Change spark plugs and tubes? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Bradster · 08-18-2010, 04:44 PM

I will soon need to change the spark plugs in my 97 base as I am approaching 90K. Do most change the plugs, tubes, and o-rings -- or just the plugs?

Thanks!

Bradster

BudmanV24 · 08-18-2010, 04:54 PM

Are the o-rings on the tubes leaking? If not, then I wouldn't mess with them. And don't get platinum plugs. They reduce throttle response. Go with copper.

gschotland · 08-18-2010, 10:36 PM

Your car's now 13 years old w/~90k miles. A bad O-ring's no big deal, but a cracked or broken tube can be a big PITA, maybe even costly. The physical properties of almost all thermoplastics (in a former life I was an engineer in the plastics industry) will degrade with extended exposure to heat cycles. The tubes have been known to fail, which is presumably why you asked the question.

Why risk having a potentially costly failure at the wrong time when you can quickly and easily swap out all the o-rings and tubes for only $75 bucks while you're in there installing the plugs? Excellent, EZ to follow instructions at http://www.pedrosgarage.com/Site_3/Change_Spark_Plugs_%26_Tubes.html

BTW, I agree w/BudmanV24, stay away from exotic or "improved" plugs. The OEM Beru's are fine, if a little pricey (I'm happy with them); the Bosch plugs Pelican sells for $4.50ea are good choice as well. Pedro's got part numbers on his plug change DIY article should you want to buy local.

Bradster · 08-19-2010, 03:55 AM

Thanks to you both! I appreciate the input.

Mike_Yi · 08-20-2010, 09:17 AM

I just did my 60k and changed the plugs and o-rings. I didn't replace the tubes. It's a pretty easy job and does not take long. If you have any question, go ahead and do it.

Dave928 · 08-20-2010, 10:29 PM

there's no more obvious WYIT than this, you ARE right there.

just change them...

KevinH1990 · 08-21-2010, 09:26 AM

I'm planning to replace my O-Rings when I change the spark plugs in about a month. Is it better to change the plugs when you have the tubes out, or is it better to pull the tubes, replace the O-Rings and reinstall the tubes before changing the plugs?

Thanks

Mike_Yi · 08-21-2010, 02:50 PM

Change the plugs while the tubes are in. That way, if the plug slips out of the socket, it doesn't fall into the crankcase. Change the tubes with the plugs out.

In other words, pull plug, pull tube. Insert new tube, then insert new plug.

Bradster · 08-21-2010, 03:56 PM

Good advice. Thanks again!

Mark_T · 08-21-2010, 04:21 PM

Here's a tip for you on the tubes - use the mandrel from a 1" drum sander to pull them out.

I tried Pedro's suggestion of using a 1" boating transom plug, but I had trouble getting it tight enough to grip and by halfway through the job the transom plug was trashed. The drum sander mandrel fit better, has a bigger gripping surface, and is much easier to tighten up.

Mark

Mike_Yi · 08-22-2010, 08:09 PM

I had no problem with the boat plug. Got it from Cabella's.

Dave928 · 08-23-2010, 01:03 AM

+ on the boat plug.

KevinH1990 · 08-23-2010, 08:18 PM

Quote:

Originally Posted by Mike_Yi

Change the plugs while the tubes are in. That way, if the plug slips out of the socket, it doesn't fall into the crankcase. Change the tubes with the plugs out.

In other words, pull plug, pull tube. Insert new tube, then insert new plug.

Thanks. That process makes sense. While I may have figured it out on my own, I'm glad I didn't have to learn by having an unpleasant experience.

It just proves the old saying - there are no stupid questions.