what is with the first spark plug?
- Thread starter hoosays
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Chongo
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galled threads
what is with the first spark plug?
Went to change the spark plugs in my 2001 Discovery II, and the first one nearest the air filter just will not thread more than halfway. I've been with it for 2 hours and every angle i try, no good. Any clues?
Hello Hoosays, The heads are made out of aluminum and the threads of the sparkplugs are made of stainless and different various alloys.
When removing the old plug, sometimes the carbon buildup is sufficient to gall a portion of the threads while removing the plug that was installed dry. Also when installing new plugs, never force them with hand tools, use only your fingers to snug them up then then torque to spec.
It sounds like to me that the threads are cross threaded or galled. What I would recommend is to get a spark plug thread chaser from a parts store that is near by, and re chase the threads, of what is left. A helicoil aka ( plug saver ) " Timesert " may be necessary if the damage to the threads is too severe. I don't endorse helicoil for this application but here is their website.
http://www.emhart.com/products/helicoil.asp?gclid=CLT2sPeAsZMCFSUaagodWEfpoA
I like timeserts myself for bad plug threads in cylinder heads, and strongly endorse them as the easiest and best repair. Simply put, I've had the best expiriance with timesert. but they're not cheap, that's why I also put in Helicoil. But beware of helicoil plug repairs, it allows combustion chamber gases to seep around the helicoil and make a mess of things. Timesert is the best bet in this situation where you want to seal the combustion chamber.
http://www.timesert.com/
Always use never seize or anti seize on the threads to make installation and extraction easier, never install plug threads dry.
Plugs should never be installed into any engine without a gilding metallic graphite type lubricant on the plug threads i.e. anti seize or never seize.
http://www.autoaccessconnect.com/anselu.html
Plugs don't have to be that tight, the book calls for 15 foot pounds, but I use 5 - 10 FT LBS.
Good luck, keep the threads lubed with anti seize or never seize
Chongo
what is with the first spark plug?
Went to change the spark plugs in my 2001 Discovery II, and the first one nearest the air filter just will not thread more than halfway. I've been with it for 2 hours and every angle i try, no good. Any clues?
Hello Hoosays, The heads are made out of aluminum and the threads of the sparkplugs are made of stainless and different various alloys.
When removing the old plug, sometimes the carbon buildup is sufficient to gall a portion of the threads while removing the plug that was installed dry. Also when installing new plugs, never force them with hand tools, use only your fingers to snug them up then then torque to spec.
It sounds like to me that the threads are cross threaded or galled. What I would recommend is to get a spark plug thread chaser from a parts store that is near by, and re chase the threads, of what is left. A helicoil aka ( plug saver ) " Timesert " may be necessary if the damage to the threads is too severe. I don't endorse helicoil for this application but here is their website.
http://www.emhart.com/products/helicoil.asp?gclid=CLT2sPeAsZMCFSUaagodWEfpoA
I like timeserts myself for bad plug threads in cylinder heads, and strongly endorse them as the easiest and best repair. Simply put, I've had the best expiriance with timesert. but they're not cheap, that's why I also put in Helicoil. But beware of helicoil plug repairs, it allows combustion chamber gases to seep around the helicoil and make a mess of things. Timesert is the best bet in this situation where you want to seal the combustion chamber.
http://www.timesert.com/
Always use never seize or anti seize on the threads to make installation and extraction easier, never install plug threads dry.
Plugs should never be installed into any engine without a gilding metallic graphite type lubricant on the plug threads i.e. anti seize or never seize.
http://www.autoaccessconnect.com/anselu.html
Plugs don't have to be that tight, the book calls for 15 foot pounds, but I use 5 - 10 FT LBS.
Good luck, keep the threads lubed with anti seize or never seize
Chongo
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