LS1 Spark Plug Help
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
LS1 Spark Plug Help
Hello All:
First, let me say thank for you allowing me in the forum. Took ownership of my first Vette a few days ago (99 Coupe, 6-Speed Manual) and I already find this site a great help.
My question is about plugs. Due to multiple owners prior to me, I don't know how long the plugs have been in and I'd like to change them. Also, I have know idea if the guy before did it right (i.e., anti-seize). In trying to free the first plug, I found it to be quite tight...so I stopped. I feared breaking it or backing out the threads if I went with too much torque to the ratchet handle. . Right now I am hitting the plugs with PB Blaster and letting them sit before trying again. I tried while engine was cold.
Any advice on removing plugs from these heads if they are somewhat stuck.
Thanks!
First, let me say thank for you allowing me in the forum. Took ownership of my first Vette a few days ago (99 Coupe, 6-Speed Manual) and I already find this site a great help.
My question is about plugs. Due to multiple owners prior to me, I don't know how long the plugs have been in and I'd like to change them. Also, I have know idea if the guy before did it right (i.e., anti-seize). In trying to free the first plug, I found it to be quite tight...so I stopped. I feared breaking it or backing out the threads if I went with too much torque to the ratchet handle. . Right now I am hitting the plugs with PB Blaster and letting them sit before trying again. I tried while engine was cold.
Any advice on removing plugs from these heads if they are somewhat stuck.
Thanks!
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,439
Likes: 2,183
From: Buffalo Texas
First Congrats and welcome (I also have a 99 six speed coupe) the engine needs to be cold, I have no idea what is tight to you but sometimes they can be very difficult and it is better to stop and think about it as you have done !!!! Letting them soak is not bad, I just don't know if it can get where it will do some good ??? Try going back and forth even if you don't think they are moving ??? Worse case you break them and pull the heads and put some better ones on with a new cam and headers ???? LOL
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
How much is too much.....
First Congrats and welcome (I also have a 99 six speed coupe) the engine needs to be cold, I have no idea what is tight to you but sometimes they can be very difficult and it is better to stop and think about it as you have done !!!! Letting them soak is not bad, I just don't know if it can get where it will do some good ??? Try going back and forth even if you don't think they are moving ??? Worse case you break them and pull the heads and put some better ones on with a new cam and headers ???? LOL
Thanks AKA....I know. It is hard to judge how much force is too much. I only used the standard size ratchet handle. I was afraid the breaker bar would be too much force. Ugh....maybe I should save the plug change until the winter season when she can sit in my garage for few months and I can drive her anyway (New England....)
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
Also............
I read in another thread somewhere with respect to the potential for breaking plugs or stripping threads that "it almost never happens"...therefore use the force. I am skeptical. Thoughts appreciated.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I doubt PB Blaster will be able to soak in because the plug base seals against the head.
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
Thanks.....
I doubt PB Blaster will be able to soak in because the plug base seals against the head.
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Hello Bill, thanks for the advice. I already purchased plugs, but I bought Denso iridium plugs.... Re: the wires, they appear to be in decent shape, but I have some on order from Jegs (MSD wires). The coils appear to be stock GM coils which I hear good things about.
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
I doubt PB Blaster will be able to soak in because the plug base seals against the head.
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Just MAKE SURE that you are actually turning the plug to the LEFT!
Like AKA recommended, turn left and then a little right. Once you break the head to plug seal, it should come out pretty easy.
I would not be afraid to use a little longer ratchet or breaker bar. There either going to break loose and come out easy or there going to rip the threads out.
If you are really worried and afraid that there STUCK, you can get a torch and warm up the area AROUND the plug to about 150 deg (NOT THE PLUG) and see if that helps.
WIRES. If you are not sure of the spark wire condition or if you damaged them, I highly recommend the GM RED Performance wires as a replacement wire.
Replace the plugs with GM AC Delco Iridium plugs.
Use a little bit of silver antiseize on the new plug threads and use DIELECTRIC GREASE inside the plug boots.
Bill C
Bill, I was thinking over your advice re: the torch to heat the area to 150 degrees.....any reason why running the engine briefly to get some heat in the motor wouldn't accomplish the same? Thanks.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
YES!!! When you run the engine you heat up the PLUG AND the HEAD. If you have a STUCK Plug and heat the head around the plug, the aluminum around the plug will expand a very slight amount and have less grip on the plug threads.
