gmctd wrote:
You doubters need to take a closer look at your t-stat housing - it is two (count'em: 2) piece assembly, cast in aluminum upper and lower pieces
- the main lower casting has a raised lip which precisely locates the....
- top casting's outer slightly tapered diameter which precisely centers as it is being inserted onto....
- the t-stat which has a slit rubber seal-ring around it's circumference
- the raised lip of the lower casting is then swaged inward around the upper casting, which....
- swaged taper securely locates and retains the upper casting against....
- the rubber seal-ring around the t-stat
To modify:
- mark the three new retaining holes for drilling
- drill and tap the holes for suitable stud fasteners
- remove (hacksaw? file? universal tool from Harbor Freight? Dremel? etc?) the swaged lower lip to separate the two casting halves
- may be possible to leave part of the lower lip to accurately locate the upper casting during t-stat replacement
- GM and others use that same t-stat in their cooling schemes
- can be had in several temperature ranges
And, btw and fyi: it would serve this modification well to drill and tap that boss inside the upper casting for an air bleed valve, such as the GM t-stat housings are factory-equipped
I agree. Mine was actually loose when I replaced it this fall. I could turn the top 1/2 inch in either direction.. Which told me it probably wasn't welded. Besides, Ultrasonic welding is for very thin material. (up to .020 or .030 inch) even these bodies would be far too thick.
I just threw mine in the 'to-do' box, thinking the exact same thing that OP has done.. kudos!
I'd take a hack saw, and score the outside diameter almost as deep as the wall appears.. maybe midway down. A small chisel should pop the 'ring' right off, if not at least in pieces. Aluminum will break away pretty easily.
Shoot, you'd probably only need to do the 'easy to reach' part of the housing, just to remove the 'lip'. After the top is off, going back in with a file or dremel tool will make short work of the remaining lip.. Just stay away from the 'flat' sealing surface.