How about this spark plug color?
03-07-2009 | 11:09 AM
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From: pohangkyung buk, KOREA, REPUBLIC OF (KOR)
How about this spark plug color?
Hi everyone?
My engine is DA50R and bolly 23-8, mtwcan highrpm 6700.
How about my spark plug color?
My engine is DA50R and bolly 23-8, mtwcan highrpm 6700.
How about my spark plug color?
03-07-2009 | 11:16 AM
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From: Altaville,
CA
RE: How about this spark plug color?
A bit overpropped for the type of oil you are using. Heat is building deposits on one side of the plug. That will more than likely be the exhaust side. As those deposits flake off they scratch the rings and cylinder walls along the exhaust port side.
The cure? Smaller prop, limit high speed runs, run the engine ritcher, find an oil and or gas that burns cleaner. Keep the exhaust gas temps lower.
The cure? Smaller prop, limit high speed runs, run the engine ritcher, find an oil and or gas that burns cleaner. Keep the exhaust gas temps lower.
03-07-2009 | 03:47 PM
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From: Burtchville,
MI
RE: How about this spark plug color?
ORIGINAL: hanibaram
Hi everyone?
My engine is DA50R and bolly 23-8, mtwcan highrpm 6700.
How about my spark plug color?
Hi everyone?
My engine is DA50R and bolly 23-8, mtwcan highrpm 6700.
How about my spark plug color?
I would be very happy with that plug. Just FYI, pros, like Champion Spark Plug Technichians don't read the tip of the plug porcelain they look at the area where the porcelain and the metal plug body meet way down inside the plug. I don't bother to get a high powered lighted magnifier myself. They look for a little ring of soot just above the point where the porcelain and the metal plug body meet. This is the place where you can check your mixture. If you see little silver balls down ther look out, it's usually portions of your piston crown and you may want to richen your main jet or needle adjustment. The tip of the plug porcelain will tell you if your plug is of the correct heat range. Well, that's what I've read.
Bill
Bill
03-07-2009 | 05:23 PM
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From: iola,
TX
RE: How about this spark plug color?
You are correct Ram Jet. To truely read a plug you should be looking way down at the base of the insulater. But the upper portion gives you a general idea of how you mixture is. Just not a true accurate reading. To get an accurate reading you must also accelerate at full throttle, cut the ignition off from full throttle, return the thottle to idle postion and then check the plug. Atleast that is the way I was told to do it from some old sprint car racers.
03-07-2009 | 06:12 PM
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From: iola,
TX
RE: How about this spark plug color?
Piston flakes can also be seen all around the insulater upper portion as shiny, sparkly specs. An indication that you are cooking your engine.
03-07-2009 | 06:15 PM
#12
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RE: How about this spark plug color?
This is the final say on plug reading.
I made a nice story of it on my forum, check [link=http://www.prme.nl/forum/viewtopic.php?t=10]here.[/link], or check out TSR racing, who made this chart for reading plugs.
This is a set of plugs I dismantled to show the difference between cold plug and rich mixture.
Plug 1 is slightly lean, as indicated by the head temperature.
plug 2 is slightly richer, the black ring still is not as high as 1/4 isolator length
plug 3 is too rich. The black has crept up to 1/3rd isolator length.
plug 4 is too rich, but heat range is OK (champion DJ7Y)
Plug 5 is too lean (no black ring) It also is too cold (champion DJ6J black nose)
plug 6 is right mixture as shown by mixture ring, but too cold.
The head temperatures are quite high, because measurements were made on a stationary test stand. In a plane, with baffles installed, temperatures drop 20 - 40 degrees.
I made a nice story of it on my forum, check [link=http://www.prme.nl/forum/viewtopic.php?t=10]here.[/link], or check out TSR racing, who made this chart for reading plugs.
This is a set of plugs I dismantled to show the difference between cold plug and rich mixture.
Plug 1 is slightly lean, as indicated by the head temperature.
plug 2 is slightly richer, the black ring still is not as high as 1/4 isolator length
plug 3 is too rich. The black has crept up to 1/3rd isolator length.
plug 4 is too rich, but heat range is OK (champion DJ7Y)
Plug 5 is too lean (no black ring) It also is too cold (champion DJ6J black nose)
plug 6 is right mixture as shown by mixture ring, but too cold.
The head temperatures are quite high, because measurements were made on a stationary test stand. In a plane, with baffles installed, temperatures drop 20 - 40 degrees.
