"How to" change plugs, wires, cap, rotor?

[oregonmon]

Hey all,
I am trying to resolve a miss or rough running SC under load and am going to change plugs, wires, cap and rotor. All Bosch OEM products. As I have never does this job and need a lot of help, does anyone have a link to a good how to or feel like giving me one here. I did see there is a tech article on Pelican for Magnecor, I imagine it would be the same. This surely has been covered numerous times right?
Hope the spring is treating you and your driving addiction well.

[old man neri]

Well my tips are:

1) Get a bently manual and/or 101 projects for your 911
2) Use the factory spark plug tool
3) Change your wires one at a time so you don't cross anything
4) Take your time with the plugs and don't force anything, cross threading a plug is a nightmare

-matt

[glewis80SC]

Bentley manual for sure!!! Be patient when doing the plugs, they can be a pain getting in and out.

[rusnak]

Yes I agree with the first two posters.

I noticed that Amazon has the manual. One of the alternatives that I like (forgot who's tip this is, so sorry) is to thread the spark plug with a rubber fuel hose. That idea sounds good, but I haven't tried it. Whatever you do, don't try to change them while the engine is hot.

Did you check your timing advance too?

[Superman]

The distributor cap has a "key". That is, it only fits onto the distributor body one way. There is a notch in the rim of the distributor body that engages with the "key" in the rim of the cap. Other than this, and the advice of using the factory spark plug tool, should be enough for you. Take your time. If you stay focused, it is what we call a "one beer" job.

[dshepp806]

Be sure to get a good seat on the plug wires.

I guess most install the plugs dry (I think the book states this). I've taken to some advice I rx'd from Pete Zimmerman, making very, very light use of L grease on my threads.

You want to ensure proper torque on the plugs, as well....22 foot pounds.

Spark plug gap, of your choosing based on spark plug selection.

What Superman said,..if not positioned properly, you stand a chance of cracking the distributor when you latch it down.....(something I did way, way back).

Have a nice magnet nearby, just in case you drop a plug into netherland.

Take LOTSA time, ensuring not to crossthread the plug (what glewis80SC said)

Take special care to route the wires nicely,...no rubbing/touching where it shouldn't.

Make sure the rubber cover (?) at the spark plug end of ignition wires is seated down nicely.

These points applicable to my 89.

Best of luck,

[Superman]

When the crush washer at the base of a spark plug finishes crushing (you dan feel it crush, and then you can feel it get tight once it has crushed completely), then you are at the correct torque. Spark plugs are commonly over-torqued. With aluminum heads, over-torquing spark plugs is.........a mistake.

[HarryD]

Ryan,

This is not much harder than changing your oil. The above advice is very good.

Tools
-Factory Spark plug wrench
-Dielectric Grease
-Marker

Procedure
1-Remove cap by unhooking the two clips that are 180 degress apart. Mark the wire closest to the fan housing (more on this later). Lift cap off.

2-Note position of rotor and pull rotor out by pulling straight up.

3-You will see a hole under the shaft that the rotor is on and a felt plug. Use a pick (something like what a dentist uses to clean your teeth-you wife may be able to get you a nice sharp one from work) to remove the plug and put a few drops of motor oil into the hole. Replace plug.

4-Put new rotor onto shaft. It is keyed and can only go on one way. Remeber how the old one was oriented. Be sure it is fully seated.

5-Take new cap and place over rotor. It is also keyed and can only go on one way.

6-Remove the wire that you marked in the first step from the old cap. Find the other end and remove it from the spark plug.

7-Use the factory tool to remove the old spark plug.

8-Install the new spark plug. Start by hand. It should go in pretty easy for a few turns (be sure it is not crossthreaded). Once started, turn until you feel the spark plug seat and give it a firm turn until you can feel the washer begin to give (seat). You do not need to be a gorilla.

9-Find the new wire that matches you old wire in length. Smear a dab of dielectric grease in the inside of each boot. Route the wire like the old wire was routed.

10-Attach the wire to the sprk plug. Press until you feel a slight click.

