AC Charging Hose Hookup on a 73 Vette

[Dennis H.]

My 1973 AC system consists of an Evaporator, VIR, AC Compressor and Condenser. The Low-Pressure hookup is a fixed (R12) schrader valve on the VIR and the High-Pressure hookup is at the AC Compressor manifold and has a R-134 connection.

I have tried every possible hose and adapter I have to connect to the Low-Pressure schrader valve on the VIR but can't get the hose to clear the evaporator housing as there is only 3/4" of clearance.

Any ideas on what I need?

[Doug C.]

Re: AC Charging Hose Hookup on a 73 Vette

Check the manifold block on the compressor. If you have a "rounded" block the Schrader valve on the left port is low pressure. See the TIM&J manual (3rd edition page 153) for pictures. Do you have a steel line along the right fender with a site glass, high pressure cutout switch and high pressure Schrader valve?

[Dennis H.]

Re: AC Charging Hose Hookup on a 73 Vette

I have the 1973 rectangular manifold block that is shown in Fig. M 17.2 with the high-pressure fitting on the right hand side. There is no site glass on a 1973 Corvette.

I find this whole thing weird; the dealers serviced the AC system on these cars back in the day and I'm sure coming forward 73 owners have also serviced the AC system. On page 153 of the TIM&J manual 3rd edition you will see Fig. 17.5 that is the VIR, the distance from the schrader valve and the evaporator housing is 3/4" making it impossible to connect my HVAC hose.

[Dennis H.]

Re: AC Charging Hose Hookup on a 73 Vette

Found this in my internet travels.

Attaching the low pressure hose of the gauge set to the VIR assembly can be challenging. This 90-degree adapter was modified to facilitate connecting the hose in these cramped quarters.

[Dennis H.]

Re: AC Charging Hose Hookup on a 73 Vette

Found this at Grainger, ordered it today and will give it a try.

[Doug C.]

Re: AC Charging Hose Hookup on a 73 Vette

I thought your 73 might have the service hose set 346137 installed. See the attached service bulletin. My very early 74 came with the 73 style hose set. After two hose set failures 346137 was installed under warranty.

[Dennis H.]

Re: AC Charging Hose Hookup on a 73 Vette

Thanks Doug, interesting TB.