is busted water will start flowing out of the radiator cap in about 10-15 seconds. You'll probably hear some bubbling/gargling sounds before that though. All but the smallest head gasket leaks canbe found like this. To do a leakdown test, I use the hose from the compression tester (with schrader valve), but remove the guage. Fill the cylinder with 100 psi or so, use a tire pressure gauge to get a psi reading. Check again in 10 seconds, 20 seconds, etc. You'll get a leakdown curve for whatever cylinders you test. This might take a certain variety of fittings and a certain type of comp tester that you may not have. Some of the testers are made all together, and some are assembled in different pieces so you can re-configure or use it for other stuff.
 

HistoricMustang

Active Member
Apr 11, 2003
2,359
0
46
Confederate States of America
Jan 27, 2006
#5
  • Jan 27, 2006
  • #5
DarkoStoj said:
I already changed the heater core.

What kind of numbers should I be expecting for the leakdown test(never thought of it, and I got the thing sitting in my garage) I'm thinking either the head gaskets are toast or the rings aren't sealing like they should(which is allowing the car to smoke).
Click to expand...

I am betting it is a heater core issue..............................when the system pressures up suddenly the core is a weak link. I actually split two cores in mine..........................this has been years ago.

HistoricMustang
www.historicmustang.com
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jan 27, 2006
#6
  • Jan 27, 2006
  • #6
yeah, reach in the heater box or sniff around it,probably a pin hole or loose clamp
 

2nd Mustang

Founding Member
Feb 24, 2002
2,488
0
46
Southern California
Jan 27, 2006
#7
  • Jan 27, 2006
  • #7
iskwezm said:
yeah, reah in the heater box or sniff around it,probably a pin hole or loose clamp
Click to expand...

I vote for a loose clamp. Sometimes they are a bear to tighten up under the dash. If it's a leaky core, well, Murphy's Law.
 
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