I am in the process of changing out the o-ring in the passenger side Norma connector on my 2001 XK8 convertible.

Miraculously I was able to disconnect my Norma connector to the octopus hose on that side with out breakage or any real issues. I carefully fished out the o-ring with a hook with no sharp edges, and it was literally falling apart.

I have seen multiple sizes mentioned for this o-ring in this order of frequency on this forum:

1 1/6 OD 13/16 ID 1/8 thickness
1 1/6 OD 15/16 ID 1/8 thickness
10mm

Apparently, there are also different materials that can get the O-ring in:
Buna rubber
Viton rubber
Neoprene
Silicon

I'm going down to Home Depot soon, and I will pick up both size if I can find them. I also am ordering some Amazon ones as a backup - but that will keep the car down for another 2 days at least.

Finally, it's possible the local Jaguar dealer might have them in stock tomorrow.

Any feedback on these alternatives - and a part number for Jaguar - would be greatly appreciated, and perhaps useful to the other members of this forum.

Thanks in advance for everyone who responds - the members of this forum are really terrific, and have always come through - I hope to do the same in some small part.

James

 

It's 15/16" ID and 1 1/16 OD 1/8" thickness. I had to order off Amazon, but you might be able to find them somewhere. Most are metric, but I tried every metric size I could find and none would fit right.

 

Just checking we're talking about the same thing.


I bought this off Terry's Jag a while ago. I may still have the original octopus in a box somewhere and I can check the O ring sizes. I presume when you say the Norma Connection, you mean the white connector in my pic (not the green).

It's been a while, but I remember the of the new connectors didn't fit my 1999 Jag (maybe a PO changed the Jag connector to something generic, probably due to a leak, but the hose piping was definitely original ie gone rock hard). I had to get the connectors swapped out in a local Bahraini garage. No big deal.

Maybe you can buy those plastic boxes of assorted O ring sizes which allows you to pick and choose best fit. I did that on my engine PCV pipe breather when that broke. Hot engine bay/rubber/plastic never makes for lasting durable fittings and connections. I always change O rings as part of general maintenance when I fit/refit things. Not sure if the O ring material quality actually makes much difference but I guess Silicon will always last longer than plastic, but I've no experience on that.

 

Hi David,

Thanks for responding! On my car, the passenger side Norma connector has the green ring - that's the one I'm looking to replace.

I have ordered a box of o-rings that says it contains the suggested size(s), as well as a pack of silicone ones just in case.

I'm still interested to see if anyone else actually tried the silicone o-ring - like you said, I would expect that to far more resistant to heat ... but I wonder if the friction coefficient of that materiel against the metal tube that the Norma connector slides onto would be lower than rubber, and thus more likely to leak.

I'm still celebrating my luck that the connector came off easily and cleanly - I'm not sure I want to trust that that will happen again if whatever o-ring I put in there doesn't work ...

 

So - just to close the loop on this thread and hopefully my experience will be useful to other forum members.

This is the o-ring I installed into the passenger side Norma octopus hose connector. It fit perfectly, only took me 5-10 minutes to place inside the connector, and has been working perfectly for 2 months now:

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

I case that link disappears in the future, the description is this:

Dernord Silicone O-Ring,13/16" ID, 1-1/16" OD, 1/8" Width, 70A Durometer, Red (Pack of 10)

Someday in the future, when I'm feeling brave and ambitious, I intend to replace the driver's side o-ring on the octopus hose as well

I also tried this o-ring, which has superior temperature and elasticity specifications to any of the Buna or OEM rubber, but it was too thick to fit back over the hard pipe:

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

Description:

211 O-Ring, Viton, 75A Durometer, 13/16" ID, 1-1/16" OD, 1/8" Width, Black (Pack of 50)

I hope this helps!

(BTW - ultimately after replacing the o-ring and finding loose screw clamps on my new upper and thermostat hoses, I found that my lower radiator hose had been rubbing on the fan housing and worn a pinhole in it ... replaced that ... and the plastic front coolant crossover pipe ... and ultimately, the final culprit was the waterpump - even though it looked new!)

 

At least buy o rings made for automotive use thru Amazon or a local NAPA store, or a dedicated Jaguar vendor.

Home Depot & Lowes are handy mega hardware stores, but they carry items made for Home use , not high temperature automotive use. Even if they had an automotive section, I wouldn't trust their parts.

Z

 

After looking at the specs for temperature range, I came to the same conclusion

 

Reviving an old thread by Jimborino, as I recently spoke to a Classic Car restorer here in Bahrain about O ring quality and durability. He swears by HNBR (Hydrogenated Nitrile Butadiene Rubber) O rings used in the HVAC industry. He said that he fitted these to many of the American Muscle Cars he has maintained, over many years, and these Green O rings are as good as new when he's under the bonnet.

Checking on line data, they say (quote) ""HNBR is formulated to meet application temperatures ranging between -45 degrees C and 165 degrees C, and HNBR is classified by ASTM as DH-type polymer."

Just ordered a box online and let's see.