How to install spark plug ?

[hobieboy]

Wayne's book said the set the gap of the plug before installing it.

I'm putting in new plugs. Do I need to do anything prior to installing it? How do I find out what gap I need to set it to? And how to do that?

Thanks...

[masraum]

Here's a good link
http://www.ehow.com/ehow/ehowDetails.jsp?index=1105&id=110

The gap should be in a service manual, the owner's manual, or possibly even on a sticker somewhere near the engine. Someone from the board may even post it for you. What sort of plugs are you going to use, certain plugs require a little more care than others when gapping (like Bosche platinum) because instead of a large metal center electrode they have a thin wire in the center of a porcelain insulator and the platinum wire can easily be damaged.

[hobieboy]

I am using the factory recommended Bosch W3DPO so sounds like I have the fragile plugs then

[Superman]

You know, I think the copper plugs will still work better in your car than the platinum ones. In water cooled cars, in a fairly narrow but high temperature range, platinum has nice self-cleaning properties. But in our cars, copper actually works better. YMMV.

Gapping tools are cheap cheap cheap, on the counter of your favorite auto parts store. If you install plugs without one, just look carefully at all six. They are gapped at the factory, so really you're just looking to see if one has been damaged, or is different from the others. If they all look the same, install them.

And finally, the torque spec for spark plugs is about 18 lb/ft. That's the force it takes to crush the crush-washer at the base of the plug. When you feel that washer get crushed, you're done. Do not overtighten. The factory toolkit spark plug tool works best.

[hobieboy]

Thank you guys... will run out to get the tool tonight.

Superman,

I have heard the same suggestion as well - platinum is good for water cooled cars but not air cooled. But my limited research didn't return any useful alternative so I thought I'll bite the bullet this time & go with the expensive ones again.

Are you running with copper plugs but at the same temp range as factory recommended?

[kqw]

are you planning to use anti-sieze?????????

[hobieboy]

no - per Wayne's book & factory recommendation

[Superman]

Yes, I run copper plugs, but mine is not a 930. Your mileage may vary. Anti-sieze or no, just don't overtorque, or undertorque, spark plugs. The heads they screw into are aluminum. The proper torque spec is achieved just when the crush washer is finished crushing.

[ChrisBennet]

I think the expensive Bosch platinum plugs for the Turbo's are a different (better) animal than the $2 platinums use on 911's.
-Chris

[tsuter]

Sometimes I have to use two "crushies' to get the plugs indexed just right.

Does the "book" cover indexing??

[gerry100]

Don't forget to get the "boot" down onto the #6 plug ( rigth side, front). Its a pain, but if you don't water etc gets down in there and can corrode the connector.

[911pcars]

"Sometimes I have to use two "crushies' to get the plugs indexed just right. "

Using two spark plug gaskets may inhibit heat transfer from the plug to the cylinder head and thus change the heat range.

Don't the indexing kits include thicker spacers to position the plug electrodes?

Sherwood

[Eric Coffey]

Also, when gapping them, DO NOT do so by leaving the feeler gauge in and tapping it to the right height. You will damage the electrode.

[VaSteve]

Originally posted by Eric Coffey
Also, when gapping them, DO NOT do so by leaving the feeler gauge in and tapping it to the right height. You will damage the electrode.

I used to do it that way. Have not done the 911 yet. What is the proper procedure??

[no substitute]

There is bending/gap check tool available from Bosch.

[GSpreeman]

Good God. It's time to change my plugs. I opened the hood and it looks like a nightmare to get at the plugs. I see why you guys pull the A/C...I could use the extra room right now. Any other tips on getting to these things?

[Por_sha911]

I know that it is possible to do all the plugs without moving the AC (did it several times). The pipe on the left side is a no-brainer.
Biggest tip: get the factory tool!!! It works great and you won't drop a plug or extension.
Second biggest tip: go easy on putting in the new plugs because a cross-threaded plug is a nightmare. If you feel resistance, pull out the plug and start over.

[tsuter]

Originally posted by 911pcars
"Sometimes I have to use two "crushies' to get the plugs indexed just right. "

Using two spark plug gaskets may inhibit heat transfer from the plug to the cylinder head and thus change the heat range.

Don't the indexing kits include thicker spacers to position the plug electrodes?

Sherwood

I never heard of that!!! Indexing washer vs. squishy - a material heat transfer difference?? Is that just your personal theory or do you have some test data to back that up??

Guys have been using extra squishies for years if washers aren't available!!!

[911pcars]

No test data, just something I read.

Do you have any data showing there is no difference other than some folks have been doing this for years?

I also used the term, "may inhibit heat transfer..." so as not to appear to be an expert in this matter.

In fact, the power increase from indexing spark plugs may be negligible in most engines and very minor in others. There I go, using that "may" word again.

Sherwood

[tsuter]

Too many "opinions" and "theory" on this board. Most it it hyping non existent or theoretical problems with no practical experience or data to support it
I have never seen a problem or difference from using two type of washers. Unless your plugs are beveled!!! LOL!!!

If you have seen a problem - state it and when and how and document it.

Otherwise be clear that this is just your opinion and you have no facts to back it up.