spark plug removal with engine slightly warm or cold
#1
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I'm getting ready to replace the spark plugs in my 991.1. The current plugs have only been in for about 20K miles, but need to replace based on time per Porsche guidelines. I've read a couple of nightmare stories about plug removal, and looking to minimize all risk.
Yes, I'm using the tools and procedures recommended by others on this forum, but I'm wondering if a slightly warm engine would be advantageous given the high thermal expansion coefficient of aluminum.
Anyone have any experience with this?
Thanks for any info.
Yes, I'm using the tools and procedures recommended by others on this forum, but I'm wondering if a slightly warm engine would be advantageous given the high thermal expansion coefficient of aluminum.
Anyone have any experience with this?
Thanks for any info.
#2
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I don't think you would have trouble either way.
When I was doing those major services on my previous 991.1 I would always warm up for the oil change and then prep as the oil is draining for the spark plug replacement as the engine cools.
Just remember things get really warm back there quicker then you think so don't cook you hands or arms around the cats.
When I was doing those major services on my previous 991.1 I would always warm up for the oil change and then prep as the oil is draining for the spark plug replacement as the engine cools.
Just remember things get really warm back there quicker then you think so don't cook you hands or arms around the cats.
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Sajan (11-06-2023)
#3
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the reason you're supposed to do plugs on a cold engine is because aluminum loses a lot of strength very quickly with temperature when compared to steel.
personally I've never had an issue hot or cold, but I'm also a Risk Taker(tm), so YMMV.
personally I've never had an issue hot or cold, but I'm also a Risk Taker(tm), so YMMV.
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Unless you plan to have two singed stumps where your hands used to be, I'd let it cool down completely.
Those exhausts and shields retain a lot of heat for a long time.
Those exhausts and shields retain a lot of heat for a long time.
#5
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As mentioned, you're supposed to do plugs on a cold engine otherwise the threads may come out with the plugs. I've done a few warm on Chevy V8s but I can remove a head in under an hour. I wouldn't think to do it on a 911... cost to fix is too high to wait a few hours or until the next day.
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#7
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I don't think you would have trouble either way.
When I was doing those major services on my previous 991.1 I would always warm up for the oil change and then prep as the oil is draining for the spark plug replacement as the engine cools.
Just remember things get really warm back there quicker then you think so don't cook you hands or arms around the cats.
When I was doing those major services on my previous 991.1 I would always warm up for the oil change and then prep as the oil is draining for the spark plug replacement as the engine cools.
Just remember things get really warm back there quicker then you think so don't cook you hands or arms around the cats.
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#8
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Always cold. Taking plugs out when hot can cause the threaded hole to contract too much as it cools.
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2022 Cayenne White
former 1972 911T white, 1984 911 3.2 Targa black, 993 cab white, 993TT arena red, 993TT silver, 996TT speed yellow, 991.1 GT3 white
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991.2 GT3 RS Weissach Racing Yellow
991.2 Turbo S GT Silver
991.2 GT3 Chalk (Manual)
2022 Cayenne White
former 1972 911T white, 1984 911 3.2 Targa black, 993 cab white, 993TT arena red, 993TT silver, 996TT speed yellow, 991.1 GT3 white
www.speedtechexhausts.com
info@speedtechexhausts.com
Testimonials SpeedTech Exhaust Videos facebook
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IXLR8 (11-08-2023)
#10
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Next time you visit the dealership take a glance at how many technicians (they're not mechanics) actually bother to use a torque wrench.
Things are usually tightened and then they simply give the thing an extra quarter turn.
Things are usually tightened and then they simply give the thing an extra quarter turn.
#11
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I see stuff like that and think "If they're willing to cut a corner on something as simple and easy as applying correct torque to a fastener or spark plug, what else are they willing to cut corners on?" Just one more reason why so many of us are glad to have the tools and ability to continue to do the majority of the regular maintenance on these cars ourselves. Not only will you save some real money in the long term, but chances are the job will get done better than it otherwise would have at a dealer.
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I used this. Worked great for my 991.2 spark plug job.
BELEY 14mm 3/8 inch Magnetic Swivel Drive 12 Point Spark Plug Wobble Socket Fits BMW, Thin Wall and Cr-V Steel (14mm) https://a.co/d/adDx1Eh
BELEY 14mm 3/8 inch Magnetic Swivel Drive 12 Point Spark Plug Wobble Socket Fits BMW, Thin Wall and Cr-V Steel (14mm) https://a.co/d/adDx1Eh
#15
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Scary, honestly.
I see stuff like that and think "If they're willing to cut a corner on something as simple and easy as applying correct torque to a fastener or spark plug, what else are they willing to cut corners on?" Just one more reason why so many of us are glad to have the tools and ability to continue to do the majority of the regular maintenance on these cars ourselves. Not only will you save some real money in the long term, but chances are the job will get done better than it otherwise would have at a dealer.
I see stuff like that and think "If they're willing to cut a corner on something as simple and easy as applying correct torque to a fastener or spark plug, what else are they willing to cut corners on?" Just one more reason why so many of us are glad to have the tools and ability to continue to do the majority of the regular maintenance on these cars ourselves. Not only will you save some real money in the long term, but chances are the job will get done better than it otherwise would have at a dealer.