Sodium filled exhaust valves? Are they standard fitment to S2's?

[LHD_Kid]

I am after a set of exhaust valves and want to get OE spec.

Audi tells me that the same part number listed for 3B/ABY/ADU is also listed for use on early Passats, Golfs, etc, and are not sodium filled.

Is there anywhere I can find proof that OE valves are indeed sodium filled?

It does look like the Audi part number is quoted for multiple cars....

I've trawled the forum but cannot find conclusive evidence, lots of people talking about them though...

Thanks chaps

Chris

Edit: The valves I have been provided with are made by TRW, which I understand is OE for many makers, Audi and Porsche included... This is the Audi number I have : 027 109 611B

[UrS4boy]

I believe that the original fitment 3B, AAN, ABY and ADU (and the 32 V V8) exhaust valves were sodium filled. The PN is supposed to be 027109611B. Not sure what the bins are filled with at the warehouse though.

[AndyP]

I've just checked the receipt from when I replaced my exhaust valves and they were 611B's, couldn't tell you if they were sodium filled or not, I just assumed they were. If I were re-building the head again, I think I'd replace them all with these:-

http://www.ebay.co.uk/itm/2905577457...84.m1423.l2649

Definatley replace them if you're rebuilding the head, check my build thread to see what happens when you don't

[LHD_Kid]

Hmmm... So, Audi send the correct part - as per the number, but we don't know for sure (as said) what the parts bins contain, we don't know 100% if the OE spec is actually sodium or not... We just think it is...

Should I simply use the new valves I have, even though I believe they are not sodium filled?

I like the valves in the link - food for thought...

[SteveH]

Shouldn't you should be able to tell the difference between sodium filled and non sodium by looking at them? I thought the sodium filled valves had a more pronounced neck between the valve head and stem?? The 7A exhaust valves have a small radius between the valve and the stem, more like the look of the inlet valves.

[Pirvu Eugen]

Hy!
Today i will make the test with old valves.
I have oem 7A and 3B valves wich i will cut and put them into water to see if they are sodium filled or not.
The TRW valves are looking the same with the 7A valves i have....also the weight of them is the same. The 3B valve is lighter with aprox 2grams then the 7A one.
I have also the TRW valves new...but i dont want to destroy a new valve though.
I will let you know the test result.
All the best!

[MrVain]

I cut my old valves in half and they were filled with sodium! ABY 1996 engine

[Pirvu Eugen]

I susoect will be the same with the 3B also. Anyhow...the 7A valves are looking diferent as the 3B ones i have.

[SteveH]

7A aren't sodium filled, I'm pretty sure of that.

[4WheelDrifter]

Just weigh the valves, it's pretty obvious if they are sodium filled, or not.

My '91 3B valves are sodium filled, my 7As are not. I'm fairly sure I noted the exact weights of each somewhere.

[Thuppu]

I cut my old valves in half and they were filled with sodium! ABY 1996 engine

A pic of that would be interesting to see.

[Wheeljack]

A pic of that would be interesting to see.

They are definitely visibly different, with the sodium valves having the telltale 'tulip' shape for the extra volume. And also anyone who disposes of these SHOULD be cutting them and soaking them in water to react the sodium to protect anyone further down in the recycling chain from injury. They will make nice little bubbles when thrown in a bucket of water.

And, if you are building a performance engine with high rate springs, increased redline, etc., you will NOT want to use the sodium filled valves. The reduced cross sectional area of the neck, due to being hollow, is a major weak point and prone to dropping the valve and causing some serious damage. You'll want some decent inconel or similar exhaust valves in this case.

[Pirvu Eugen]

Ok!...soo as i promissed!
The 3B valves with the pn. 027 611B on the stem....ARE sodium filled valves.
The 7a with pn: 027 611D are NOT.
In the pictures you can see.
First is ...starting from left: 3B new, 3B old, old 7A and TRW 33050 new.
The next is the 3B new.
Next is the 3B old, then the TRW new, then the 3B and TRW together, then the 3B and 7A old cutted in half and the last is the 3B one alone.
The 3B one has fizzed more than 10 minutes into water.
Ahhh...and: The new 3B valve weights 49.1 gramms, the old 3B has 48.4, the old 7A has 51.7 and the TRW is 51.
I am pretty sure that the TRW is NOT sodium filled.
Hope this helps!
All the best!
Eugen

[LHD_Kid]

Ok!...soo as i promissed!
The 3B valves with the pn. 027 611B on the stem....ARE sodium filled valves.
The 7a with pn: 027 611D are NOT.
In the pictures you can see.
First is ...starting from left: 3B new, 3B old, old 7A and TRW 33050 new.
The next is the 3B new.
Next is the 3B old, then the TRW new, then the 3B and TRW together, then the 3B and 7A old cutted in half and the last is the 3B one alone.
The 3B one has fizzed more than 10 minutes into water.
Ahhh...and: The new 3B valve weights 49.1 gramms, the old 3B has 48.4, the old 7A has 51.7 and the TRW is 51.
I am pretty sure that the TRW is NOT sodium filled.
Hope this helps!
All the best!
Eugen

Thanks Eugen, this makes interesting reading.... but....

This is worrying and confirms my worst fears...

If you go to Audi, armed with the correct part number for S2 valves - which were originally sodium filled, they will smile and happily sell you (under the same part number) valves which are NOT sodium filled - made by TRW....

[Pirvu Eugen]

I dont know what to say Chris...but...i ordered mine from Aelred....and he sent me the valves in the oem package and i am pretty sure i received the sodium filled ones.
I will speaq with Aelred...and, iff i can get another valve....i will cut in half one i have allready...but..i am pretty sure they will be sodium filled.
I dont know..iff these are better or not...but i think that Audi has put them into these engines for something.
Will be easy for them to put there some valves...but they didint...sooo i will put my trust into their knoledge.