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Jehu
05-23-2007, 08:31 AM
I bought Bosch coppers and a set a of valve cover gaskets expecting to change my plugs. Do these plugs require setting the gap and should I also buy new valve cover bolt washers or do these rarely show up bad? Also is it a must to use a Torque wrench and apply a certain force when tightening the new plugs or should a half a turn from snug or so be sufficient.

Tiger
05-23-2007, 08:42 AM
Plugs are already gapped... Tightening is usual 1/4 turn from snug or so.

Torque wrench on the valve cover gasket... yes. The small 3/8" torque wrench. Never the 1/2" one.

Alexlind123
05-23-2007, 08:58 AM
Yea, the valve cover torques are really touchy. You will want to use a good quality 3/8'' whrench and be careful. A little too tight or loose can easily case a leak. As for the plugs, im not a master mechanic, but i used a torque wrench with a spark plug socket just to be safe.

Jehu
05-23-2007, 09:09 AM
Thanks , what about the cover bolt washer/grommets? Smart to buy a set just to be safe I'd imagine weather any are decayed or i lose one. Would it be unwise to do this outdoors? I understand you should only do the plugs on an Aluminum block when its cool so ideally I'd like to do this where its parked but i'm under trees and there's pollen and all kinds of crap floating around I'd be concerned I'd miss something falling in there and end up with a problem.

Ross
05-23-2007, 09:14 AM
Cool motor and anti- sieze on the threads.

BigKriss
05-23-2007, 09:15 AM
you really used a torque wrench on the spark plugs. I just put some anti-seize past on the plugs and forget about them. I mean how hard can you really put them in untill you know they are tight. Same with the valve cover nuts, i never used a torque wrench on them, then again I only have a 1/2" driver version.


Yea, the valve cover torques are really touchy. You will want to use a good quality 3/8'' whrench and be careful. A little too tight or loose can easily case a leak. As for the plugs, im not a master mechanic, but i used a torque wrench with a spark plug socket just to be safe.

Jehu
05-23-2007, 09:30 AM
I read the plugs all come with an anti sieze compound on the threads anyway. How about the Valve Cover gaskets? Do they require any kind of cement or anything or just slip them on and bolt them down?

BigKriss
05-23-2007, 09:39 AM
I've never bought spark plugs with antiseize paste on them and you might want to use some hyolmar to ensure the gasket sticks to the cylinder head.


I read the plugs all come with an anti sieze compound on the threads anyway. How about the Valve Cover gaskets? Do they require any kind of cement or anything or just slip them on and bolt them down?

Jehu
05-23-2007, 09:43 AM
from http://nightrider.com/biketech/spkplghnbook.htm#tips
Installation Tips
Here are a couple of tips to help assure the success of changing spark plugs. The first is to remove spark plugs from aluminum cylinder heads only when the engine is cool. Since aluminum and steel expand and contract at different rates, removing spark plugs from an aluminum cylinder head while hot can actually cause thread and cylinder head damage. Before installing the spark plugs, make sure the threads are clean and in good condition. If in doubt, run a thread chaser through the plug opening in the cylinder head. Most plug manufacturers recommend that you do not use an anti-seize compound, since one has already been applied to the plugs at the factory. Next, install the spark plugs finger tight and, it using a taper seat spark plug, use a ratchet to rotate 1/16 of a turn. If using a gasket seat type spark plug, after installing finger tight, turn 1/4 to 5/8 of a turn. If this procedure is followed, spark plugs will not back out nor will they seize in the cylinder head.

BigKriss
05-23-2007, 09:52 AM
I've never heard of someone running a thread chaser were the plugs go, I guess someone could do it, it would just take a while and I've never bought plugs with anti-sieze paste on them. NGK makes no mention of not using anti-sieze paste. http://www.ngkspark.com.au/tech_index.htm?http://www.ngkspark.com.au/pages/tech_content.htm

They are the plugs I'm running.


from http://nightrider.com/biketech/spkplghnbook.htm#tips
Installation Tips
Here are a couple of tips to help assure the success of changing spark plugs. The first is to remove spark plugs from aluminum cylinder heads only when the engine is cool. Since aluminum and steel expand and contract at different rates, removing spark plugs from an aluminum cylinder head while hot can actually cause thread and cylinder head damage. Before installing the spark plugs, make sure the threads are clean and in good condition. If in doubt, run a thread chaser through the plug opening in the cylinder head. Most plug manufacturers recommend that you do not use an anti-seize compound, since one has already been applied to the plugs at the factory. Next, install the spark plugs finger tight and, it using a taper seat spark plug, use a ratchet to rotate 1/16 of a turn. If using a gasket seat type spark plug, after installing finger tight, turn 1/4 to 5/8 of a turn. If this procedure is followed, spark plugs will not back out nor will they seize in the cylinder head.

