<center><img src="http://pictureposter.audiworld.com/69811/coolant_tank.jpg"></center><p>Is this cracking common? I think the tank is an aftermarket item - pretty clean and says "made in Italy"
Do the tank caps not work after an overflow because they no longer hold pressure or is it because they won't release the pressure?
What's the cheapest source for a coolant tank besides a wrecking yard?

I believe that's a fairly common problem. Mine had a pin hole size leak on the very top. I bought a new one from Blaufergnugen. They also come with a new low coolant sensor. I see you have a 164L, my daily driver used to be a 91 164S before I bought the 5000. How do you like it?
Randolph
87 5KCSTQ
93 928GTS

and maybe 100's too.

It's a German Meyle brand tank and not the crappy Italian one.
I tried epoxy in the crack but the tank expands to much and the epoxy won't hold.

According to all the folks after experiencing a boil over.
I alway carry an extra one in the trunk. Just unscrew 'em from VW/Audis at a junk yard.

The 164L is a real treat to drive. The auto transmissions are really smooth and responsive.
I wish those crazy Italians gave me a couple more inches in the engine bay. And parts are expensive. Not as much as my old Peugeot though :-)

They are really nice cars. I miss the interior on mine, it had the Recaro seats. Mine was a 5spd but I've driven the auto's and they are responsive. The auto trans on the 164's have the same reputation as the auto's on the 5000's. So keep that fluid changed!! BTW there is a great Alfa forum if you need the link LMK.
Randolph
87 5KCSTQ
93 928GTS

after a while the plastic gives out and cracks just like in your photo. My old VW does the same thing. I snare a spare at the wrecking yard, when I see a nice one. The crack cannot be glued or sealed.

Only time to be concerned, is if you find the expansion tank bulging from excessinve internal pressure. If and when you see that, you should suspect a bad head gasket that is allowing hot exhaust gas to enter the cooling system.............Rooster

They like to crack due to expansion or leak at the temp sensor.

Steve
Michigan