Guys I can't seem to find a individual part number for the rubber coupling between the throttle and the plenum T (Part number AJ811188)
See photo.
Anyone know the part number or where to buy ? Worst case I can order an aftermarket silicon coupling.

 

Google shows the P/N as for the whole top hat assy.

https://parts.jaguarpalmbeach.com/p/.../AJ811188.html

Maybe a good local parts guy can get it or sort it by dimensions and see what comes up on the web?

 

You might try NJA3554AA . That is a duct seal that goes between the throttle body and air duct on earlier 4.0 XK8's & XJ8's. Item 6 on the diagram below. I don't know if the diameters are the same or not. (It looks quite reasonably priced - $55 list for what should be a $4.00 part.)

 

Make one yourself with silicone.
Make a mold from plaster of paris.

 

That's a pretty clever idea. Like bathroom grade silicone or something more exotic?

 

You can use RTV Silicone- Just take time not to get any air bubbles.
There are tons of sites where you can get different types of silicone. Pourable and one that we used to import from Japan that was so thin we could soak fabric with it effectively making it ultrahigh temp.

You know that you can get gasket silicone in a easy to apply and economical form than those silly tubes from the auto store? Red RTV Sealant - Blue Silicone Sealant | Silicone Depot

We use a trick to strengthen silicone that no one knows, mix fine sand.

 

BTW- this is the best invention ever.
Allows you to be super precise with application.
And there is no substitute. Used mine for more than 4 years now.

 

The gasket from the earlier cars is a perfect fit.

https://www.jaguarforums.com/forum/x...7/#post1669935

 

I got this of of Amazon to replace my broken rubber adapter. It works great. I had to trim it shorter with a utility knife but it works perfect for this piece. I ordered NJA3554AA at first and it did not work well so i measure both intake and throttle body and found this coupler to be close.

HPS HTSR-325-375-BLK Silicone High Temperature 4-ply Reinforced Reducer Coupler Hose, 40 PSI Maximum Pressure, 3" Length, 3-1/4" > 3-3/4" ID, Black

HPS HTSR-325-375-BLK

 

Please clarify Tracy. You mention it works perfect and then later indicate it's close. One of these is not like the other. What makes it perfect vs. close? Once trimmed it's perfect?

 

The smaller end was a few MM smaller than what I measured on the throttle body but the silicone stretches enough to make a good snug fit. When I used window cleaner it slipped on very easy. The large opening fit snug and with the clamps on both ends it should be leak free. Much better fit than that JAG part that was way too small for the T plenum. The silicon hose will probably outlive the JAG part too.

 

Just what I was looking for.
so part NJA3554AA
is that not a factory replacement?
The silicone unit just fits better ?

 

The Jag part is not a direct replacement it was a part from another car. the factory replacement is the $700-800 complete Y pipe AJ811188. The only thing I saw was they said NJA3554AA fit the throttle body side by measurement. I never found the post saying it worked and installed fine. I purchased it and could not make it fit on the Y pipe. The silicone adapter is the way to go in my opinion.

 

Like tracy keys said. I get the ones from siliconeintakes.com. They're about $12-15
and yes jaguar only sells that piece with the aluminum hat $$$$

 

Just ordered this myself however, it was $46. The one on my 2008 was "toast" splitting into many pieces as the top hat was gently pulled up. Someone had been in there with RTV and tried to patch it up.

 

I found that this piece works as well with trimming and is much cheaper at $15 https://rover.ebay.com/rover/0/0/0?m...2F230632147735

 

NJA3554AA it's not the correct part. The seal is not sold separately that is why it cost $800 to fix this with the dealership plus labor . I ordered the part above anyway and it is definitely not a fit.!

I also ordered the thicker reducer also shown above in this forum from amazon but in my opinion it would not have sealed as well as a softer coupling ...I just thought it was too rigid. It would also have been harder to install and make it harder to align the two intake ducts to the top of the tee.

I was able to find the coupling from Home Depot that worked perfectly. I also placed a hot soldering iron on it and then also on the original part. The original OEM part melted much faster so I know the Home Depot coupling has a higher melting temperature. Cost me 100th the cost at $8 and some cents. I've driven the car now on two four and a half hour trips in hot weather and examined the coupling and it is fine.






This is a photo of the original part from home depot obviously you do not use the metal housing. The two inner diameter sizes are perfect to to slide over the T duct and the intake duct.

 

You misread Tracy_Keyes Post #9, so read it again. He stated: "I ordered NJA3554AA at first and it did not work well..." The coupler he used is HPS HTSR-325-375.

Great alternative from Home Depot!

 

Hi Roger,

I purchased this part and took it to my mechanic who said it did not fit on the Intake (top).
He said it fit ok on the Throttle, (bottom).

Did you have to make any modifications or do anything special to get it to fit on the intake ?

Many thanks.

 

This was a while ago but I know the silicone coupler fit perfect on my car I believe it is 3-1/4" > 3-3/4" size