Ac door operation and diag

[obijuank5]

Got some time this evening to get a look again.
It’s 84 feels like 94 right now and these are the pressures.
According to the ac pro chart I found these pressures are not far off but the high side appears to be low.


It’s sweating it’s ass off but so am I.
61 degrees from a temp probe in the evap fins.
Set to max recirculate.
Both sides of evap are wet and the one to the compressor. Condenser is hot on both ends.
Compressor isn’t short cycling.
An external condenser fan brings down the high side a little.
I am now pretty certain my doors are adjusted correctly for 12 and 17.
I didn’t have any time to investigate how to force close all external air from getting in. That’s something I really want to do and maybe permanently.

Thank y’all for trying to help my dumbass. This is my first AC rodeo.

 

[obijuank5]

New parts:
Sanden compressor sd7h15 model 4711
That line assembly to the compressor
Hard line from evap to condenser
Condenser
Evaporator
Orifice tube
Drier
134a compressor cycle switch thing
Blower motors front and rear
Vacuum selector switch on the control board

PO said he replaced the expansion valve on the rear air and it does appear new.

 

[Wes Harden]

1 thing you can do that might help, is insulate the tubes and accumulator at evaporator. Doing this will help the evaporator stay cooler in the plenum. I did this to my 01. The factory insulated the accumulator.

The high humidity really make the system work. Keep using the condenser fan it will help at slow speeds and long stop lights. The compressor will only cycle if the low side drops below 28-32 psi, or the high side goes 450-500. If you were in the 45-50 and 250-300 range it won't cycle

edit gmt400 blower motor upgrade for @25% more air flow.

 

[obijuank5]

I’ll try that insulating. Definitely couldn’t hurt.
I don’t think the condenser fan influenced air temp much if any.

I did do the gmt400 blower btw.

 

[Wes Harden]

personally I don't think the new parallel flow condensers are big enough for our squares with dual air. I have no proof just my opinion, formed from a few r12 conversions where I did "up" grade to the new style verses just keeping the tube and fin.

 

[Blue85]

It's been discussed here many times. The "universal" parallel flow ones are smaller than the original tube and fin ones by about the same % as the efficiency difference, so not much change (until you need to flush!). I have read some reports of some giant parallel condenser that's as big as the original, but I have no idea what the application or PN is.

With the low side looking high and the high side looking low, it seems you need a smaller orifice or a bigger compressor . If you slow down the blower motor, do those temps get down into the cycling range?

 

[obijuank5]

I’m not sure if the blower motor would change it. Never tried.

This is the condenser. Full width and height and fit in factory mounts.
7013642

 

[Wes Harden]

If I remember tonight I'll measure my tube and fin

 

[obijuank5]

I found this digging around, but not sure what to refine the search as so I can get one. Google kinda sucks now and tbh, the all look the same and that has got me in the past.

Maybe a 90s f150 seems similar by the specs.
.067 instead of mine as a variable.

For r134a run the blue Ford orifice tube, it seems to match the R134a pressures better.

 

[Blue85]

The slower the blower fan, the lower the temp in the evap will be. It will also lower the high side pressure from having less heat in the system.

 

[Wes Harden]

so my tube fin condenser is 28"x 16.5-17". Maybe different with pre 81 core support.

The normal r12 white orifice tube is .072mm. The blue at .067mm is good compromise for r134a in a r12 system conversion, since it is a smaller molicule.

 

[JoshHefnerX]

There is so much good info on this forum. Wish there was some way to categorize and catalog info like the above for easy reference.

 

[obijuank5]

So I shotgunned the ford .067 orifice tube with no change. The high side pressures were still low so I bought a replacement compressor and I’m gonna try and throw that on this weekend.


Then after that it’s a new R4 compressor.
Every year.

 

[JoshHefnerX]

You're doing logical steps. You'll get it figured.

 

[Blue85]

Then after that it’s a new R4 compressor.
Every year.

The R4 works great until it gets noisy or starts to leak. I thought AC Delco had some improvements for a while, but I don't know if you can get a good one anymore. The factory ones were good for 10 years+, so something went wrong at some point.

I made a tool from an old R4 outer housing, that let me press off another housing. Then I would change the outer O-rings and put it back together. Then after 5 years or so, it would start to get noisy, and I'd look for another. I always suspected it's the thermal cycles of a steel jacket sealed to an aluminum block that makes them leak. I wonder if there's some magic goop you could coat the O-rings with that would hold that seal for longer...

I'm currently running the tiny scroll compressor that looks like an R4. It's dead quiet, but the cooling isn't very good.

 

[Wes Harden]

Can't even a good fridgedair A6 anymore. Maybe one or 2 on some barn find or another.

 

[obijuank5]

So this does make me feel better but also worse.
I found steel gasket material literally blocking the discharge port. That’s good and all but I feel like this system is now full of metal debris and I’ll have to do it again.
There is a spot of impact on the piston head but all the walls appear ok and the oil that is still in it appears not glittered.

I know I can’t flush the parallel flow condenser but I should be able to flush the rest. The orifice tube was glittery when I took it out but I was praying it was from the last compressor. shit.

I got two options. ANOTHER condenser and a flush or just put it on and send it.

 

[Wes Harden]

In the new condenser camp, flush lines.
That gasket material will plug up another orifice tube if left in there.

Do you remember the compressor brand ?

 

[obijuank5]

In the new condenser camp, flush lines.
That gasket material will plug up another orifice tube if left in there.

Do you remember the compressor brand ?

It’s a genuine sanden.

 

[obijuank5]

New condenser, drier, orifice tube, and flush solvent. This some boolshit.
Used that rock auto 5% though. Even with tax and shipping its cheaper than my first call oriellys account.