A/C Manifold Gauge Readings

[uscmas412]

Ok a few updates:

Misting didn’t seem to help, drove home 20 minutes, parked and idled. Misted condenser and waited a few minutes. No significant change.

Tried 2x more times today and no significant change from the dry condenser dash temps.

Added ~12oz of r143 and here’s the gauge reading. Still seems whacky but there was a small drop in temp.

Dash temps at idle with hood open, 90 degrees ambient. This temp is manageable for sure with windows closed.

FWIW my coolant temps on the ECU data never exceed 194. I never notice engine fan noise (as in a roar) and my front windshield is aftermarket with no tint. During a normal drive on a sunny afternoon the heat from the windshield overpowers the AC IMO.

 

[flintknapper]

Thanks f

Ok a few updates:

Misting didn’t seem to help, drove home 20 minutes, parked and idled. Misted condenser and waited a few minutes. No significant change.

Tried 2x more times today and no significant change from the dry condenser dash temps.

Added ~12oz of r143 and here’s the gauge reading. Still seems whacky but there was a small drop in temp.

View attachment 3658659

Dash temps at idle with hood open, 90 degrees ambient. This temp is manageable for sure with windows closed.
View attachment 3658660

FWIW my coolant temps on the ECU data never exceed 194. I never notice engine fan noise (as in a roar) and my front windshield is aftermarket with no tint. During a normal drive on a sunny afternoon the heat from the windshield overpowers the AC IMO.

Thanks for the update. It would seem your airflow is not the issue (not the main issue anyway). Adding refrigerant and having the low side pressure drop is telling. Your vent temps for the ambient is not that bad. Essentially if you can achieve a 35°-40°F drop from ambient (at the vents) you're doing pretty good provided High and Low side pressures are within an acceptable window.

'Solar Gain' is always a battle for us that live in the Sun Belt. You can add an Aux Fan (Pusher fan for the condenser) to help with low vehicle speed cooling.

My best 'guess' about your system (looking at the low and high side pressures) is that you have too much oil (PAG 46) in the system. Too much oil (a significant amount) will not hurt the system...but takes up system capacity that should be occupied by refrigerant.

Short of evacuating the system....having it flushed and starting anew.....it would be difficult to fine tune the mixture at this point. Your current vent temps are not bad and its probably not worth 'chasing' the last few degrees that could be had by starting over. IF you are relatively comfortable with what you have now....then go with it until some other component needs replacing. Then recharge the system from ground zero.

 

[uscmas412]

Thanks flint, definitely an asset to this forum! I’m still getting mixed results, ultimately if it’s > 90 degrees out mid to upper 50s dash temp is all I get.

Today I removed the blower fan, inspected evaporator with a camera and cleaned/flushed the evap. It was honestly fairly clean to start with. No noticeable drops in temp. Idled in a shaded garage after it was cool and I could get 55 vent.

Shoved a piece of cardboard into the engine fan at op temp, yup she’s good.

Only due out before I evacuate and recharge, when I checked belt tension I noticed AC belt is aftermarket grooved. I don’t think this is the likely culprit but for sanity sake seems like a cheap way to rule it out.

Original:

Evaporator and valve
All refrigerant lines (to my knowledge)

Replaced ~8 years ago:
Condenser (fins looks clean, minimal surface rust on mounts)
Drier

New:
Denso compressor
OEM idler
Radiator (almost anything coolant related has been replaced with engine rebuild or within past 5k miles)

Only other gotcha, that turbo/downpipe puts out heat (400+) opposite the firewall from the evap. The low pressure line is shielded with reflective heat wrap. Given my idle vent temps, I think this a non-factor.

Edit to add: no foam between fan shroud and TYC radiator. On the shortlist but prob not a factor.

 

[uscmas412]

Because I can’t leave well enough alone, I can get 39 degrees dash temp runnin the piss out of the engine in neutral WITH a sprayed down condenser. In the shade, hood open. 88 ambient.

Let it idle, dash temps climb 10 degrees. Spray condenser again, temps drop 8-10 degrees.

As another point of measure, my wife’s 2020 will do 40 degrees dash in full sun after being heat soaked.

 

[mudgudgeon]

Because I can’t leave well enough alone, I can get 39 degrees dash temp runnin the piss out of the engine in neutral WITH a sprayed down condenser. In the shade, hood open. 88 ambient.

View attachment 3661008

Let it idle, dash temps climb 10 degrees. Spray condenser again, temps drop 8-10 degrees.

As another point of measure, my wife’s 2020 will do 40 degrees dash in full sun after being heat soaked.

Seems maybe your engine fan ain't all that good then?

 

[flintknapper]

As another point of measure, my wife’s 2020 will do 40 degrees dash in full sun after being heat soaked.

Yes, but the newer vehicle has a parallel flow condenser. More efficient.

 

[uscmas412]

@landtank I purchased this blue hub through WE but I think it’s your science. Any help would be appreciated!

There’s 12k miles on the clutch and OEM fan. Matched belts are OEM and have a couple thousand miles.

Is there a way to measure fan output at specific RPM? I definitely feel it pulling air at idle.

 

[uscmas412]

Thanks for the update. It would seem your airflow is not the issue (not the main issue anyway). Adding refrigerant and having the low side pressure drop is telling. Your vent temps for the ambient is not that bad. Essentially if you can achieve a 35°-40°F drop from ambient (at the vents) you're doing pretty good provided High and Low side pressures are within an acceptable window.

Yes, but the newer vehicle has a parallel flow condenser. More efficient.

I’m not against this route, saw another post on my research that mentioned parallel flow.

 

[landtank]

@landtank I purchased this blue hub through WE but I think it’s your science. Any help would be appreciated!

There’s 12k miles on the clutch and OEM fan. Matched belts are OEM and have a couple thousand miles.

