Spark plug bolts rusted/stripped
- Thread starter BigMike18
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firebirdguy
Member
just asking, but is the socket the right size & is fully seated on the plug? a true spark plug socket has a rubber insert to grab the plug & sometimes it takes some force to push it all the way on.
if it is on there right, the plug nut could be rounded letting the socket slip.
if it is on there right, the plug nut could be rounded letting the socket slip.
Attachments
Like MTN_man said, use penetrating oil (PB Blaster or Kroil). WD-40 does absolutely nothing on seized bolts. Then hammer on a 3/8" socket or maybe a 9mm if it's really rounded. If all else fails, you'll need to get a bolt extractor. Home Depot or Lowes usually has them in stock:
https://www.lowes.com/pd/IRWIN-BOLT-GRIP-5-Pack-Bolt-Extractor-Set/1000363541
https://www.lowes.com/pd/IRWIN-BOLT-GRIP-5-Pack-Bolt-Extractor-Set/1000363541
TechWrench
Senior Member
First of all, make sure all the surface rust is removed from the head of the bolt. If I remember correctly, that bolt is a 10mm metric. Be sure to use a 6 point socket (a 12 point might not grab if the bolt head has been reduced in size from surface rust). I would use a 3/8" drive socket with a breaker bar (instead of a ratchet wrench) and a 3" extension to control how you apply slow steady pressure when trying to break the bolt loose. If the 6 point 10mm socket still slips on the bolt head, then you have to go to a smaller size socket. I would next try a 3/8" (sae) 6 point socket. The 3/8ths sae socket is slightly smaller than the 10mm, and might work. If the 3/8ths socket fits, but not all the way on th bolt head, you can try lightly tapping the socket to seat it better on the bolt head. If the 3/8ths socket is still too large, then maybe try a 9mm next.
I would not use any heat (ie torch) on the bolt, you might ruin the coil the bolt is holding in place.
Another option, if you can get a 6 point socket that will fit snugly on the bolt head, is to use an old fashioned hammer driven impact driver (not an air gun). Many times the hammer impact along with the twisting action of the impact driver will break a stubborn bolt loose.
Remember you have a steel threaded bolt in a threaded hole in an aluminum head. There is bound to be some corrosion between the two types of metal.
I would not use any heat (ie torch) on the bolt, you might ruin the coil the bolt is holding in place.
Another option, if you can get a 6 point socket that will fit snugly on the bolt head, is to use an old fashioned hammer driven impact driver (not an air gun). Many times the hammer impact along with the twisting action of the impact driver will break a stubborn bolt loose.
Remember you have a steel threaded bolt in a threaded hole in an aluminum head. There is bound to be some corrosion between the two types of metal.
xtremewlr
Member
This. And use anti-seize when you finally put it back together.
AuSeeker
Elite Member
Also be careful not to break the bolt/s by applying to much force, those bolts are not all that big and will snap easily, then you'll be force to drill out the bolt(which is not easy drilling a steel bolt in aluminum without drifting off the broken bolt) and possibly have to drill and retap the hole to the next bigger size or install a Helicoil.
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That_Titanium_4RNR
New member
I think this goes without saying, but make sure you replace with new hardware when done. I had the same situation with mine when I did plugs. Had to hammer on a smaller socket
TechWrench
Senior Member
Yep, what I said.
NWTrailRunner
New member
If some of these bolt heads end up being too rounded, I can recommend the Topec bolt extractor set on Amazon. Pretty good range of sizes and they bite the bolt heads pretty well. But they only bite in the counter clockwise direction for removal, so won't help with rocking them back and forth like others have suggested.
