spark plug tubes

[phillipj]

Going to replace the leaking spark plug tubes on my 99 996 tomorrow. My mechanic will be doing the work and i will be there to observe. I would have done it myself but without a lift it seemed unwise.

I will pass on any valuable information after the job is complete in case anyone has this job facing them

:renntech:

Phillipj

[1999Porsche911]

Make sure he replaces the O rings with the tubes. Bad O rings most commonly cause the leaks.

[KevinMac]

Make sure he replaces the O rings with the tubes. Bad O rings most commonly cause the leaks.

U sure U need new tubes. bet the leaks are just the o rings!

[vette67]

How did you determine that you need new tubes /o-rings? Compression test? Porsche diagnostic scan?

[phillipj]

Thanks for everyones input.

Loren and RFM helped me out on this topic so I knew what parts to order.

Yes I have the new O rings (small and large) and the special Porsche lubricant. The tubes need to be replaced because they are leaking badly. A visual inspection confirms this. I will also remove my cam cover bolts (one by one) and treat them with silicone sealant because they seem to be leaking as well.

I will let everyone know how it goes. :rolleyes: :rolleyes: :rolleyes:

Phillipj

[KevinMac]

Thanks for everyones input.

Loren and RFM helped me out on this topic so I knew what parts to order.

Yes I have the new O rings (small and large) and the special Porsche lubricant. The tubes need to be replaced because they are leaking badly. A visual inspection confirms this. I will also remove my cam cover bolts (one by one) and treat them with silicone sealant because they seem to be leaking as well.

I will let everyone know how it goes. :rolleyes: :rolleyes: :rolleyes:

Phillipj

How does a metal tube leak unless somehow damaged. If u did not damage it, U are seeing oil residue from the "O" rings! I con't fathom how a tube can leak just on it's own!!

Edited February 20, 2008 by KevinMac

[RFM]

The last generation O rings are larger, that's why he needs new PLASTIC tubes.

[phillipj]

Thanks for everyones input.

Loren and RFM helped me out on this topic so I knew what parts to order.

Yes I have the new O rings (small and large) and the special Porsche lubricant. The tubes need to be replaced because they are leaking badly. A visual inspection confirms this. I will also remove my cam cover bolts (one by one) and treat them with silicone sealant because they seem to be leaking as well.

I will let everyone know how it goes. :rolleyes: :rolleyes: :rolleyes:

Phillipj

How does a metal tube leak unless somehow damaged. If u did not damage it, U are seeing oil residue from the "O" rings! I con't fathom how a tube can leak just on it's own!!

The tube is not metal it's plastic. It's not the tube that leaks it's the 0 rings. The tubes are only $7 bucks. Better to replace them as well.. This is a pretty common ailment for high mileage 996 motors. This is all new to me. None of my other car(BMW's, Benz) had "spark plug tubes!

A big thanks to RFM for all of his input and help on this subject. Very much appreciated!!! :D

Phillipj

Edited February 20, 2008 by phillipj

[pjalexandre]

Hey Phillip,

it is common to check the tubes out when you 1st replace your plugs. The old style o rings leaked and needed to replaced wholesale with the newer style.. However the tubes themselves do crack and leak that way as well. I had 2 cracked ones.

This is actually a very very easy job if you remove your mufflers. Otherwise it is a huge PITA.

Best...

-Paul

[phillipj]

Update,

Spark plug tubes replaced and cam cover bolts re-sealed. Had oil changed as well. Provided all parts ($60 bucks less oil) and my mechanic charged me $225 bucks. Very fair I thought.

Getting the old tubes out was kind of a bear but putting the new ones in was easy.

Just got the car back and wound it up to high revs. (This is when it would leak before the repair.) No leaks on the exhaust and shameful smoke this time!. Dry as bone so far! :clapping:

Will inspect it again in a few days.

This is a pretty easy DIY if you have a lift or want to remove the wheels and mufflers.

Thanks for everyones input! :renntech:

Phillipj

[Izzy]

This is what the tubes and tube with ring look like:

It does make it easier to remove the rear wheels, bumper, heat shield, mufflers. To my banana fingers it makes the job enjoyable, and only adds about 1hr time to a DIY like me.

To get the tubes out, you can use a tool like the one below. All you do is insert the custom designed red part into the tube (without the spark plug in), and pull the special metal protrusion away from the engine. It is part number 996-izz-y34-001, for sale from me for $187.34 ;) .

[vette67]

This is what the tubes and tube with ring look like:

It does make it easier to remove the rear wheels, bumper, heat shield, mufflers. To my banana fingers it makes the job enjoyable, and only adds about 1hr time to a DIY like me.

To get the tubes out, you can use a tool like the one below. All you do is insert the custom designed red part into the tube (without the spark plug in), and pull the special metal protrusion away from the engine. It is part number 996-izz-y34-001, for sale from me for $187.34 ;) .

Do you offer an upgraded model? It could be worth $212.50 or more if you used a Craftsman scewdriver.

:lol: :lol: :lol:

[phillipj]

This is what the tubes and tube with ring look like:

It does make it easier to remove the rear wheels, bumper, heat shield, mufflers. To my banana fingers it makes the job enjoyable, and only adds about 1hr time to a DIY like me.

To get the tubes out, you can use a tool like the one below. All you do is insert the custom designed red part into the tube (without the spark plug in), and pull the special metal protrusion away from the engine. It is part number 996-izz-y34-001, for sale from me for $187.34 ;) .

Izzy,

I found the same tool online for $180.00 Made out of aircraft quality plastic. Shame on you for the needles mark-up :D :lol: :D

Phillipj

[Heidster]

If you see oil build-up here...

