Has anyone repaired a cracked coolant reservoir?

[elgyqc]

I just replaced the coolant reservoir and since the engine was out I did not have to destroy the old one to get it out. Since I hate to throw away things I got to wondering if it would be possible to fix this.



Plastics are a mystery to me, is there a spray on coating that would seal the existing and future cracks (I have my doubts). Or is there a sealant that could be poured into the tank that would seal and strengthen the bottom? It would have to adhere to the tank and be flexible enough to not crack itself.

[JFP in PA]

Many have tried, I know of none that succeeded...................

[78F350]

The best automotive analogy I can think of is an aged out tire. Even if it has tread left, the material is degraded throughout. You can put a tube inside and get some more miles from it, but at any time it could fail catastrophically.
The material of the coolant tank has been pressurized and heated for many thousands of cycles. The bonds that bind the plastic on a microscopic level are failing. I don't think there is any practical way to extend it's use. Any patching of a crack would be short lived as the crack extends or a new one develops outside the patch.

[elgyqc]

Originally Posted by 78F350

The best automotive analogy I can think of is an aged out tire. Even if it has tread left, the material is degraded throughout. You can put a tube inside and get some more miles from it, but at any time it could fail catastrophically.
The material of the coolant tank has been pressurized and heated for many thousands of cycles. The bonds that bind the plastic on a microscopic level are failing. I don't think there is any practical way to extend it's use. Any patching of a crack would be short lived as the crack extends or a new one develops outside the patch.

Well you let the air out of my tires
Sounds logical to me.

[Gilles]

Originally Posted by JFP in PA

Many have tried, I know of none that succeeded...................

I did it and it worked.. (but not recommended)

Many years ago, bought a Fiat X1/9 (I was living in Mexico..) and the coolant tank burst a seam, in those years without internet I had to wait a long time to get a new tank shipped to the Texas border and then shipped to me in central Mexico (+/- a couple of months..)

Therefore, my McGiver solution was to mix a kind of 'runny epoxy mix' and pour it inside the tank, one side first and then again for the other half of the reservoir and it worked just fine for a couple years until I installed the new tank.

[MasterDesigner]

there is a jb weld product specifically design for plastics, you sand the area to make it rough and it works very well but as others mentioned I would not trust it as a long time solution