Expansion tank cap failing?
#1
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Does this look like a failing expansion tank cap?
My part # is 996-106-447-01 and Pelican shows 996-106-447-04-M100 - which I assume is a revised and newer part - based on the 04 at the end.
I have cleaned it up to see if there is a leak, but for the $30, maybe it just makes sense to replace.
Query - Would this kind of failure cause operating temperatures to be higher than normal?
![](http://i480.photobucket.com/albums/rr167/fbgh2o/IMG_0277.jpg)
My part # is 996-106-447-01 and Pelican shows 996-106-447-04-M100 - which I assume is a revised and newer part - based on the 04 at the end.
I have cleaned it up to see if there is a leak, but for the $30, maybe it just makes sense to replace.
Query - Would this kind of failure cause operating temperatures to be higher than normal?
![](http://i480.photobucket.com/albums/rr167/fbgh2o/IMG_0277.jpg)
![](http://i480.photobucket.com/albums/rr167/fbgh2o/IMG_0278.jpg)
#5
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#7
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Ordered a new one this morning. Pick up this afternoon.
I cleaned up everything last night and replaced the cap - what I thought was good and tight. I guess not, I dumped a bunch of coolant this morning as I pulled in the parking lot at work. I hope it was the cap and not that my actions last night caused the tank to crack somehow.
I cleaned up everything last night and replaced the cap - what I thought was good and tight. I guess not, I dumped a bunch of coolant this morning as I pulled in the parking lot at work. I hope it was the cap and not that my actions last night caused the tank to crack somehow.
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#8
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Are you saying you put the new cap on and the system dumped a lot of radiator fluid?
If a cooling system doesn't keep the required pressure the fluid is more prone to boil. Once boiling starts and pressure is release through a leak then its like a pot boiling and it goes into an over boil hence more coolant loss.
If a cooling system doesn't keep the required pressure the fluid is more prone to boil. Once boiling starts and pressure is release through a leak then its like a pot boiling and it goes into an over boil hence more coolant loss.
#9
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I couldnt see the cracks in my tank till I removed it...hairline fractures in rear of tank...that would only spring a leak under pressure. If I were you Id replace the coolant reservior....mine was about that yellowed when it developed small cracks.
#10
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Next time washing and waxing make sure you wash the rim of your engine comparment like where the picture shows and other points developing a coating of grime. I like using a spray on carnuba by eagle 1 that you can spray on when the car is still wet then shami off the water and the area is waxed.
#12
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Are you saying you put the new cap on and the system dumped a lot of radiator fluid?
I managed to get the car home without it leaking again, but after I stopped and parked it, I could hear the pressure venting from near the tank opening. If you look closely the seal is pretty old and had a relatively deep impression in it - so I am going to guess it was probably the issue.
If I were you Id replace the coolant reservoir....mine was about that yellowed when it developed small cracks.
#13
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If that's the original tank, I'm suprised it lasted 10 years. It could have been that your re-tightening the cap made a better seal and the pressure caused a previously unseen crack(s) to fail.