Bill R.
05-23-2007, 10:08 AM
No spark plug manufacturers recommend antiseize on any spark plug anymore. Many of them state specifically not to use it. Here's one example from Delco
(http://web.archive.org/web/20010609133633/http://www.acdelco.com/parts/tech/1530n.htm)



I've never heard of someone running a thread chaser were the plugs go, I guess someone could do it, it would just take a while and I've never bought plugs with anti-sieze paste on them. NGK makes no mention of not using anti-sieze paste. http://www.ngkspark.com.au/tech_index.htm?http://www.ngkspark.com.au/pages/tech_content.htm

They are the plugs I'm running.

BigKriss
05-23-2007, 10:11 AM
well you have proved me wrong again Bill. I aways did it in the past.


No spark plug manufacturers recommend antiseize on any spark plug anymore. Many of them state specifically not to use it. Here's one example from Delco
(http://web.archive.org/web/20010609133633/http://www.acdelco.com/parts/tech/1530n.htm)

Ross
05-23-2007, 10:17 AM
They can kiss my ass. I haven't overtightened one yet but I have struggled like crazy tyring to remove plugs from aluminum heads that had seized from electrolysis.
Some say it inhibits heat transfer also, again I've never had a problem.
What do you do Bill? Where have you been?

Bill R.
05-23-2007, 10:45 AM
spark plugs anymore at all. 25 years ago it was a problem with porsches and vw's motors where you would seize plugs that would rip out all the threads on the way out. I personally haven't had a seized plug damage threads in over 15 years now. Virtually all spark plug threads are nickel plated now to resist corrosion, galling and electrolysis. There are numerous articles regarding the use of antiseize on any fasteners and they usually have charts to indicate how much you have to lower the torque since the antiseize functions as a good lubricant and if you torque to the same spec you will put a much greater load on the threads. Typical reductions are something like 25% less torque to avoid overtightening.
I've also read the same things as you Ross regarding poor heat transfer from the plug when using antiseize and altered dielectric properties. I don't know how much fact is there. I do know that on the newer ford 4.6 motors many people are pulling the threads out of the heads when installing spark plugs. I attribute this to 3 things. First a poor design by ford with insufficient threads and secondly ,people using antiseize and overtorquing them unintentionally. Or third gorillas just overtorquing period.





They can kiss my ass. I haven't overtightened one yet but I have struggled like crazy tyring to remove plugs from aluminum heads that had seized from electrolysis.
Some say it inhibits heat transfer also, again I've never had a problem.
What do you do Bill? Where have you been?

Mr._Graybeard
05-23-2007, 10:51 AM
As for the grommets, by all means replace them. Chances are, many of them will crumble when you try to remove them anyway.

On my car I suspect they were the actual cause of valve cover leakage rather than the gaskets themselves. If I had it to do all over, I would have tried just replacing the grommets before going to the hassle of pulling the valve covers.

Jehu
05-23-2007, 05:10 PM
Thanks for the help.

bigtisas
05-23-2007, 08:39 PM
I never use torque wrench on my cars. Just hand tight as much as you can with the socket and then use the wrench to do another half turn.

Chris'91'525i
05-23-2007, 09:22 PM
spark plugs anymore at all. 25 years ago it was a problem with porsches and vw's motors where you would seize plugs that would rip out all the threads on the way out. I personally haven't had a seized plug damage threads in over 15 years now. Virtually all spark plug threads are nickel plated now to resist corrosion, galling and electrolysis. There are numerous articles regarding the use of antiseize on any fasteners and they usually have charts to indicate how much you have to lower the torque since the antiseize functions as a good lubricant and if you torque to the same spec you will put a much greater load on the threads. Typical reductions are something like 25% less torque to avoid overtightening.
I've also read the same things as you Ross regarding poor heat transfer from the plug when using antiseize and altered dielectric properties. I don't know how much fact is there. I do know that on the newer ford 4.6 motors many people are pulling the threads out of the heads when installing spark plugs. I attribute this to 3 things. First a poor design by ford with insufficient threads and secondly ,people using antiseize and overtorquing them unintentionally. Or third gorillas just overtorquing period.

