DIY on changing spark plugs in M50 engine

[ktteoh]

folks, i want to change my current plugs from bosch super (2 electrodes) to bosch super 4 (4 electrodes).

i plan to do it when the engine is cold early in the morning.

i have done some reading up and see frightful stories like high voltage, "fragile" direct ignition coils etc.

some questions i have:
1. how do i open up the (BMW logoed) engine cover? how many screws and where?

2. do i need to disconnect the battery?

3. what are the correct steps to separate the ignition coil modules from the spark plug? - can this be done one plug at a time?

4. when tightening the plug, after tightening by hand, how much turns should i add using the wrench (i don't have a torque wrench).

5. any pictorials guide anywhere?

6. any other gotchas i should be aware of?

7. how long should this take for all 6 plugs?

[t.wak]

http://bmwe34.net/e34main/maintenanc...park_plugs.htm

[ktteoh]

the one on bmwe34.net has no pictures and i think it refers more to m30 engine rather than m50 engine which have (additional complexity of) direct ignition coil on top of each plug.

anyone with clues for m50 plug renewal for newbies?

[DaveVoorhis]

It's a trivial job. You do not need to disconnect the battery, but it's probably a good idea to do so any time you're working under the hood/bonnet.

Use a small screwdriver to pop the two screw caps off the larger plastic engine cover. Underneath each, you'll find a nut. Undo each nut. Then temporarily remove the oil fillter cap, lift off the engine cover, and replace the oil filter cap.

You'll see six coil packs, each secured with two nuts. Starting at the front of the engine, undo the nuts on the first coilpack. The coil pack will pop up slightly. Remove the coil pack from the plug.

Look down the plug hole -- if it's full of oil, your valve cover gasket needs to be replaced, which is another easy job.

Remove the plug using an appropriate socket. Install the new plug, following the torque instructions found on the new plug's box. Re-install the coil pack, making sure to restore any grounding straps to their original locations.

Repeat the above for all six. The whole job will probably take about a half hour to an hour if you've never changed plugs before.

[e34.535i.sport]

Changed the sparks for the first time myself recently - after a lot of research. I Think the general directions have been layed out so i only have one other piece of advice - make sure you get some copper based anti-sieze to put on the threads when you're putting them back in. (Ive heard things can get problematic if you dont use it!).

Oh and a lot of people seem to suggest sticking with the stock plugs gives much better results but personal choice. Good luck.

[Tiger]

Time and time again...Bosch plus 4 plugs makes BMW engine runs like crap. Don't bother.

[Dr. evil]

i've used bosch platinum 4 for about a year and have had Zero Problems.

Different strokes for different folks.

[DaveVoorhis]

In case there's any confusion, I meant the oil filler cap, not "fillter" or "filter" as I wrote.

[Denton]

Changed the sparks for the first time myself recently - after a lot of research. I Think the general directions have been layed out so i only have one other piece of advice - make sure you get some copper based anti-sieze to put on the threads when you're putting them back in. (Ive heard things can get problematic if you dont use it!).

Oh and a lot of people seem to suggest sticking with the stock plugs gives much better results but personal choice. Good luck.

+1 on that!

[fujioko]

Since you'll be saving a ton of money by doing the work yourself, Why not spend a lot more and get a set of Denso Iridium plugs. You'll sh*t twinkeys when you see how much they cost.. They are worth every penny!

Bosch also makes a decent tosters and coffee machine.. but their +4 plugs suck.