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LG LFX31945ST French Door low side in vacuum capillary tube issue?

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LG LFX31945ST French Door

Hi I got this 2014 used LG fridge in excellent condition the woman said it needs a compressor.
Found service valves have been brazed onto compressor suction line and high side on the filter dryer stub.
No pressure was in the system and saw dye had been added.
Used black light and saw dye in the condensate drain pan water.
Checked evaporator in fresh food section and saw dye all over the coils and dripping into drain pan.
Looked like the aluminum to copper transition crimp was the leak.
Checked freezer evaporator looked fine no sign of dye.
Ordered brand new evaporator assembly since it comes with the defrost heater and sensors and wire harness all attached so decided to go ahead and replace freezer evaporator at same time as I read the defrost heaters get weak over time and I had it all apart already.

When i removed the black tape sealant that they wrap around the brazes to cut the tubing i noticed what looked like damage to the capillary tube just above the braze it felt like someone pinched it with side cutters but looking closer it looks like a factory made pinch off crimped on the capillary tube so its like a tiny orifice made with some type of tool.

Looked at the freezer capillary tube and has the same tiny crimp mark you can feel it with your fingernail.

I wasn't sure if last person working on this did that or if it was factory made crimp.

I cut and filed and used tiny pick tool made sure cap tube was open (below these tiny crimps).

I used Stay Brite 8 to silver solder in the two new evaporators, pulled vacuum for 1 hr and charged with 134a 5 oz.

System is running low side in 20 in hg vacuum and High side 110 psi left it overnight running and fridge is hot inside.

Pulled power cord pressures do not equalize at all low side stays in vacuum with power off.

Obviously a restriction but does anyone know about these tiny crimps are they supposed to be there in the cap tubes?

Or possibly the drier is clogged maybe the last guy used sealer dye to stop the leak and clogged either the cap tubes or drier with it.

PS this is the LG that uses a reversing valve by the linear compressor to direct the flow to each evaporator.
Compressor sounds good and no flashing error led on main board and no errors on front panel.


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I posted this question on another help board and this guy replied to me.

Posted by UmmScott

YES....LG puts that pinch in the cap tubes from the factory.

From what Ive been told, they put that pinch in there so you don't hear the sound of refrigerant flowing/equalizing during the off cycle. 
Lg said to remove said pinched area and that should take care of the restriction. 

That was me talking to LG tech support a few years ago. Idk how i even made it that far because you're supposed to be factory authorized...etc...blah blah blah...

He said on some units they over-pinched that area and caused too much of a restriction OR something gets stuck at the pinch causing a complete blockage

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I think the 3 way valve is defective. 
I de-soldered the cap tubes and put compressed air on the high side and the freezer cap tube blows strong but fridge was very weak flow. 
Re-soldered them up ran vacuum for over an hour.
The filter drier is marked UV Drier so that was replaced in Feb 2018 (confirms what LG told me about this serial number that it was recharged and cooling normally).
When I recharged it the pressures were normal about 2 psi low side 100 hi side and freezer was cold overnight but fridge was barely working evaporator was slightly cool to the touch.
Watched the pressures and occasionaly low side drops into about 20" vacuum so I assume that is when it tries to flow to the fridge evap and it either jams up the valve or the cap tube is plugged up.
So either the cap tube is plugged up or the 3 way valve is only allowing flow to the freezer.
I was going to cut the 3 way lines and just bypass the valve recharge it see if they both cool before investing $120 in a 3 way valve.
The solenoid it clicking on the valve actuator when I plug it in you can feel it trying to operate the 3 way valve but I read on these forums the internal valve jams up.
What would happen if I just bypass it and leave it piped for constant flow to both evaporators?
Will the fridge start giving error codes since it cannot vary the temps?
If I set the set-points to the coldest settings for both freezer and fridge would that prevent it from setting codes?

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Did you ever figure this out?

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