Guest Anonymous

Spark Plug Drama

12 posts in this topic Last Reply

Recommended Posts

Guest Anonymous

Hey Guys,

I'm trying to replace my spark plugs (Bosch WR8DC, what I pulled outta the car) but having some issues with parts.

The car: 1975 BMW Auto 2002

I need a spark plug with a screw on top because my plugs are threaded, most of the ones Kragen and Autozone say fit my car have a cap on top of the screw.

I picked up some Bosch's about 30 minutes ago with WR8DP on them, they have a screw with the removable cap, however the gap size is well over the recommended .0024, it sits at .0034. Do i re-gap this somehow? The gap-size on the one I pulled out of the car is at 28ish.

I've looked at the NGK BP5ES, but the cap is not removable and thus will not fit on my plug wires.

Help please!!!!

Which part do I need?

Share this post


Link to post
Share on other sites

Take the "P" (Platinum) plugs back to the pimply-faced kid at Autozone, and get the correct COPPER plugs. I don't care *what* their "catalog" says. I never run Platinums in old BMWs - EVER!

Most places will not have copper W8 (or 9) DC plugs. Support your local 2002 specialist parts vendor on-line, instead. You're paying for their knowledge when you do that. Worth the price...and the mail order wait.

I gap most plugs at about .028 for std points ignition, and have used gaps as large as .032/.034 for electronic ignitions. :)

Hope this helps!

paul wegweiser

Share this post


Link to post
Share on other sites
Guest Anonymous

Ok - so pretty much get the WR8DC like the ones I took out of the car.

This is my DD so waiting for the mail is very difficult!

Share this post


Link to post
Share on other sites

I can totally relate! I drove Emily (my 73 02) 70 miles EVERY day for years - as my only car. I remember the stress of replacing strut bearings (and many other things) in the parking lot behind my apt as the sun sets on a Sunday night = no fun).

Install the platinum ones as a temporary measure til the correct ones arrive, would be my advice.

If she's your (only) daily driver, I'd suggest the following in your spares kit (takes up little room, fits in the bottom of a closet, or in the trunk, and not greasy) :-)

4 W8DC spark plugs

correct distributor cap

distributor rotor

correct ignition points

spare bakelite spark plug connectors (I harvest used ones, when I can)

fan belt

a couple hoses (esp the radiator ones, and the short one from water pump to thermostat)

BMW (or Wurth) hoseclamps

ass't "European" type fuses

scrap of fine sand paper to clean points/plugs in a pinch.

I'm sure there's more - but these are good basics. Plugs can foul suddenly for all kinds of reasons, and caps/plug connectors can crack - so I always have 'em on hand.

Share this post


Link to post
Share on other sites

No, you do not want to use Bosch WR8DC plugs. The "R" is for resistor, and you have the resistor function in the plug connector, which is why you do not want the "R" designation plug. As advised above, go to one of the online vendors listed in the above under "Links" to find W8DC plugs. Or use the NGK BP5ES plugs you found. The cap is removable - it's just screwed on to the top. Maybe when you tried to remove it was tight, but they'll unscrew. Many on this board run that plug. I'm currently running BP6ESs in my ' 75 2002A, but I have a modified, higher-compression engine in my car.

Good luck,

Bob napier

Share this post


Link to post
Share on other sites
Guest Anonymous

Thanks, Bob.

The caps seemed as though they were impossible to remove, however, I didn't try to use an adjustable wrench or any tools, just my hands. The Bosch caps unscrew with no effort at all.

Your post is somewhat confusing. You said I shouldn't use the WR8DC but I should find a vendor that carries them, could you elaborate?

The NGK are readily available - you are positive the caps come off?

Keep in mind I have the stock plug wires that have a thread that receives a screw.

Share this post


Link to post
Share on other sites
Guest Anonymous
Thanks, Bob.

The caps seemed as though they were impossible to remove, however, I didn't try to use an adjustable wrench or any tools, just my hands. The Bosch caps unscrew with no effort at all.

Your post is somewhat confusing. You said I shouldn't use the WR8DC but I should find a vendor that carries them, could you elaborate?

The NGK are readily available - you are positive the caps come off?

Keep in mind I have the stock plug wires that have a thread that receives a screw.

Nevermind about the confusion of WR8DC and W8DC, I noticed you were talking about the "R" in WR8DC.

Share this post


Link to post
Share on other sites
Guest Anonymous
No, you do not want to use Bosch WR8DC plugs. The "R" is for resistor, and you have the resistor function in the plug connector, which is why you do not want the "R" designation plug. As advised above, go to one of the online vendors listed in the above under "Links" to find W8DC plugs. Or use the NGK BP5ES plugs you found. The cap is removable - it's just screwed on to the top. Maybe when you tried to remove it was tight, but they'll unscrew. Many on this board run that plug. I'm currently running BP6ESs in my ' 75 2002A, but I have a modified, higher-compression engine in my car.

Good luck,

Bob napier

Oh yeah, will the NGK BP5ES be pre-gapped to .0024?

Share this post


Link to post
Share on other sites

Always gap your own plugs. One type of plug may fit numerous different cars, all with different gap specs.

How to set plug gap - NGK's website has a tutorial. It's quite easy. While you're buying your NGKs, buy a set of gauge wires too.

Look in "proper gapping" at the following site:

http://www.ngk.com/faqmain.asp

Good luck!

Share this post


Link to post
Share on other sites
Guest Anonymous

Awesome, didn't know I could tap the plug to tighten the gap then resize to fit.

NGK's webpage didn't say anything about removable terminal nuts, are they for sure removable on the BP5ES?

Thats my last question then i'm off to pick up the right ones!

Share this post


Link to post
Share on other sites

Those terminal nuts on the BP5ES are for sure removable. I just bought some of these plugs and I could unscrew mine by hand. The terminal nuts look like the ones on this bosch plug right?

post-391-13667605229676_thumb.jpg

Share this post


Link to post
Share on other sites
Guest Anonymous

Yes, i'm picking up the BP5ES as we speak.

Thanks for all the input, man I love this forum!

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now