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TR4/4A Reading my TR4's plugs [L-87YC]

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Tim Tucker

Tim Tucker

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Hi all,
I stumbled across an interesting plug reading article covering mixture and ignition timing. Here are my plugs from #1 and #4 cylinders.
+TR4 #1 Cylinder (1) - Copy.jpg
+TR4 #4 Cylinder (2) - Copy.jpg

the run mix looks OK (to me), the black on the electrode and the end of the threaded portion indicates a rich idle (per article). The location of color change on the ground strap seems to indicate my timing is too advanced (per article)?
I sure would appreciate feedback. I am running a pertronix but switching back to points (my TR6 unit died after ~9 years). However, I'm afraid my distributor has way too much side-side play. Is Advanced distributors still our best bet? I saw were jollyroger was selling a new Lucas made 25D4 for a MGB...could this be used? I have a Lucas made bushing, but I'm a bit concerned about damage to the body of the distributor? What's the best option for an old worn out distributor?
TIA for any feedback
Tim
 
I dunno, perhaps some insight in the article but far too much of an art for my liking. Check the timing by traditional methods for me. I never got beyond black and oily=oil in cylinder; wet with fuel= cylinder not firing, rusty= water in the tank.
Tom
 
They look good to me ; nice shade of tan perhaps a hair on the rich side . I wouldn't over think it this time of year. Double check your timing and find out exactly where you are at now, same with the carbs. When everything is working well on a car you get to see what good parts look like and that helps when it doesn't run properly.
 
Tim Tucker said:
Plug Reading Article

I didn't make it stand well enough in the original post. clicking on "article" would take you there...
Click to expand...

I never saw a technique that read so much into and from the plugs. Mix at idle vs speed, timing too advanced or retarded...everything but 'your weight & your fate'.

I'd agree your plugs look okay. I know I always seem to have some black around the bottom of the threaded portion of the plugs so I mainly read the tip. I suspect modern fuels have somewhat comprised the value of reading the mixture on the plugs.
 
I had to laugh while reading the article and seeing the comment about the "trashed combustion chambers" and melted plugs in Bob Riggle's Hurst Hemi Under Glass. If you're a fan of Jay Leno's Garage and/or have been anywhere near almost any form of social media recently, you know that, right now, combustion chamber problems are well down on the list of problems facing that most classic of drag racing machines! :(
 
In my experience with 2 strokes, the peanut butter color is what you strive for in a 2 stroke. So what I see in your plugs is a slight amount of oil consumption. The peanut butter line on your insulator is probably oil seeping in from your valve guide. Both the plug and the guide are stationary so the oil just settles on one spot. I wouldn't worry for a second on these plugs. A slight amount of oil consumption was built into these engines for a reason.
 
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