Charge the tyre with air conditioning fluid then use a sniffer or an ultraviolet light. See

http://www.justoffbase.co.uk/Air-Conditioning-Leak-Detection-Kit-Sealey-VS600

also see Adixen.co.uk maybe for some ideas.

Normal engineering crack detection techniques, so called

- dye penetrant

or

- ultrasonic scanning

around the rim.


I know it is very hard to fine small leaks. There was man on Ebay selling a wheel that was replaced by the MB dealer. He/they eventually found the crack in the rim; welded it and was selling the wheel.

Loose valve might be worth checking, but i'm betting on it being a slight bead seal leak. JimFreeh's method is the best check, adding a little dish soap to the water will make it even more visible (and fun for kids!!). While you have the soapy water out, brush a little onto the valve stem and valve.

Good luck.

__________________
Earl McLain
'02 C230 Kompressor
'89 560 SEL "Frau BlueCar" (retired April 2004)

If you can get the tire off, use steel wool to clean off the rim where the tire bead seats. You should also clean the tire bead with the steel wool. Then, reinflate and reseat with soapy water on the bead.

x2 on the valve stem and/or seal

__________________
2009 E320 Bluetec 117,000
1995 E300D 306,000 Sold
1996 Ford Taurus LX 130,000 Sold
1985 300TD Still 225,000 Sold
2016 Ford Fusion 24,900

Errrr....This seems:

- cost prohibitive
- potentially illegal depending on refrigerant
- not very logical

How about using soapy water? Any tiny leak will bubble up if the water has soap in it.

__________________
TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth