Aircon Schrader valve

[Lotus17]

Hi does anyone know what size type of Schrader valve is used in the low pressure port on the 2014 polo bluemotion,or the correct vw part number. I need to change mine
Thanks Neil

[RUM4MO]

The official VW Group part number is 8E0 820 855 and it will be M8 fine.

If you check the diameter of the threaded section of the dust cap, you should find that it is M8 - or check the I/D of the Low side, much easier, and it should let you know if it is close to 8mm, the thread will have a 1.0mm pitch.

I'm guessing that the original insert has been damaged by over inserting the fridge line valve depressor - or if not does that valve insert not just need a quick "flick" or "jab" to encourage it to reseat correctly.

Edit:- they are obviously a standard part, so maybe a fridge/chiller spares place could supply you with one/some - though you would need to make sure that they sold you an M10 version as from memory commercial fridge/chiller systems use a smaller size.

Edited many times, should be correct now!

[RUM4MO]

I've updated that last posting now that I've checked the car and found that the VW Group parts listing, or the additional parts description is not, in this case correct.

I think that I discovered this in the past when I needed to buy a new Low side dust cover for the Polo, I used the listed part number for a 2011 Audi S4 instead - and that fitted that Polo perfectly!

I've updated the initial posting and added another posting.

[RUM4MO]

Okay, 3rd attempt to get this right!

Low side, used for charging etc, valve insert is VW Group p/n 8E0 820 855 and it is M8 fine which will be 1.0mm pitch!

Sorry for the confusion!!

[Lotus17]

Thanks for taking the time to reply , next question is where can I get one from please.

[RUM4MO]

I've never had to replace one, any VW Group dealership would either stock them or order one in for you, most online sellers will be selling maybe an unknown quantity in terms of suitability for use with R134a or general quality. There will be refrigerant equivalent to motor factors in most towns, and they should be selling suitable ones for use in these car AC systems.

Again, why do you think that it needs replacing, have you sprayed a leak detector spray - or soapy water on that filling port and seen bubbles being created?

[Lotus17]

I saw bubbles after putting in Stp leak seal , I also wet the top of the inlet with saliva as you would with a tyre and it kept popping.

[RUM4MO]

Have you tried seeing if that valve insert can be tightened down any more as its body seal might be causing this leak.

How much of a leak did you have that forced you to use some system leak stopper, my wife's Polo was recharged early July last year and started logging low pressure fault codes in late October. I have just had it recharged and again I can't find any leak sites, my next plan is to remove the front bumper for better access to the condenser - and I have thought about spraying a bubble leak spray into both the service ports to check these valve inserts.

[Lotus17]

I've just some special no gas loss Schrader valve replacement tool . The bubble was slowing. I had it regressed in May they said 'there was no gas in it ' they did a pressure test on it for 10 minutes and it held perfectly which it would if there kit was sesealing the low pressure port . I've regased it myself and it's been fine for weeks then it just stopped cooling.

[RUM4MO]

Good enough, I've seen these tools but never seen anyone actually using them.

[Lotus17]

I'll give an update about the special removal tool

[Lotus17]

I will need to open up the slot to fit the Schrader valve

[Lotus17]

The new Schrader valve is in ,the old one was hard to get out ,so time will tell.
The genuine valve was £18 A bit salty .

[Lotus17]

The valve is changed the special removal tool didn't fit the notched piece was to narrow to fit on the Schrader valve, so I bought a normal removal tool and finally got it out , I've regassed it and all seems good . I do wonder if some leaks are from a leaking valve and gets overlooked .

[RUM4MO]

Good enough, after you mentioned this I noticed that most at least online sellers were asking a lot of cash for these inserts. In my experience the commercial or at least high performance fridge business tends to use normal sized valve inserts and they only cost smallish money, I don't know MAC systems are trying to be different, and I'm talking about systems that use higher pressure gasses than R134a.