Hmmm...I wonder why oil was leaking?

I'd guess it was a "factory original" as I don't think previous owner(s) ever messed with the tubes. Looks like somebody messed up the tips on the coil extensions too.

I guess I could have worse issues...glad Jeff @ Sunset is there to ship more parts.

FYI the tubes themselves seem to be intact but for ~ $7/tube just change them along with new O-rings.

[CosmosC4S]

Someone posted on rennlist about an inexpensive tool they got from Walmart for this job.

That was the first time I've heard of a spark plug tube, that leaks oil. Is that tube where the spark plug inserts into? Would someone care to enlighten me on the mechanics behind this tube? I'm just puzzled as to how a tube with oil would have anything to do with spark plugs? :huh: Is this specific to our Porsche engines, or does every engine has them? Sorry for my dumbness, but I've never heard of nor seen such a tube before.

[deanslist.us]

Someone posted on rennlist about an inexpensive tool they got from Walmart for this job.

That was the first time I've heard of a spark plug tube, that leaks oil. Is that tube where the spark plug inserts into? Would someone care to enlighten me on the mechanics behind this tube? I'm just puzzled as to how a tube with oil would have anything to do with spark plugs? :huh: Is this specific to our Porsche engines, or does every engine has them? Sorry for my dumbness, but I've never heard of nor seen such a tube before.

+1, I too do not understand and would like to so that I can check my own.

[Loren]

If they are not leaking into the spark plug channel or to the outside of the engine - then don't worry about them as they are likely the newer design.

In the Porsche engine design the spark plugs sit in the middle of the heads between the two camshafts - so the spark plug is kept seperate from the oil by the tubes. Besides you need to be able to access the spark plugs without removing the heads. Older VW and Porsche designs were similar except they ran the the lifter pushrods through oil tubes. (and they leaked too - LOL)

[deanslist.us]

If they are not leaking into the spark plug channel or to the outside of the engine - then don't worry about them as they are likely the newer design.

In the Porsche engine design the spark plugs sit in the middle of the heads between the two camshafts - so the spark plug is kept seperate from the oil by the tubes. Besides you need to be able to access the spark plugs without removing the heads. Older VW and Porsche designs were similar except they ran the the lifter pushrods through oil tubes. (and they leaked too - LOL)

Thanks Loren, very to-the-point. As far as leaks, would I see a visible drip on the floor, or just a helluva lot of buildup in the spark plug tubes? Reason I ask, is that I changed my plugs 1.5 years ago and I remember cleaning oil gunk buildup off of a couple of the long skinny tubes that are connected to the coils. I thought it was just residual crap from the RMS that we discovered was leaking as well, which also never left a drop of oil on my garage floor. Car uses oil, but usually only after getting on it for a good while, like a long fast tour or a track day.

I remember the oil return tubes on my 76 911 used to leak, till I updated them with the extending ones.

Edited May 7, 2009 by deanslist.us

[Loren]

Only way (IMHO) that you can tell where an oil leak is coming from is to thoroughly clean the area and then run the car until you see the start point of the leak. Sometimes they surprise you with their actual location.

[function12]

Someone on another board said a 1" boat plug works great to remove the tubes.

I had a a tube leak and I did have a small amount of oil on the garage floor. Plus it cause the coil pack to miss fire.

Edited May 8, 2009 by function12

[Heidster]

Just to add a few more bits of info for those thinking about doing this fix. My car is a 1999 C2 6Spd actually built in (gasp!) Jan '98. Original motor, no other issues: ~45K miles. So the O-rings were the "original" design that was upgraded later.

As far as symptoms of leaks you may notice oil gathering at the bottom of the Cam covers (gravity does this) as in my above pic. It stars by just looking a bit dirty. Eventually I was getting drips to the garage floor. So time for action. I also noticed some oil on the inside of a few of the tubes. Most likely from the smaller/inner O-ring. So if, when changing plugs, you see oil on the spark plug socket extentions...it's probably those inner rings. See above pics as 2 of them were not seated correctly.

As far as extracting the tubes...I used both Izzy's "tool" and had a 1/2" 17MM long socket that had the perfect diameter as the tubes taper down to the spark plug. I haven't actually installed the new ones as some of the spark plug socket extensions (PN: 996.602.103.01 for up to '01) were a bit buggered up. I should get them today from Sunset Porsche. Those guys are great.

Here's another tell-tale shot:

I'll post more tips for the DIY's after the reassembly this weekend.

[Heidster]

Here is a pic of old tube, on the right, with 17MM long socket improvised removal tool. On the left is the new tube with O-rings gooped up with the special Porsche grease. Insertion is 2 step. 1st is just two thumbs and a bit of force and you'll feel it pop in. Then find a 27MM socket as it fits the face of the tube perfectly. I got 5 of 6 in with just more hand pressure, the 6th just took a whap of a rubber hammer. Thanks to all those before me that provided info for this fix. Time will tell if the leaking stops.

[ninsei]

Hi. So what additional work is required to change the tubes (and O rings) if one is about to change spark plugs?

[Heidster]

Hi. So what additional work is required to change the tubes (and O rings) if one is about to change spark plugs?

If you're changing spark plugs you've removed the mufflers and pulled the coils out so its just pulling out the old tubes and prepping/inserting the new ones. Maybe an extra 1/2 hour of time.

[logray]

Can anyone recommend an alternative lube for the tube o-rings? The dealer quoted me a huge sum of money for a giant tube, which is great if I was an engine re-builder.

The drive to the dealer to get a small amount (hopefully free) is a 2 hour round trip. Would rather go to the local Napa.

Thanks!