Out of curiosity....

[chrismsullivan]

Let's just say that if you weren't convinced that your AAV was fully opening and closing on your M110 D-Jet and you were thinking about buying a new one and noticed that they are very hard to find, but also noticed that there are plenty of the AAV's available online from the K-Jet setup...

It's almost a given that the newer version found on the K-Jet would bolt straight up to the block, given that the layout is the same. But, would the AAV operate as it should on the D-Jet setup compared to the older version? Would it be as simple as changing a bit of the pipework to and from the intake manifold to accomodate for the different layout of the intake and output pipes of the different AAV?

Do the two AAV types have different flow rates, or different open/closed ratios?

[vlv8vic]

Would love a few links to the K-jet ones please.  Best i could find is $350US but they don't seem to ship to AU.
Thanks,
Japes.

[chrismsullivan]

Would love a few links to the K-jet ones please.  Best i could find is $350US but they don't seem to ship to AU.
Thanks,
Japes.

Just jump on eBay and do a search for Mercedes auxiliary air valve. You'll find some for around $150.

[vlv8vic]

Ahh yeah the one from the states? I can only see the one to fit the 280se K-jet.  Second hand worries me a bit - $150 plus postage is a bit of a gamble for something I might have to replace in a year or who-knows.  Probably chasing new so perhaps I'm stuck with the higher price.

[chrismsullivan]

Here's a reco'd one for $88
http://www.ebay.com.au/itm/Mercedes-W107-W116-Auxliary-Air-Slide-Valve-0280140032-/320753436028?pt=Motors_Car_Truck_Parts_Accessories&hash=item4aae65057c#ht_500wt_922

You could buy about 4 of them for the price of 1 new one. Might be worth the gamble?

Anyway, back to my original question. Would one like this fit onto the M110 d-jet configuration?

[vlv8vic]

thanks for that - i guess putting in 280 was getting me less search results (assuming that it's the same thing as the 450......(?)

Apologies for the hijack.

[chrismsullivan]

thanks for that - i guess putting in 280 was getting me less search results (assuming that it's the same thing as the 450......(?)

Apologies for the hijack.

No worries at all mate! It's all kinda on topic. 

[koan]

Here's a reco'd one for $88

They are a wax thermostat, reconditioning probably consists of cleaning up the outside and flushing with carb cleaner, doubt the wax is replaced which is what needs to be done.

Saw a cross section of A K-Jet AAV somewhere but never found it again, there is small o-ring that seals the wax compartment, think the wax leaks out or changes composition over the years.

Waxes are odd, when they melt their volume increases 10 to 15%, thats how thermostats work.

koan

[WGB]

AAV's are very easy to test - just put the copper bulbs in hot water and see what happens.

The internal slide should be wide open at room temperature and fully closed in hot (near boiling temperature water).

Here is a picture showing a new K-jet one closed and the old one only partially closed in the same cup of hot water.



Bill

[chrismsullivan]

Thanks Bill.

I've previously pulled the AAV off mine (it's not the same as the ones pictured). It didn't open all the way up when at ambient temperature and closed to a little less than 1mm when it was introduced to a cup of near boiling water.

Despite a clean out and some lubrication, it didn't improve much from there; hence my question as to whether the AAV designed for the K-Jet would fit in place of the one designed for the D-Jet.

Cheers,
Chris

[KenM]

Sounds like you need to be the guinea pig here Chris and do the experiment to find out for the general good. I'm curious myself as to why these things cant be pulled apart, seems to me there is an aluminium body and the brass pot containing the wax and plunger and that's about it; but if the wax is indeed leaking out over time it would be impossible to replace successfully, it will be a special mix with specific properties that you would have no hope of replicating.

[chrismsullivan]

Yeah... Maybe you're right. I might try to hunt down a cheap one and see if I can work some magic.

Stay tuned! I've just gotta figure out how to get the car running again first.

[koan]

I'm curious myself as to why these things cant be pulled apart, seems to me there is an aluminium body and the brass pot

I've tried to get K-Jet units apart, heaved and pulled on them with various tools but no success, maybe something that clamps round the top like a collet in a collet chuck would do the job. The chucks and collets I have for the forthcoming milling adventure are not big enough.

if the wax is indeed leaking out over time it would be impossible to replace successfully, it will be a special mix with specific properties that you would have no hope of replicating.

Not sure about, when I was playing with the valve I got onto a guy at a wax factory, most of what they make/sell are perfumed waxes for aroma therapy (!) but when I said what it was for he suddenly became interested and listed waxes they have and their melting points.

The aux air valve doesn't regulate idle speed depending temperature but should be wide open while the engine warms up then suddenly right close off after say 50-70C is reached, as mentioned before waxes expand significantly when they melt. Wax used in radiator thermostats melts at higher temps, typically 85Cand is no good for this purpose. 

If we could get the valve apart it would be worth having ago.

koan

[calvin streeting]

here is a disection of a djet version

http://www.benzworld.org/forums/r-c107-sl-slc-class/1533174-auxilliary-air-slide-valve-deconstructed.html

and somewhere i have seen a k-jet one, i will try and find it.

I found a drawing http://www.benzworld.org/forums/r-c107-sl-slc-class/1533174-auxilliary-air-slide-valve-deconstructed-3.html

is it me or do both apear to use the same wax fitting on the bottom, and also there seems to be a threaded bar on top for adjustment.. intresting.

[chrismsullivan]

That first link is certainly cool. But... I don't think it's from a w116. It's certainly different to the d-jet AAV that's in mine.
Mine has an air input in the side, same base plate and bulb, like the link, and the output comes straight out of the top, with none of the lips seen on the link.
I'm thinking that one might be off an SL series?

The other link is absolutely a k-jet m110.

My thinking is that the bulb, base plate and internals are basically the same between the d-jet and k-jet versions, making install a snap.
Re-routing the air pipes from d-jet to k-jet configuration also shouldn't be too hard.
The only problem I can think of is if the two different AAV's flow very different volumes of air.