Is there a way to measure fan output at specific RPM? I definitely feel it pulling air at idle.

Not that I’m aware of.

 

[flintknapper]

I’m not against this route, saw another post on my research that mentioned parallel flow.

I think I recall someone making a Nissens 94184 work (a few years back).

Might search that out.

 

[uscmas412]

I think I recall someone making a Nissens 94184 work (a few years back).

Might search that out.

View attachment 3661200

Ordered that along with an oring kit, comp oil, drier, Nylog and belt tension gauge. Picked up the air vacuum at HF on sale.

Interestingly, Nissens advertises this 94184 as suitable for the 80 series. Hopefully I’ll report back Monday with cold air!

 

[flintknapper]

Ordered that along with an oring kit, comp oil, drier, Nylog and belt tension gauge. Picked up the air vacuum at HF on sale.

Interestingly, Nissens advertises this 94184 as suitable for the 80 series. Hopefully I’ll report back Monday with cold air!

View attachment 3665359

Interested to follow this....so please DO report back when finished. Though my system is currently working very well, at some point I will want to replace my condenser and I would like to upgrade to a parallel unit.

IF the Nissens is a mostly 'bolt in' replacement with no real issues, it would be good for the community to know.

Thanks, Flint.

 

[uscmas412]

I had my system evacuated and then tested out the pump. Pulls vacuum and holds ~29. I didn’t suspect a leak but I’m learning as I go.

I have a Delta @Delta VS front bumper. I think there’s enough clearance to remove the drier w/o removing the bumper, but the innermost (towards engine) line would be a challenge.

I’m assuming the bolt size on the condenser lines is consistent at the drier?

Removing the battery and tray seems like the safest bet at good contact and visibility.

Tear down starts tmrw AM, hoping USPS is on time with the drier and oil.

Here’s the photos from beneath:

 

[Gascan]

Earlier this year, I replaced every major component of my A/C system (compressor, condenser, evaporator, expansion valve, dryer, evap to firewall a/c line - because one of the two bolts corroded & broke in the threaded end of the line); I had already added an auxiliary electric fan to provide extra cooling at idle speeds prior to this. Recharged the system by weight.
Unfortunately, I don't have a thermometer to measure the vent temperature right now (gave it away to someone who needed it and haven't had a chance to buy a new one) so I can't provide you with the temp delta but the end result is night & day to the way my A/C ever blew during SW Florida summers. Cold, crisp air as soon as I start the engine and only gets better from there.
I think the biggest contributor in my case was that the evaporator fins had begun to rot/corrode and it wasn't up to snuff. Seeing as how you're already replacing damn-near every component, may I suggest you put in a fresh evaporator while you're at it.

 

[uscmas412]

Earlier this year, I replaced every major component of my A/C system (compressor, condenser, evaporator, expansion valve, dryer, evap to firewall a/c line - because one of the two bolts corroded & broke in the threaded end of the line); I had already added an auxiliary electric fan to provide extra cooling at idle speeds prior to this. Recharged the system by weight.
Unfortunately, I don't have a thermometer to measure the vent temperature right now (gave it away to someone who needed it and haven't had a chance to buy a new one) so I can't provide you with the temp delta but the end result is night & day to the way my A/C ever blew during SW Florida summers. Cold, crisp air as soon as I start the engine and only gets better from there.
I think the biggest contributor in my case was that the evaporator fins had begun to rot/corrode and it wasn't up to snuff. Seeing as how you're already replacing damn-near every component, may I suggest you put in a fresh evaporator while you're at it.

I’m not against a new evap by any means, but this is my DD. I have all the equipment now, so if this round of new parts doesn’t fix the problem I know where to go next.
To your point, the kit I purchased from rock auto has a new expansion valve…so I could pull the evap and clean.

My problem is (I think) I don’t great heat exchange. 85 degrees in the AM I get 40 at the vent. 95 in the pm and I’m lucky to get 58 at the vent. The low pressure line to the compressor has been cold and has condensation.

 

[uscmas412]

Doing this live while I wait for USPS to deliver drier. Nissens condenser is in. Took 2 hours taking my sweet time cleaning bolts and checking other areas.

The build quality compared to the Denso I took out is lacking. Time will tell how it holds up. Here’s the new Nissens on top of Denso for comparison.

And side by side

The finish was cracked out of the box at the PS joint, I hit it with the rattle can.


However, it is 100% drop in. Also includes the top mounting brackets and hardware. The bolts for the AC lines provided are not long enough, so make sure you have OEM. Mine were corroded…parts washer and Nylog seemed to do the trick.

The drier was easily removed by taking out the DS headlight which is cumbersome with the Delta front bumper. I probably will not reinstall the bottom most headlight housing bolt.

Nissen condenser installed:

 

[uscmas412]

I decided to skip the evap and expansion valve for now. Here’s the listing from purchase in 2015:

 

[uscmas412]

During install, the AC lines did not match up on the DS. The condenser lines bend easily, almost too easy IMo.

Slight tug towards the DS wheel and it mated up well.

 

[uscmas412]

If you take the DS headlight out, may be a good time to add something abrasive resistant to the ac line going towards the switch in front of battery. I noticed there was protection that had decayed.

 

[uscmas412]

Drier replacement is not bad, seating new o-rings from underneath is the worst part. Make sure you have a pick tool like below. Best do do this directly beneath drier. The kit had the drier with two orings attached. I lost one, but luckily there were more in the kit (prob enough for the entire AC system).

If you tension the drier metal band, it will hold drier in place so you can dry fit and check fitment. Be sure to look at drier from the front of the vehicle for clearance. I added ~2oz of oil to drier before bolting down.

Here’s what I took out (Denso IIRC) vs the four seasons kit and part #