Plug reading, Hows it look? |
|
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. |
|
Plug reading, Hows it look? |
jeffdon |
Aug 9 2010, 03:58 PM
Post
#1
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
Getting some snuffling through the carbs, still feels sluggish. I think i am pretty close on mixture. Got a feeling there is some movement back and forth on my bellcrank which may be making the two halves of the engine "fight" each other. How she look?
Attached image(s) |
tornik550 |
Aug 9 2010, 04:20 PM
Post
#2
|
Senior Member Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None |
Looks lean to me.
|
tornik550 |
Aug 9 2010, 04:24 PM
Post
#3
|
Senior Member Group: Members Posts: 1,248 Joined: 29-January 07 From: Ohio Member No.: 7,486 Region Association: None |
Heres a thread that I started recently. Some of the responses were very helpful to me. (I am obviously no expert so my "it looks lean to me" comment should be taken with a grain of salt).
http://www.914world.com/bbs2/index.php?act...=2&t=109442 |
jeffdon |
Aug 9 2010, 04:30 PM
Post
#4
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
Heres a thread that I started recently. Some of the responses were very helpful to me. (I am obviously no expert so my "it looks lean to me" comment should be taken with a grain of salt). http://www.914world.com/bbs2/index.php?act...=2&t=109442 Thanks man. Some good info in there. |
'73-914kid |
Aug 9 2010, 05:47 PM
Post
#5
|
Senior Member Group: Members Posts: 1,473 Joined: 1-November 08 From: Vista, CA Member No.: 9,714 Region Association: Southern California |
If the engine seems to chirp or cough, chances are that it's lean.. hence a "lean pop-back". As far as the ceramic insulator, it looks lean to me. lean enough to burn off any residual carbon left by un-leaded fuel as well..
What's your ignition system and plug gap? |
jeffdon |
Aug 9 2010, 08:19 PM
Post
#6
|
Senior Member Group: Members Posts: 1,094 Joined: 24-October 06 From: oakland, ca Member No.: 7,087 Region Association: None |
If the engine seems to chirp or cough, chances are that it's lean.. hence a "lean pop-back". As far as the ceramic insulator, it looks lean to me. lean enough to burn off any residual carbon left by un-leaded fuel as well.. What's your ignition system and plug gap? Pertronix on the igy. Gap is 28 thou. I think |
rickthejetman |
Aug 9 2010, 08:25 PM
Post
#7
|
Member Group: Members Posts: 90 Joined: 5-May 09 From: victorville ,ca Member No.: 10,335 Region Association: None |
white ash indicates lean but its not heavy so i'd say slightly lean. how long has this plug been in use? since your aircooled you want slightly rich. i'm an airplane mechanic an i can tell when an owner has been trying to get "better fuel economy" lol. aircraft owners are the cheapest people on the planet.
|
Project 6 |
Aug 9 2010, 08:28 PM
Post
#8
|
large member Group: Members Posts: 359 Joined: 30-December 02 From: Utah Member No.: 51 Region Association: None |
slightly lean is like being slightly pregnant....
|
rickthejetman |
Aug 9 2010, 08:57 PM
Post
#9
|
Member Group: Members Posts: 90 Joined: 5-May 09 From: victorville ,ca Member No.: 10,335 Region Association: None |
|
SLITS |
Aug 9 2010, 08:58 PM
Post
#10
|
"This Utah shit is HARSH!" Group: Benefactors Posts: 13,602 Joined: 22-February 04 From: SoCal Mountains ... Member No.: 1,696 Region Association: None |
To get an accurate plug reading, you have to do a few hot laps (preferably on a track)or a run down the freeway. When you decide you've had enough, 3 laps, you kill the engine entering the pits. Before the engine cools down, you pull the plugs, carefully.
That said, a light brown to medium coloration to the center electrode is desirable. White deposits are the burned additives in street gas. A bright white center electode is lean; Black is rich. That's what I know .... |
charliew |
Aug 9 2010, 10:18 PM
Post
#11
|
Advanced Member Group: Members Posts: 2,363 Joined: 31-July 07 From: Crawford, TX. Member No.: 7,958 |
The only way I ever got a reliable plug reading was to kill the motor at wot and immediately push the clutch in and coast to a stop and pull the plugs, all of them. It didn't need to still be hot just no running after wot to get a real under load reading. It looks like it was just put in and run about two miles to me and deffinately not as rich as a aircooled motor should be. It looks like it got pretty hot. You also didn't say what fuel it is burning.
|
ME733 |
Aug 10 2010, 07:44 AM
Post
#12
|
Senior Member Group: Members Posts: 842 Joined: 25-June 08 From: Atlanta Ga. Member No.: 9,209 Region Association: South East States |
Getting some snuffling through the carbs, still feels sluggish. I think i am pretty close on mixture. Got a feeling there is some movement back and forth on my bellcrank which may be making the two halves of the engine "fight" each other. How she look? .................Looks slightly lean...plug gap appears ok....And it appears that the greyish coloration on the spark plug threads is ..anti-sieze...and the plug has not run very long. Anti-sieze SHOULD be used on the spark plug threads., Especially if you know that you will be removing and installing plugs from a HOT engine. Removing plugs from a HOT engine is when the heads aluminum spark plug threads are prone to damage...cracking, breaking off, stripping etc...I hope you used, or will use, anti-sieze, as well as everyone else. |
Lo-Fi Version | Time is now: 16th May 2024 - 08:11 PM |
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 ... |