Hi. My car is XJS '91, right after the facelift.

The AAV on my car went wrong, and I am thinking of replacing it with a new one.
According to the JDHT parts list, the correct AAV for my car is EBC3819, which is quite expensive like £284.64.
If I could use EAC2273 or EAC4438 it would be much cheaper.

Has anyone experienced replacing an AAV with a one with a different part number?
Or any suggestion?

I have already read the AAV theory on jag-lovers.com anyway...
but still not sure if I could use other valves.

Many thanks in advance.

 

I rebuilt mine with the use of Volvo Marine thermostat bulb. Took me a day to dance around with little details, but overall it went smooth.

 

Does anyone have the correct part number and rating of the Volvo thermostat bulb, that I can use in my 91 Jaguar ( pre-face lift) V12 XJS aav re-build, also who sells them? I see many listed on marine engine sites but I really need the correct one to use. Thank you in advance. Graham

 

Back in the day when I had waaaaay tooooo many V12's, I had spare valves to burn, I haunted wrecking yards.

I would swap PreHE for HE, and so on, as required when one went AWOL, and took absolutely NO notice of part numbers.

They are a valve that is open when cold and shut when hot, not rocket science in any language.

Eventually I got sick of it and removed them all, and used a simple solenoid vale, or 2, and manually switched it inside the cabin, so simple and so efficient.

That is my dealings with that lovely piece of alloy at the rear of the LH head. We have 9 in our group now without that AAV.

 

My experience with the AAV is thus. I'm first assuming you have a v12 even though you have a facelift model which of course you could have gotten with a v12 or a 6. I have both a coupe 82 and a convertible 91. With these things costing a C note easy for a good used one I opted to put the one I could find on the 91. It worked. But HOW it works leaves a little to be desired. When cold, the engine starts and revs up to 1100 rpm and takes close to a minute to heat up and lower the rpms which means if you want to go right away you'll get a bump upon shifting into drive or you wait till it warms and lowers (which you really should do) so, if you don't want the bump and high idle pulling you along you have NO choice but to wait. On the other hand on my 82 the AAV was frozen closed (which is the equivalent of stopping up the vacuum inlet in the air filter housing which eliminates the AAV completely), so it was like the engine never had an AAV AAAND, I never had an idle problem with that car. It would start and every time idle at 600 rpm right off. I don't know why but I'm just counting my blessings. After putting the AAV in my 91, I won't put one in my 82. If your car will idle properly like my 82 then unless you have to have everything "proper", close off the AAV and " figeddaboudit" Bud P.S. a little rubber ball works perfect!

 

I'm with you guys on this one for sure.

I did battle with the AAV as well.

Given another chance....er...given another V12....the AAV gets tossed over the hedge at the first sign of trouble

Cheers
DD

 

The 1990 or so vintage Toyota inline 6 had a similar valve. Maybe it would work. They call it a "idle control valve".

Grant's solenoid valve could benefit from:

AutoSpeed - $25 Temperature Controller and Display!

Completely programmable and makes a decent temperature gauge as well

It could also be applied as a fan control, alarm ... whatever.

 

Yep.

Back then we were all looking for a thermo switch with low enough values to do the "auto" bit, but since they are mostly thermo fan switches, the temps are way too high for this one.

I did find a Diesel Toyota Hi Ace that had a switch in the bottom radiator tank, about 55c from memory??, but getting hold of one was damn hard.

My V12's are gone, and missed, and the others are quite happy with the small switch to cold start the beast, and anymore thought is simply invading our drinking time, cheers.

I have a "Word doco" on the rebuilding of them (Grant's way), that I did a loooong time ago, and another on replacing the thing. If anyone wants it/them, PM me with your email address and I will oblige.

 

Many thanks for the response guys, actually I posted this more than a year ago and have forgot about it...
I eventually bought one for pre-facelift model and it is working fine, as Grant says. Of course the time needed for valve to close will be different from the original, it doesn't matter so much.
In addition, I changed the air intake system and the air flow is not the same as original any more, it is no use worrying about the AAV difference :P

 

Do you still need that? I can search for original part number in my mail archives.

 

Yes I do, I would like to find other part numbers also for alternitive AAV units or a place that will rebuild it with the volvo thermostat for my 91 Jaguar xjs v12. thank you Graham.

 

New Genuine Volvo Penta Thermostat Kit 3831426 | eBay

 

What are these beautiful intakes!?!?
Where did you get polished throttle table parts like this?
BTW, your English is very good

 

Hi Mish_Mish, sorry for the late reply.

This intake kit was listed on ebay by a British guy, I bought so called "DIY kit", which was not screw-on, they say some work was left for me to do, actually a lot was left!
I bought the air filter box separately in Japan. They were made in China, so they were cheaper in Japan than in the US or the UK, you know we live closer to China
Anyways they cost much cheaper than the FasterJags kit and have better effect I think, for mine don't allow to inhale hot air.

I removed the throttle tower assy from the engine and just brushed it with a stainless wire brush. It is made from aluminum, so it was easy to make it look like this. Of course it is not mirror finished, but it is shiny enough to surprise someone who see inside the bonnet

Thank you for the compliment for my English, I can write but speaking is not good enough still!