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Heating and Air Conditioning: Tools and Equipment

A/C adaptor valve VAG 1637, installing

Beginning with Vanagon production in May, 1988, the threaded connection on the A/C high pressure service valve has been changed from 7/16"-20 UNF to 3/8" - 24 UNF. Use special adaptor valve, VAG 1637, when making connections to the high pressure service valve.






Adaptor valve VAG 1637
1 - Schrader valve
2 - Adaptor
3 - Valve opener
4 - Sealing gasket






Installation position
1 - A/C high pressure line
2 - A/C high pressure service valve (3/8" - 24 UNF)
3 - Adaptor valve VAG 1637
4 - Service hose (to pressure gauge set)

- install adaptor valve VAG 1637 onto A/C high pressure service valve
- install A/C service hose onto adaptor valve VAG 1637