Better AC with different size pulley?

[JohnZ71]

That is the larger pulley. The belt rides in a recess behind the clutch face of the pulley on the smaller pulley.

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This is encouraging. Do you know if it’s easy to swap pulleys? Hopefully the system doesn’t need to be evacuated.

 

[JohnZ71]

I would also investigate whether there's undesired airflow:

- The seal b/t the front air handler and the cowl (pictured) is notorious for leaks; it leaks on my Suburban, which is very evident in the wintertime b/c it allows a cold draft of air to enter behind the glovebox into the cabin. Certainly in the summer there's a warm, humid draft.

- The seals b/t the dampers within the air handler may not be routing the air completely though the evaporator / around the heater core

Others will hopefully comment.

@east302 has posted often about air handler issues / rebuilds, as have others.

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(this picture is courtesy of someone else; I pirated it years ago, possibly from someone on GMT400)

I’ve never checked, but I will. I don’t recall any cold draft in the winter, but who knows. Thanks!

 

[JohnZ71]

This is the compressor on one of my parts z71 tahoes. Assuming it’s the original compressor and appears to have the smaller pulley. Is that correct?

 

[1998_K1500_Sub]

I’ve never checked, but I will. I don’t recall any cold draft in the winter, but who knows. Thanks!

You might consider installing a coolant shutoff or bypass valve to stop the flow through the heater core.

A simple solution would suffice... a ball valve, whatever.

My Suburban and a number of other GMT400s came with a vacuum operated bypass valve as OE. This valve's still available on RockAuto, but it's vacuum operated.

Toyota has an electrically-controlled vacuum switching valve (attached) that could be repurposed to control vacuum to the the OE bypass valve.

 

[L31MaxExpress]

This is encouraging. Do you know if it’s easy to swap pulleys? Hopefully the system doesn’t need to be evacuated.

On a stock compressor, the clutches interchange. I have no idea if they do on the aftermarket ones. The stock ones need a puller and installer and a pair of snap ring pliers to remove. I have not changed the clutch only in a decade or so although I would have in my 2007 G35 a few years ago had a replacement clutch been available. The clutch coil failed and it cooled perfectly before it did.

 

[MalcolmEatmanGoode]

Do we have part numbers do this compressor and condenser that’s mentioned?

 

[1998_K1500_Sub]

This is the compressor on one of my parts z71 tahoes. Assuming it’s the original compressor and appears to have the smaller pulley. Is that correct?

Checking RockAuto for the specs on a UAC CO20151C HT6 compressor, it shows the pulley is a 5" / 125mm diameter:

Pulley Diameter (MM)

125

Take a look at other compressors on RockAuto's site for various GMT400s / vans and determine for yourself what size pulley might be found where.

I've seen the Sanden replacement compressors offered with 5.12" / 130mm and 4.4" / 112mm pulleys, there might be similar sizes offered on HT6 compressors; this jibes with what @L31MaxExpress mentioned in his prior post.

 

[Vettepilot]

My problem is air flow. I rebuilt the entire system. Replaced virtually everything, including verifying all actuators, I made a heater coolant cutoff, new, high quality HVAC fan, etc.

But it just does not blow hard enough. (Yes, my new blower switches to high, and I cleaned the evaporator. Air doors are switching.) I am actually looking at buying auxilliary fans to augment somehow.

Is there any way to get more airflow out of the factory system??

Vettepilot

 

[JohnZ71]

My problem is air flow. I rebuilt the entire system. Replaced virtually everything, including verifying all actuators, I made a heater coolant cutoff, new, high quality HVAC fan, etc.

But it just does not blow hard enough. (Yes, my new blower switches to high, and I cleaned the evaporator. Air doors are switching.) I am actually looking at buying auxilliary fans to augment somehow.

Is there any way to get more airflow out of the factory system??

Vettepilot

Idk but I hope something can be figured out. I have the same issue. My jeep blows a ton of air, it’s luxury.

 

[Vettepilot]

I don't know, but it's really bothering me, as I like the truck. But this stuff isn't just casual comfort here, it's life or death. It runs 125 to 130 here. Lake Havasu City, Az. The weather service says only about 118, but our multiple thermometers say different. Pic is from today...

I have seen that thermometer in the shade near the pool, beyond pointing straight down, many times. Our "real", mercury thermometers say the same...

Anyway, help with the blower???

Vettepilot