Donate NOW and support Jag-lovers!

IMPORTANT! We have moved! The new site is at www.jag-lovers.com and the new Forums can be found at forums.jag-lovers.com

Please update your links. This old site will be left up for reference, until we can move all the old content over to the new site.

Volunteers wanted! Please help us move information from these pages to the new site, and also join us in providing new, exciting content.



Serving Enthusiasts since 1993
The Jag-lovers Web

Currently with 3,166 members





Spark Plugs and Ignition System Service

Spark Plugs and Ignition System Service

Doug Dwyer


Spark plugs are an easy do-it-yourself project on an XJ6 but can be a bit tricky on an XJ12. See the archives to learn about changing V12 spark plugs. Six cylinder spark plugs are easily accessible.

Most Jag owners prefer the orignal Champion spark plugs. Other types are acceptable and some owners like platinum plugs. There's hours of discussion in the archives about everyone's favorites.

For 6 cylinder cars use Champion N12YC (merchandising number 404). The NGK number is BP5ES (or GR4), and the Bosch number is WR8DC. Gap in all instances is .035". I am not sure what sparkplugs are correct for the V12 engines so I'll remain silent on the topic.

Change your sparkplugs on a cold motor and always use a dab of anti-seize compound on the threads.

Sparkplugs should last about 30,000 miles (48000 KM) under ideal conditions. Oil burning will decrease the life span as will a too-rich fuel mixture.

Inspect your plugs on removal...they should be light grey or tan. Black, fluffy plugs indicate a mixture problem (too rich) as do near-white plugs (too lean). Black, oily plugs indicate oil in the combustion chambers...from worn rings and such.

The distributor cap and rotor should also be changed every 30,000 miles or whenever the contacts show obvious corrosion or burning. Inspect them every 12,000 miles.

Spark plugs wires are a common mis-fire gremlin and they often fail intermittantly, making it difficult to pinpoint the fault. Plug wires ahould be replaced every 60,000 miles (96000 KM) on general principle, more often if inspection reveals burn spots from "leaks", cracking, or abrading. High under-bonnet temperatures take quite a toll on these wires. One way to check for "leakage" is to run the engine in a dark garage (don't asphyxiate !) and, if they are leaking, you'll see a real light show under the hood. Of course, this isn't the final word on spark plug wire testing but it can be fun.

Regularly check the primary igntion wiring to the coil and ballast resistor. This wiring, due to it's location, is very prone to heat deterioration and often frays and splits.


 

Please help support the move to the new site, and DONATE what you can.
A big Thank You to those who have donated already!

 


       
       
       
       

Go to our Homepage
Improve your Jag-lovers experience with the Mozilla FireFox Browser!

  View the latest posts from our Forums via an RSS Feed!

©Jag-loversTM Ltd / JagWEBTM 1993 - 2024
All rights reserved. Jag-lovers is supported by JagWEBTM
For Terms of Use and General Rules see our Disclaimer
Use of the Jag-lovers logo or trademark name on sites other than Jag-lovers itself in a manner implying endorsement of commercial activities whatsoever is prohibited. Sections of this Web Site may publish members and visitors comments, opinion and photographs/images - Jag-lovers Ltd does not assume or have any responsibility or any liability for members comments or opinions, nor does it claim ownership or copyright of any material that belongs to the original poster including images. The word 'Jaguar' and the leaping cat device, whether used separately or in combination, are registered trademarks and are the property of Jaguar Cars, England. Some images may also be © Jaguar Cars. Mirroring or downloading of this site or the publication of material or any extracts therefrom in original or altered form from these pages onto other sites (including reproduction by any other Jaguar enthusiast sites) without express permission violates Jag-lovers Ltd copyright and is prohibited
Go to our Homepage
Your Browser is: claudebot, IP Address logged as 44.222.122.246 on 29th Mar 2024 05:59:14