11-Attach the other end of the wire to the distributor post that corresponds to the old wire you took the old one off of. (If this is the first one, it is the one closest to the fan housing). You may need to "burp" the air out of the boot to get it fully seated.

12-Repeat steps 6 to 11 until all six wires are replaced.

13-Replace the wire from the Coil to the center of the Distributor.

You are done!

[DRACO A5OG]

If I may add,

Engine must be cold.

If you have an AC, you need to remove the AC Compressor to gain easier access to the plugs, wires and clamps/harnesses. Once you have all the wires where you want them then put on the harnesses and replace the AC Compressor.

Also, I would get some copper anit-sieze on the threads only on the new plugs. Do not over tighten, what ever you do. If it is dificult to screw on the plugs you probably cross threaded it, start again. Note the angle & Remember, you need to hear a click when you install the rubber plugs.

Take your time and enjoy the process.

[boxster03]

now that is excellent info. good job guys.

[RoninLB]

I like this Hazet.

the plug goes right into the head. No way of missing. Great for avoiding cross threading plugs.




I think a complete newbie should have someone around who has at least a little experience.

[mhackney]

Hey Ronin, I was looking for one of those! Found it at http://www.samstagsales.com/hazet.htm

Hazet #2505-2

Another day, another tool.

Cheers,
Michael

[RoninLB]

Originally Posted by mhackney

Hey Ronin, I was looking for one of those!

Another day, another tool.

the more you use it the better it gets.




from Mike's site

2505-2 Socket,
Spark Plug 3/8" dr
Expanding Spark Plug Socket,
13/16" (20.8mm) .
With a rubber insert to hold the plug. It is made with Chrome-Vanadium steel and mat chrome plated.

Push the release pin and this socket will adjust from 137.5mm to 157.5mm to 197.5mm.

HAZET suggests you use a model 8816GK flex head ratchet with this socket to get the most benefit.

$50.53

[oregonmon]

Thanks guys for the replies and especially Harry. Maybe see you on Sunday for autocross. Does everyone remove their A/C? Is it really necessary, the less parts I mess with the better I'm sure.

[DRACO A5OG]

You can leave it on but I hope you have skinny arms but guiding the wires under it will be a PITA.

It really is no big deal to remove the Compressor.At first I was a bit concerned but just remember not to over torque and insure 1/2 movement at the center of the belt. Plus you may want to replace the fan belt and AC belt WYIT (While Your In There)

[old man neri]

Originally Posted by oregonmon

Thanks guys for the replies and especially Harry. Maybe see you on Sunday for autocross. Does everyone remove their A/C? Is it really necessary, the less parts I mess with the better I'm sure.

No need to disconnect the hoses. I think most people when they change their plugs and wires are also doing an oil change and valve adjust so the AC is already out of the way. If you do everything at once it saves time I think. Also look at your fuel filter and air filter if you are changing your plugs/rotor.

[mhackney]

Absolutely DO NOT disconnect the AC hoses! All you need to do is remove the 3 AC Compressor mounting bolts. Put a big towel (folded several times) or better yet, an 18" square of 1/2" closed cell foam on the right fender and carefully lay the compressor on it without kinking the hoses.

Cheers
Michael

[tcar]

And, according to several Porsche wrenches - do NOT use Bosch PLATINUM plugs...

[oregonmon]

Originally Posted by tcar

And, according to several Porsche wrenches - do NOT use Bosch PLATINUM plugs...

Yeah, when I bought the car and my wrench changed the plugs from the PO, that's what they were and he recommended no platinum plugs.

[gtc]

I don't think you need the factory plug wrench. I use a craftsman 13/16" spark plug socket and it works fine. The key is to have a socket that holds the plug firmly - it's a pain if you drop it inside of the valve cover. You'll need a few different length extensions.
I buy the $2 NGK plugs at Autozone (pelican has them for $3.50). They're cheaper, work better, and last longer than the bosch platinums that came with my car.
Remember to check the plug gaps.