03-07-2009 | 06:28 PM
#13
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RE: How about this spark plug color?
I agree that from what we can see this looks fine as far as mixture and temperature. However, what to you make of the almost greenish looking deposits on the left hand side of the plug shell? Oil or fuel additive deposits?
AV8TOR
AV8TOR
03-07-2009 | 06:28 PM
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From: Burtchville,
MI
RE: How about this spark plug color?
ORIGINAL: flaminheli
You are correct Ram Jet. To truely read a plug you should be looking way down at the base of the insulater. But the upper portion gives you a general idea of how you mixture is. Just not a true accurate reading. To get an accurate reading you must also accelerate at full throttle, cut the ignition off from full throttle, return the thottle to idle postion and then check the plug. Atleast that is the way I was told to do it from some old sprint car racers.
You are correct Ram Jet. To truely read a plug you should be looking way down at the base of the insulater. But the upper portion gives you a general idea of how you mixture is. Just not a true accurate reading. To get an accurate reading you must also accelerate at full throttle, cut the ignition off from full throttle, return the thottle to idle postion and then check the plug. Atleast that is the way I was told to do it from some old sprint car racers.
You are absolutely correct Sir. Mr. Godon Jennings (my engine tech hero and Guru) would agree too.
Bill
03-07-2009 | 06:33 PM
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From: Burtchville,
MI
RE: How about this spark plug color?
ORIGINAL: Tired Old Man
Little silver balls up at the base could also be the guy running 100LL.....
Little silver balls up at the base could also be the guy running 100LL.....
No problem here, I don't have any.
Bill
03-07-2009 | 06:41 PM
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From: Burtchville,
MI
RE: How about this spark plug color?
ORIGINAL: flaminheli
Piston flakes can also be seen all around the insulater upper portion as shiny, sparkly specs. An indication that you are cooking your engine.
Piston flakes can also be seen all around the insulater upper portion as shiny, sparkly specs. An indication that you are cooking your engine.
Good info. I suppose a person could be running an excessivly cold plug that burned a nice color but it would mask a serious overheating or lean running condition.
Thanks,
Bill
03-07-2009 | 06:47 PM
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From: Burtchville,
MI
RE: How about this spark plug color?
ORIGINAL: pe reivers
This is the final say on plug reading.
I made a nice story of it on my forum, check [link=http://www.prme.nl/forum/viewtopic.php?t=10]here.[/link], or check out TSR racing, who made this chart for reading plugs.
This is a set of plugs I dismantled to show the difference between cold plug and rich mixture.
Plug 1 is slightly lean, as indicated by the head temperature.
plug 2 is slightly richer, the black ring still is not as high as 1/4 isolator length
plug 3 is too rich. The black has crept up to 1/3rd isolator length.
plug 4 is too rich, but heat range is OK (champion DJ7Y)
Plug 5 is too lean (no black ring) It also is too cold (champion DJ6J black nose)
plug 6 is right mixture as shown by mixture ring, but too cold.
The head temperatures are quite high, because measurements were made on a stationary test stand. In a plane, with baffles installed, temperatures drop 20 - 40 degrees.
This is the final say on plug reading.
I made a nice story of it on my forum, check [link=http://www.prme.nl/forum/viewtopic.php?t=10]here.[/link], or check out TSR racing, who made this chart for reading plugs.
This is a set of plugs I dismantled to show the difference between cold plug and rich mixture.
Plug 1 is slightly lean, as indicated by the head temperature.
plug 2 is slightly richer, the black ring still is not as high as 1/4 isolator length
plug 3 is too rich. The black has crept up to 1/3rd isolator length.
plug 4 is too rich, but heat range is OK (champion DJ7Y)
Plug 5 is too lean (no black ring) It also is too cold (champion DJ6J black nose)
plug 6 is right mixture as shown by mixture ring, but too cold.
The head temperatures are quite high, because measurements were made on a stationary test stand. In a plane, with baffles installed, temperatures drop 20 - 40 degrees.
Man, I wish I had this when I was in my 20s and 30s. I did a-lot of engine mods then. At 60 I'm happy if it starts. This is a keeper though.
Thanks,
Bill
03-07-2009 | 06:58 PM
#18
RE: How about this spark plug color?
It looks good to me but without the ability to see further down inside through the use of a coddington magnifier it's really hard to be sure. Looks good from all the outward signs though. Take a look at post #12, Pe has given excellent advice in that one with some very good illustrations.