Yes IMO, I agree 100% with Bill's post. (but who the hell am I :D )
Why people would put a nickel anti-seize paste on a nickel plated plug always amused me.
Some claim copper is better due to higher melt point.
On an exhaust system it might be slightly better, but for spark plugs it's not necessary if it has a nickel finish from the factory.
A black oxide plated plug like on an Autolite might benefit from a very light coating of nickel paste.

Jehu
05-23-2007, 09:26 PM
should i use any gunk on the valve cover gaskets as Kris suggested? I've heard they can be a pain to get to stay on as you try and fit the covers back on thanks to Gravity.

Shankster
05-23-2007, 09:40 PM
New grommets please. You'll most likely find that the old ones are toast.

High quality 3/8 in-lbs torque wrench. Tighten in criss-cross pattern in stages until you hit 90 in-lbs. Took a few passes.

Use a couple of clean trash bags over the side you're working on if you're worried about stuff getting in the motor.




Thanks , what about the cover bolt washer/grommets? Smart to buy a set just to be safe I'd imagine weather any are decayed or i lose one. Would it be unwise to do this outdoors? I understand you should only do the plugs on an Aluminum block when its cool so ideally I'd like to do this where its parked but i'm under trees and there's pollen and all kinds of crap floating around I'd be concerned I'd miss something falling in there and end up with a problem.

Shankster
05-23-2007, 09:44 PM
I read the plugs all come with an anti sieze compound on the threads anyway. How about the Valve Cover gaskets? Do they require any kind of cement or anything or just slip them on and bolt them down?

Thin bead of O2 sensor safe sealant on the half moon sections and towards the front of the motor where the joint is (the 90 degree turns). You'll see the mating surface when you take the vc off.

I used a thin film of motor oil on the part of the gasket which fits into the cover. I think the official reco is to use glycerin. No idea where to find it.

Jehu
05-23-2007, 09:49 PM
Thin bead of O2 sensor safe sealant on the half moon sections and towards the front of the motor where the joint is (the 90 degree turns). You'll see the mating surface when you take the vc off.

I used a thin film of motor oil on the part of the gasket which fits into the cover. I think the official reco is to use glycerin. No idea where to find it.

Eeeeeggggcellent! Great suggestions. I can see my way clear now.Thanks a million.

stargazer_61
05-24-2007, 08:48 AM
Like everyone else says, torque correctly center to outside & use new grommets. You can bang them out with a deep socket, 7 or 8 mm, I can't remember what I used.

Also make sure that the gasket surface and grove on the VC is clean and smooth. Mine were very crusty. I was having mine bead blasted and powder coated so I didn't worry about that once I saw how nasty they were.

Jehu
05-24-2007, 12:08 PM
Something just occurred to me and i guess i was ambiguous about this job. I did mention valve covers because i thought i had to remove them to change the spark plugs.. I just realized i do not need to remove the entire valve cover and i believe the seller just over a year ago replaced the valve cover gaskets so i guess i have a set of new gaskets if anyone wants to buy them,lol.. I would return them but the plastic covering on the package ripped so i doubt they'd accept them back.

E34 530
05-24-2007, 02:46 PM
Something just occurred to me and i guess i was ambiguous about this job. I did mention valve covers because i thought i had to remove them to change the spark plugs.. I just realized i do not need to remove the entire valve cover and i believe the seller just over a year ago replaced the valve cover gaskets so i guess i have a set of new gaskets if anyone wants to buy them,lol.. I would return them but the plastic covering on the package ripped so i doubt they'd accept them back.

lol, I was so confused reading your post thinking "why is he going to remove the entire valve cover to change spark plugs," but just shrugged it off. But now your post confirms it. :p

Jehu
05-24-2007, 09:32 PM
I think i got the idea reading archived posts which included other models .

632 Regal
05-25-2007, 01:48 AM
I over read this thread also, I thought he wanted to replace the plugs as he replaced the VC gaskets...hmpff

I too initially believed to use antiseize untill Bill mentioned not to and pointed me to a link. I dont need to be stripping stuff out. If the bolt/sparkplug dont have a zink coating use antiseize if its coated its good to go as is. This would apply to any bolts going into aluminum.

Another great point mentioned in this thread is NEVER EVER remove plugs/bolts on a hot engine, it WILL remove the threads in the aluminum with the bolt.


I think i got the idea reading archived posts which included other models .