Click on image for the lowdown. 
====
| | | Forums66 Topics128,087 Posts1,056,115 Members48,435 | | Most Online14,466
Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
| | THANKS!
For helping keep this great
old truck web site
on the Internet for over 30 years! and not clogged down
with Ads!  Again, thanks!
| | | | Joined: Sep 2007 Posts: 393 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 393 | I've done a search and can't seem to find much about the Colortune spark plug tool for diagnosing idle mixture(other than someone asking about it (as I am) or someone stating what color theirs was showing)? Is this a tool that is worthwhile having in the tool box? Any one have any experience with this? I have a 47 1/2 ton with a Carter W-1. Thanks.
It's a small world, but I wouldn't want to paint it.
| | | | | Joined: Sep 2006 Posts: 2,393 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 2,393 | I have one. Don't like it much. It's easier just to examine the spark plugs for air/fuel mixture results.
Drew
| | | | | Joined: Feb 2004 Posts: 29,796 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,796 | It's a P.T. Barnum special. (There's a sucker born every minute) If you had some way to look at it when under load out on the road, it might be different, but riding the fender with the hood open gets hazardous to your health!
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | Can you use a digital camera to watch/record it under the hood as you drive?
Grigg | | | | | Joined: Feb 2004 Posts: 29,796 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,796 | I've used a set of thermistors mounted in headers to monitor exhaust port temperature during a dyno run. 2,000 degrees F. at full throttle is considered to be ideal for a race engine. That's usually about a 12.5:1 air/fuel ratio, far too rich for good fuel economy. For a road test, something similar might be possible, but I don't really see the advantage over just installing a clean set of plugs and doing a 50-mile test run. With a pre-planned route involving some hills to climb, city and highway driving, etc., then pulling the plugs and looking at the color of the insulators should give a much better indication of correct mixture.
Jerry
Last edited by Hotrod Lincoln; 07/15/2010 5:35 PM.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Sep 2007 Posts: 393 'Bolter | | 'Bolter Joined: Sep 2007 Posts: 393 | Thanks for the input. Just what I need to make a decision.
It's a small world, but I wouldn't want to paint it.
| | | | | Joined: Mar 2007 Posts: 64 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2007 Posts: 64 | If you really want to tune an engine right, invest the money in a wide band oxygen sensor. You'll need to put an oxygen sensor bung in the exhaust pipe a few inches below the manifold. Install the sensor and portable output unit and you can drive down the road and record several minutes of readings which convert to air/fuel ration. You remove the oxygen sensor itself when you're through testing and plug the bung. But it's there for the next time if you need to use it. Joe | | | | | Joined: Jan 2008 Posts: 493 Shop Shark | | Shop Shark Joined: Jan 2008 Posts: 493 | I have one that I got years ago for the MG. It's crap. But that is just my opiniion. | | | | | Joined: Feb 2001 Posts: 1,096 'Bolter | | 'Bolter Joined: Feb 2001 Posts: 1,096 | LOL at you guys.... I've had great success with my color tune , especially on multiple carbs setup. Even the lowly W-1 can be set very nicely with the color tune. You know, for diagnosing idle mixture , no driving down the road is necessary...........  Rusty , the colortune should have a very large color chart included in the box , to enable diagnosis of what you are able to see thru the plug. Of course there are other ways to tune your rig , it's just that this tool works too.
Last edited by Dusty; 07/17/2010 4:50 AM.
| | |
|
|
