Spark plug backing out, Huh? |
|
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG.
This site is not affiliated with Porsche in any way. Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners. |
|
Spark plug backing out, Huh? |
jeffdon |
Jul 24 2012, 03:30 PM
Post
#1
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
A couple weeks ago, the car started running rough all of a sudden. Found that a wire was off No 1 plug, AND the plug was loose. Last had them out for a valve adjust begining of July, right before a 360 mile round trip to the sierras, with no issue.
Anyhow, pulled the plug, and put it back in, trying to feel for cross threading evidence, but it felt fine. Car ran great again. Now, today, on a 80 mile round trip, it loosened up not once, but twice. What could be causing this? |
benalishhero |
Jul 24 2012, 03:47 PM
Post
#2
|
Member Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States |
What torque value did you use?
|
jeffdon |
Jul 24 2012, 03:49 PM
Post
#3
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
|
r_towle |
Jul 24 2012, 04:15 PM
Post
#4
|
Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
It may be time for a plug fix kit
|
jeffdon |
Jul 24 2012, 04:24 PM
Post
#5
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
It may be time for a plug fix kit Only about 8k on rebuilt heads. Holes were welded up an retapped. That being said, I have heard the inserts are not that bad. Seem to recall hearing that 356 racers went with inserts because of all the pulling of plugs and re-installing. Who sells the kits? |
TheCabinetmaker |
Jul 24 2012, 05:52 PM
Post
#6
|
I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
Uh, before you freak out here, get a torque wrench and tighten them properly to the proper torque. Hand tight and a quarter turn ain't gonna cut it. I'm on my phone so don't have access to the torque spec. someone will be along to let you know what it is.
|
benalishhero |
Jul 24 2012, 06:00 PM
Post
#7
|
Member Group: Members Posts: 313 Joined: 28-November 07 From: Portland, Maine Member No.: 8,384 Region Association: North East States |
Uh, before you freak out here, get a torque wrench and tighten them properly to the proper torque. Hand tight and a quarter turn ain't gonna cut it. I'm on my phone so don't have access to the torque spec. someone will be along to let you know what it is. I think it's 15 ft. pounds edit: threads are prob stretched by now....... |
jeffdon |
Jul 24 2012, 06:07 PM
Post
#8
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
Ok, torquing to 18. Feels solid. Will check torque when cold, and see what happens.
|
TheCabinetmaker |
Jul 24 2012, 06:50 PM
Post
#9
|
I drive my car everyday Group: Members Posts: 8,304 Joined: 8-May 03 From: Tulsa, Ok. Member No.: 666 |
You might wanna check them all while your at it. How much more did it go than the quarter turn?
|
jeffdon |
Jul 24 2012, 07:15 PM
Post
#10
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
|
jeffdon |
Jul 26 2012, 03:53 PM
Post
#11
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
Well, its still backing out, so I am certain my threads are F'd or I have got a crack developing. Time to drop the engine.
Both heads were rebuilt once, with three out of 4 plug holes getting welded due to cracks. It will be interesting to see if this is the one hole that did not have a crack. I have access to a pair of 1.8 heads, and seem to recall they are a better design. Have them gone through is an option, I suppose, if there are advantages that anyone can point out. Of course, then I need to source new weber manifolds. Soooooo.....which way to go? Pull head, have hole repaired, reinstal? Have 1.8 heads gone through, swap out? Any other recommended "while I am in there" tasks? |
r_towle |
Jul 26 2012, 04:53 PM
Post
#12
|
Custom Member Group: Members Posts: 24,591 Joined: 9-January 03 From: Taxachusetts Member No.: 124 Region Association: North East States |
1.8 head need the plug moved, larger valves installed with new seats, and intake manifold studs removed, welded and moved to use as 2.0 liter heads.
I would pull the head , fix the plug with a threaded insert, put it back on and drive it. Rich |
ThePaintedMan |
Jul 26 2012, 06:40 PM
Post
#13
|
Advanced Member Group: Members Posts: 3,886 Joined: 6-September 11 From: St. Petersburg, FL Member No.: 13,527 Region Association: South East States |
(IMG:style_emoticons/default/agree.gif) Don't put anything past the Time Serts. Especially on a low-torque place like a SP hole. They make kits especially for them. Save yourself some money and do it that way. Might even do the other one while its out? John at Aircooled.net even rents Time Sert kits for a month at a time and the serts themselves are only a dollar or two a piece.
|
Lo-Fi Version | Time is now: 10th June 2024 - 03:35 AM |
All rights reserved 914World.com © since 2002 |
914World.com is the fastest growing online 914 community! We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ... |