Good for you and Good to know! Thanks.
Leak - FINALLY Solved it!!
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,598
Likes: 31
Cruise-In X Veteran
St. Jude Donor '09
Leak - FINALLY Solved it!!
A week or so ago I posted about a leak of Dex Cool on my garage floor right behind the driver's side front wheel, It wasn't much but it was enough to cause concern. I took the car to my regular mechanic who couldn't find anything wrong, I had to take the car to the Dealership for something else and while it was there they put the system under pressure and could not find a leak? I drove home from the Dealership and after parking the car went down to the garage several hours later and there it was, a trail of Dex Cool. I posted about it here on the Forum hoping someone would have the answer as to what it could be, I got some good suggestions but none solved the problem. I guess I really am the first one to have this happen as no one knew what it the cause was.......It was the coolant recovery tank cap!!!! It seems that the cap has a pressure sensor that closes when the system heats/expands but my cap was not functioning properly thus when I got on it the inertia of the liquid would hit the back of the tank and spill a little Dex Cool out of the overflow. It took an 8 dollar cap from Rock Auto to fix! I hope if anyone has this problem you'll know what's wrong....the Dealer and two mechanics didn't!!!!!!!!!
Drifting
Joined: Jul 2009
Posts: 1,435
Likes: 19
From: Sioux Falls South Dakota
A week or so ago I posted about a leak of Dex Cool on my garage floor right behind the driver's side front wheel, It wasn't much but it was enough to cause concern. I took the car to my regular mechanic who couldn't find anything wrong, I had to take the car to the Dealership for something else and while it was there they put the system under pressure and could not find a leak? I drove home from the Dealership and after parking the car went down to the garage several hours later and there it was, a trail of Dex Cool. I posted about it here on the Forum hoping someone would have the answer as to what it could be, I got some good suggestions but none solved the problem. I guess I really am the first one to have this happen as no one knew what it the cause was.......It was the coolant recovery tank cap!!!! It seems that the cap has a pressure sensor that closes when the system heats/expands but my cap was not functioning properly thus when I got on it the inertia of the liquid would hit the back of the tank and spill a little Dex Cool out of the overflow. It took an 8 dollar cap from Rock Auto to fix! I hope if anyone has this problem you'll know what's wrong....the Dealer and two mechanics didn't!!!!!!!!!
The issues was with how the caps allows the pressure to release.
This is similar to the old muscle cars with the pressure release tab on the radiator cap that you need to pull up to relieve the pressure when the car is hot. I've had those where when at normal temp the cap is fine but as soon as it starts to cool the gasket on the cap loses it's seal and you can watch it drip antifreeze from the cap.
Last edited by IDSRVIT; Apr 21, 2017 at 07:40 AM.
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,598
Likes: 31
Cruise-In X Veteran
St. Jude Donor '09
In defense of the dealer and mechanics, when they do their pressure test it simulates the system at pressure so the cap would most likely seal properly. I can see how they would not catch this.
The issues was with how the caps allows the pressure to release.
This is similar to the old muscle cars with the pressure release tab on the radiator cap that you need to pull up to relieve the pressure when the car is hot. I've had those where when at normal temp the cap is fine but as soon as it starts to cool the gasket on the cap loses it's seal and you can watch it drip antifreeze from the cap.
The issues was with how the caps allows the pressure to release.
This is similar to the old muscle cars with the pressure release tab on the radiator cap that you need to pull up to relieve the pressure when the car is hot. I've had those where when at normal temp the cap is fine but as soon as it starts to cool the gasket on the cap loses it's seal and you can watch it drip antifreeze from the cap.
Race Director
Joined: Sep 2009
Posts: 11,351
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From: Eastern
Believe me that I was relieved when they couldn't find anything wrong and correct me if I'm not right but don't they connect to the system to do a pressure test through the filler where the bad cap was? I believe that's why they couldn't id the cap as being the culprit......
Great find for sure. High end pressure testers have provisions for testing the cap for proper operation. Apparently, they did not do that.
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Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,598
Likes: 31
Cruise-In X Veteran
St. Jude Donor '09
Yes, that's exactly where they would hook up their pressure tester, which acts as a cap, but also seals the overflow tube to prevent any anti-freeze from escaping that way.
Great find for sure. High end pressure testers have provisions for testing the cap for proper operation. Apparently, they did not do that.
Great find for sure. High end pressure testers have provisions for testing the cap for proper operation. Apparently, they did not do that.
Thread Starter
Drifting
Joined: Apr 2006
Posts: 1,598
Likes: 31
Cruise-In X Veteran
St. Jude Donor '09