Cooling System Help
Thread Starter
Heel & Toe
Joined: Dec 2012
Posts: 20
Likes: 0
From: Apex NC
Cooling System Help
Car: 2003 Convertible. I have had a cooling system "smell" issue for several months. Its in the engine bay near the recovery tank and not inside at the heater core. After driving the car and parking it in the garage, I smell coolant and its strong when I lift the hood. (note: I did a coolant flush 6 months ago). I did a coolant recovery tank replacement and cap. The smell still is there after every drive but no coolant leak (level always stays the same)? No puddles or drips. I just bought a cooling system pressure tester to figure this out and did a test (~16 PSI) and it dropped 1 PSI over a half hour but no indications of leak, no sound of leaking or nor smell. I am lost on what to do. I am afraid to raise the pressure on the tester to cause any issues. Any ideas on what to do next?
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Try popping your air filter off and removing you upper radiator support. Put a real close eyeball on your radiator end tanks, both sides, while pumping your pressure up.
Btw, don't be afraid to run your pressure up to 18 psi. GM revised the cap pressure from 15 to 18 on the C5s even when they were still in production, so the system can easily handle it.
Btw, don't be afraid to run your pressure up to 18 psi. GM revised the cap pressure from 15 to 18 on the C5s even when they were still in production, so the system can easily handle it.
Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
MB, love your latest avatar pic. Is that "Fukushima Dog?" 
Btw, were you going for Traumaville on your location?
Btw, were you going for Traumaville on your location?
Le Mans Master
Joined: Sep 2003
Posts: 8,847
Likes: 795
From: Longview Texas
Is your pressure tester testing the system with or without the pressure cap on?
I would think if it leaks down within 30 minutes, there has to be a leak somewhere.
As suggested, check for cracks in the end tanks, or small leaks around the radiator core tubes.
Have you checked for the obvious leak at the water pump seal? I have had pumps leak enough to produce a smell before they ever leaked enough to drip... They can also leak when you start the engine cold, and stop leaking as it heats up, or vise versa.
I would think if it leaks down within 30 minutes, there has to be a leak somewhere.
As suggested, check for cracks in the end tanks, or small leaks around the radiator core tubes.
Have you checked for the obvious leak at the water pump seal? I have had pumps leak enough to produce a smell before they ever leaked enough to drip... They can also leak when you start the engine cold, and stop leaking as it heats up, or vise versa.
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From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
http://www.toxicavenger.com/
Team Owner
Joined: May 2001
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
LOL, My location is correct if you are familiar with The Toxic Avenger.
http://www.toxicavenger.com/
http://www.toxicavenger.com/
Drifting
Joined: Sep 2009
Posts: 1,305
Likes: 80
From: Hollister CA
Car: 2003 Convertible. I have had a cooling system "smell" issue for several months. Its in the engine bay near the recovery tank and not inside at the heater core. After driving the car and parking it in the garage, I smell coolant and its strong when I lift the hood. (note: I did a coolant flush 6 months ago). I did a coolant recovery tank replacement and cap. The smell still is there after every drive but no coolant leak (level always stays the same)? No puddles or drips. I just bought a cooling system pressure tester to figure this out and did a test (~16 PSI) and it dropped 1 PSI over a half hour but no indications of leak, no sound of leaking or nor smell. I am lost on what to do. I am afraid to raise the pressure on the tester to cause any issues. Any ideas on what to do next?
Last edited by bobeast; Oct 25, 2013 at 07:22 PM.
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Thread Starter
Heel & Toe
Joined: Dec 2012
Posts: 20
Likes: 0
From: Apex NC
BobEast and others. Thanks for the replies. All testing has been with a cold system. I will pressure test again (cold) up to the suggested 18PSI and make sure that the tester (pump hose clamps and expansion tank connector) is on tight to take that out of the equation. It smells when warmed up so the steam theory makes sense. Car is 10 years old so gaskets may be needed. I just wanted to see if I could find it before replacing things.
Le Mans Master
Joined: May 2005
Posts: 6,366
Likes: 249
From: Fort Lauderdale, Florida
I know you said you replaced the cap on the recovery tank, but I would check it again if you can test it separately. I had a similar problem on my 10 year old car. No leaks anywhere but had the smell in the same area. I bought a new cap from Amazon, of all places. Cured the problem. I think it might have been Chip at CCA who told me he had the same problem and it's not really a problem if you're not having a coolant loss. However I didn't like the sudden change in aroma. The new cap fixed it. Maybe you just need another new cap.