OK after the earlier disaster of a failed coolant flush/fill by a local shop that resulted in overheating, and my attempts to fill and bleed the system (resulting in my previous posts), the hits just keep on coming. While testing the car, after 55 minutes of driving on roads close to home, the coolant expansion tank exploded, literally busting around the middle seam.

WHAT WOULD CAUSE THIS? WHAT IS THE FIX?

HELP, PLEASE!

Len

 

Sounds like you overfilled the system with coolant. As the coolant heats, it expands and that's what your expansion tank is for. You'll need a new tank...they're not too expensive. Do you know where to note your fluid level within the tank when you are filling the system?

 

The expansion tanks, particularly the '02-'04, are prone to failure by bursting at the seam as you have experienced. This may be related to the recent overheating issues you've had.

The newer OEM expansion tanks are supposed to be more reliable, but you may also want to consider an aftermarket expansion tank by Forge or another vendor. I like this one and will be getting it when I do a coolant change:
http://www.livermoreperformance.com/mini_tanks.html

 

Yup it's pretty normal to see the expansion tanks leaking and sometime "explode" like you had.

Start by replacing the tank and bleeding the cooling system.

 

Yeah, I had my '04 tank come loose at the seam and spew some coolant. If this is the case of the OP, then the newer OEM tanks should be fine, and won't need replacing ASAP...in my experience. My tank spewed after some HARD driving at sustained RPMs of 5000+. If it exploded, then...there may be coolant overfill issues.

That Canton tank looks nice I've always had a thing for the Forge tanks though http://minspeed.net/FRT.htm ...more $$$, but nice.

 

Hmmm overheating followed by a burst coolant tank? Why isn't anyone else here remotely concerned about the condition of the head gasket?

 

Isn't that tank vented? I haven't seen one on a vehicle that wouldn't vent if overfilled.

 

go to forge in the vendor directory and get an aluminum tank . it takes the oem cap too .

 

or you can get an oem from mini car parts for 25.00

 

Good point, but the OP had stated in another thread related to this issue that the head gasket is good and there is no coolant in the oil.
https://www.northamericanmotoring.co...d.php?t=128463

 

minspeed.net carries the forge tank - very nice.

 

yeah they're pretty and nicer than my canton . not a bad deal considering it's a one time purchase . looks like a little keg . hmmmmm bear .

 

Drinking antifreeze out of the Forged keg may cause blindness.

I like the Canton better. Herbie, if you ever plan to replace with the Forged tank, I'll take your Canton.

 

if i'm swapping out the stock tank for a forge (no issues with the system itself) is a coolant flush necessary? or can I just swap tanks?

 

just suck the fluid out with a tranny baster and swap away .

 

if i do it i'll post and then the canton will be yours . but every dime is being saved for the rebore or stroker ,. it depends on jans price .