XJ-S Quality Control

A former Jaguar engineer spoke at a Rolls-Royce Owners Club event once. He stated that Jaguar was even more serious about leaks than RR and had a comprehensive leak test for every car coming off the assembly line and whenever they found one that didn’t leak, they’d send it back to make it right!!


Surely you meant system leaks. Definitely not water ingestion… That’s what takes place in the shadow of British history of automotive industry. Just do short research in Google, you will.see how many people lost their lives due to brake failures and fires… This is also the reason, why every insurance policy in UK covers fire as mandatory requirement. They were employing temporary workers like cashiers and delivery people, part-time. Those people were assembling your favourite piece of shaped sheet metal…

One thing I must admit. Production Engineers were brilliant and able to design manufacturing process for the workers without formal skills or technical education…

Ho ho. I am actually trying to shore up all my leaks! One year ago, i had two oil leaks, a transmission leak, and a power steering leak.

One year of using synthetic oil, my RMS leak seems to have stopped! I’ve since redone the transmission pan, as well as a power steering hose. I am down to just an oil pan leak, which I will be addressing soon.

If I get my XJS V12 leak free, do I get a prize?

I think a prize is in order. Don’t hold your breath, though- I check the mailbox every day. So far- nuthin.

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No, you will get rust - having disabled the Jaguar automatic rust proofing system.


Somehow that anti rust system doesn’t seem to work very well in the US Northeast or the UK.

Stop throwing salt on the roads in winter!

Better yet, don’t pull the cat out in the winter

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This is due to different oil viscosity used between the geographic locations. Also - somehow Jaguar’s RP system is deemed unacceptable in UK so every owner needs to power-wash it 30minutes prior to MOT. Only in that short time window - rust can progress 0.2mm into metal structure… That makes 5 MOTs prior to welding repairs.

Now seriously and without bull. Speaking of quality control - can you recognise the sticker and part below?

Any suspicious things noted?

That the sticker is dirty?


That sticker is due to “critcal characteristic” and should be placed on bare metal tank prior to
degreasing / painting. Naturally - taken off shortly before entering spray chamber. Such a small detail in Jaguar’s standard operating procedure :wink:

Believe it or not - I have found paint bubbles on the tank - assuming that these are corroded pin holes. After scratching it open - I have found 27 years old water drops under it. I must admit it was well painted-over - rust pitting was minimal…