BC
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Racer
Joined: Feb 2012
Posts: 382
Likes: 53
I just changed plugs on my car. It all started when I went to CHECK a plug and the thing was in so tight it snapped in half when I tried to remove it. I snapped a total of 3 off at the insulator base. Mind you I was using a spark plug socket too. It wasn't a huge issue since the socket could still get around the plug and get the bottom part out. Torque on the plugs is only supposed to be 11 ft lb and yes use anti seize putting the new ones in and die electric grease on the boots. Unfortunately a gorilla was the previous owner of my car.
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
I just changed plugs on my car. It all started when I went to CHECK a plug and the thing was in so tight it snapped in half when I tried to remove it. I snapped a total of 3 off at the insulator base. Mind you I was using a spark plug socket too. It wasn't a huge issue since the socket could still get around the plug and get the bottom part out. Torque on the plugs is only supposed to be 11 ft lb and yes use anti seize putting the new ones in and die electric grease on the boots. Unfortunately a gorilla was the previous owner of my car.
Burning Brakes
Joined: May 2013
Posts: 1,249
Likes: 142
From: Lynn MA
Hello, and where are you in N.E. ? You can put that in your profile so we know where your from. As others have mentioned you may need to use more arm strong than you'd like. I changed my plugs and wires at 121,000 miles and they must have been original.
For one the wires wouldn't even come off. I destroyed or cut 5 of them to get them out of the way. Then the plugs were in so tight I had to take a bunch of steroids to get up the strength to break them loose. Finally got them out after two hours but everything went in fine and the car purred like a kitten since. Anti-sieze is your friend.
Tom
For one the wires wouldn't even come off. I destroyed or cut 5 of them to get them out of the way. Then the plugs were in so tight I had to take a bunch of steroids to get up the strength to break them loose. Finally got them out after two hours but everything went in fine and the car purred like a kitten since. Anti-sieze is your friend.
Tom
Safety Car
Joined: Mar 2015
Posts: 3,637
Likes: 245
Hello All:
First, let me say thank for you allowing me in the forum. Took ownership of my first Vette a few days ago (99 Coupe, 6-Speed Manual) and I already find this site a great help.
My question is about plugs. Due to multiple owners prior to me, I don't know how long the plugs have been in and I'd like to change them. Also, I have know idea if the guy before did it right (i.e., anti-seize). In trying to free the first plug, I found it to be quite tight...so I stopped. I feared breaking it or backing out the threads if I went with too much torque to the ratchet handle. . Right now I am hitting the plugs with PB Blaster and letting them sit before trying again. I tried while engine was cold.
Any advice on removing plugs from these heads if they are somewhat stuck.
Thanks!
First, let me say thank for you allowing me in the forum. Took ownership of my first Vette a few days ago (99 Coupe, 6-Speed Manual) and I already find this site a great help.
My question is about plugs. Due to multiple owners prior to me, I don't know how long the plugs have been in and I'd like to change them. Also, I have know idea if the guy before did it right (i.e., anti-seize). In trying to free the first plug, I found it to be quite tight...so I stopped. I feared breaking it or backing out the threads if I went with too much torque to the ratchet handle. . Right now I am hitting the plugs with PB Blaster and letting them sit before trying again. I tried while engine was cold.
Any advice on removing plugs from these heads if they are somewhat stuck.
Thanks!
Racer
Joined: Feb 2012
Posts: 382
Likes: 53
Thread Starter
Heel & Toe
Joined: Apr 2016
Posts: 21
Likes: 1
From: Northbridge Massachusetts
First Congrats and welcome (I also have a 99 six speed coupe) the engine needs to be cold, I have no idea what is tight to you but sometimes they can be very difficult and it is better to stop and think about it as you have done !!!! Letting them soak is not bad, I just don't know if it can get where it will do some good ??? Try going back and forth even if you don't think they are moving ??? Worse case you break them and pull the heads and put some better ones on with a new cam and headers ???? LOL
Just a quick followup AKA...I finally got around to doing this and your advice helped. A slightly bigger bar and easy rock tight and loose and they popped right out! I think it was mainly fear holding me back....fear of breaking one off!
1/4 mile/AutoX
Joined: Jun 2014
Posts: 11,439
Likes: 2,183
From: Buffalo Texas
hope you Anti-Seized the new ones ???
