A/C low pressure switch connection 87 Fifth Avenue

Justwondering

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I'm totally hosed at this point.

There is a circular switch with two blades on it that screws into the side of the Expansion Valve -- The silver rectangle box on the firewall, passenger side engine compartment.

The pack rat chewed the wires off at the base of the switch.
I don't know where my replacement & its solid white wires should be spliced into.

The wiring diagrams on page 8-183 of the manual is of no help-- doesn't reference it.
The diagram on page 24-13 shows a great picture of the H valve, cycling clutch swith and the low pressure cut-off switch -- but no indication of what plugs into it.

So far I have recovered from all the rat eating damage except this low pressure switch and do I need to add grease (what type) to the suction tube before I insert that capillary tube?

I have completed:
1. spliced the choke wire
2. spliced the ignition coil wire
3. spliced the two wires for the new voltage regulator switch
4. spliced the two wires for the new cycling clutch switch.

JW
 

Justwondering

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Called my mechanic and asked if he had time to provide electrical counseling.
He laughed and said come on down.

Pulled in his place and showed him my pieces of wiring.
Showed him my fixes (butt splices).
Described my dilemma (4 wires need to go somewhere and I only find 2 available).

His quote (for weather here in Texas) 'You don't need to put the thermostat back in (little black box with the capillary tube). With this R134a it will never get as cool as the R12 so the likelihood of the thermostat kicking in is not high.'

He suggested I use the two wires that had been on the little black box thermostat for the low pressure switch.

So -- the little black box that was on the side of the H Valve (Expansion valve) have been removed. The round plug has been put on the two bladed, round low pressure switch which is also on the side of the H Valve (Expansion valve). This round plug is now using the two wires (blue/red and blue/white) that used to service the black box.

He did check and found that it was low on r134a.

After reconnecting everything I drove it 8 miles home. Put the rest of the parts back on. Tried tweaking the hood to get it lower on the front passenger corner (sigh -- no luck there).

Added a pound of refrigerant.
Handed the keys to my husband and asked him to take me driving.

He gets such a sh*t-eating grin on his face and happily gets in the car and away we go.

I will never grow weary of that feeling driving down the road - passenger or driver- it just feels so dang good!

JW
 

Justwondering

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I forgot to add -- I noticed the brakes were way down at the floor before braking started.
My thought was 'BudW would tell me there is a vacuum leak or a brake booster problem.'
(because he's told me that before ...lol).

When I got to the mechanic and popped the hood he looked at me and said 'You do realize your brake booster is got a vacuum leak?'.

Apparently the packrats had chewed one of the plugs off. It was just breathing in air big time.

Fixed that and the brakes improved as well as it quit running as rough!

JW
 
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