Air-con TXV O-rings

[white exec]

Does anyone know the sizing of the two sizes of O-ring for the TX valve?
.

Have taken delivery of a
Mahle Behr AVE87000P, which comes without the rings.

It's equiv to O.E. 6461.J3 (NFP, and Parts not showing the O-rings),
and same as Vemo V15-77-0003 and Valeo 508690.

Measuring the device isn't straightforward, as there are a couple of possible positions for the seals.

Thanks.

[Jaba]

I can find this out for you when I can get into my store and size them up in a day or two.

[white exec]

Aha! The man who can!
Have put out a lot of feelers on these, with no size-result back yet, so hope you can find the dimensions.
Looks to be 3 sizes of ring — a large and a small on the hose side, and two medium ones (the same) on the evap side.

It's a job described in a good few places, but not much in the way of photos, so fully intend to remedy that.

[Jaba]

Aha! The man who can!
Have put out a lot of feelers on these, with no size-result back yet, so hope you can find the dimensions.
Looks to be 3 sizes of ring — a large and a small on the hose side, and two medium ones (the same) on the evap side.

It's a job described in a good few places, but not much in the way of photos, so fully intend to remedy that.

Located my stock and here are some pics. You need 1 x #6 + 1 x #10 for the external connections and 2 x #8 for the evaporator side.

[white exec]

Hi Jaba,

Thank you for finding all those - perfect!

After a lot of legwork, I also managed to get an email confirmation from this company https://www.swisclima.ch/en/fans/g/4010/art/16808
that the sizes are:

I.D. x thickness (mm)
7.65 x 1.78
10.82 x 1.78
14.00 x 1.78

with all three in this HNBR kit from Amazon:
https://www.amazon.co.uk/Kissral-Assort ... 386&sr=8-1

Now having fun in the footwell, driver's seat out and lots of LHD bits in the way. Rain stopped play several times this morning, so hoping for some progress tomorrow.

Thanks, again.

[white exec]

Am really struggling to remove the old TXV...
LHD
Pipes off ok in engine bay.
Lower steering shroud removed for better access.
Have managed to loosen the two topmost unions which screw into the aluminium TXV. PlusGas worked well there.

The two lower unions (hose side) won't budge though.
PlusGassed several times, but gravity not helping get the fluid up into threads.
Have decent flare spanners for all the joints, but unbelievably tight.
Main problem is stopping the body of the TXV from twisting, and damaging the Cu pipes.
Lots of toot in the way, as it's the driver's footwell...

Soaking again overnight in PlusGas.
Tomorrow will try a hot air gun on the TXV, which should (should) expand more than the brass unions.

QQ:
Do I need to remove the large oval rubber grommet (that sits in the firewall) in order to free up and lift out the two connecting pipes? Yank the grommet out through engine bay?

The engine bay hose-side pipes entering the TXV need to come out first, for the valve to be dropped down and out. The upper two are fixed into the evaporator, so won't be moveable.

I'm guessing that removal of the rubber grommet is the key . . . What's the best way to do it ?

A rotten job, so far, so any advice really appreciated.

[white exec]

Morning three on the job, and some welcome progress...
- Engine-bay side of the large neoprene grommet pulled away (in small pieces) to allow the large and small pipes wiggle room. Will refurb later.
- Managed, finally, to undo the two lower (hose side) TXV unions - both v.tight, and undid with a loud crack. Valve body gripped with a pair of moles, wedged in position. Flare nut spanner extended with another, for extra leverage.
- With all four unions undone, a struggle to pull out 3 of the 4 copper pipes - firmly adhered to their O-rings, and O-rings to their seats, so didn't want to twist or pull out, even after some penetrating oil.

Old TXV now out, and definitely seized and cruddy around the slider-valve.
I think there has been moisture in there; dryer was the original, so never replaced in 29 years.
TXV exactly the same part as the new one: an Egelhof (new one is for R134a).

New one will go on tomorrow. Had quite enough contortion for today...

[Jaba]

Well done for getting it out, its always a struggle! As condensation does form on the outside of the TX valve due to its running temperature its worth thinking about some lube on everything as you reassemble. Also the more you can insulate and seal it externally the less condensation there will be and the more efficient the cooling will be (theoretically speaking anyway).