AC compressor takes very long to start

[snoozzie]

Hi guys !!

I have this little problem here.
every morning when I go out to work, I turn on the A/C system and it takes from 5 to 10 minutes for the compressor to kick in.
Once started it cools very nice, and belive me, when I tell you that AC is needed even at 7:00 am. the weather is very hot down here.

If I turn off the engine, and then turn it on again within an hour the compressor will kick in much faster.

At the end of the day, when I leave home from work, same story. I drive for almost 10 minutes and then finally the compressor kicks in.

I was told that the low pressure switch was going bad, so I disconnected the connector that goes there and jumped the connector with a short wire and the compressor didn't came in. So I connected it back and just waited a few minutes to start working.

Is there another switch that I might be missing ?
The switch that I disconnected is the one that it's on one side of that part that looks like an aluminum can that is very close to the evaporator.

Please advice on what to do.
Any help will be appreciated.

1995 Blazer LT 4x4
4.3 Vortec Vin W

[MT-2500]

Originally Posted by snoozzie

Hi guys !!

I have this little problem here.
every morning when I go out to work, I turn on the A/C system and it takes from 5 to 10 minutes for the compressor to kick in.
Once started it cools very nice, and belive me, when I tell you that AC is needed even at 7:00 am. the weather is very hot down here.

If I turn off the engine, and then turn it on again within an hour the compressor will kick in much faster.

At the end of the day, when I leave home from work, same story. I drive for almost 10 minutes and then finally the compressor kicks in.

I was told that the low pressure switch was going bad, so I disconnected the connector that goes there and jumped the connector with a short wire and the compressor didn't came in. So I connected it back and just waited a few minutes to start working.

Is there another switch that I might be missing ?
The switch that I disconnected is the one that it's on one side of that part that looks like an aluminum can that is very close to the evaporator.

Please advice on what to do.
Any help will be appreciated.

Several things could cause it.
Auto or manual air controls.
Any flashing lights on air cond control panel?
Have you checked for low freon?
Have you checked the wiring on pressure switch.
2 or 3 wire pressure switch?

That one uses a delay relay type relay for AC compresser.
MT

[jhong1226]

if you had jumped the two wires on the pressure switched should that compressor kick in though?

[snoozzie]

Thanks for the very fast responses. !!

For MT:
-Manual Controls.
-No lights in AC control panel.
-Haven't checked for low freon yet cause when it works it gets cold even when outside temperature is at 100.
-Haven't checked wiring yet.
-Pressure switch is 2 wire.

Where is that delay relay you mention ?

For jhong:
I was told that jumping the 2 wire connector the compressor should kick in even when low on freon.

[MT-2500]

Originally Posted by snoozzie

Thanks for the very fast responses. !!

For MT:
-Manual Controls.
-No lights in AC control panel.
-Haven't checked for low freon yet cause when it works it gets cold even when outside temperature is at 100.
-Haven't checked wiring yet.
-Pressure switch is 2 wire.

Where is that delay relay you mention ?

For jhong:
I was told that jumping the 2 wire connector the compressor should kick in even when low on freon.

Look on firewall bracket for relay.
But first thing get a test light and see if your are getting 12 volts to low pressure cut off switch and then 12 volts threw it and on to relay.
Lot of problems with wiring and plug in there.

http://members.troublecodes.net/crunch/95blazerair.pdf
MT

[old_master]

I recently ran across a similar problem on a GM Harrison H6 compressor. When the switch was on, the clutch would not engage. By gently bumping the clutch, it would engage and work flawlessly until the next day. As it turned out, the clutch face was worn and the gap was too wide for the field to pull in the clutch. A new clutch, (gapped properly) fixed it.

[value]

Originally Posted by old_master

I recently ran across a similar problem on a GM Harrison H6 compressor. When the switch was on, the clutch would not engage. By gently bumping the clutch, it would engage and work flawlessly until the next day. As it turned out, the clutch face was worn and the gap was too wide for the field to pull in the clutch. A new clutch, (gapped properly) fixed it.

--------------------------------------------------------------------
Can the clutch be adjusted?

[old_master]

Some H6 compressors use a shim or shims behind the clutch to acheive the proper gap, those clutches are pressed on to the compressor shaft. Some clutches are threaded onto the compressor shaft. With both types, the gap is adjustable.