Trick plug (Stretching the coil)
05-17-2005 | 05:23 PM
#1
Trick plug (Stretching the coil)
Another thing to try if it's dying rich is to reach into the plug and pull the coil up out of the cavity about half a mm or so. It will make the plug stay hotter at idle.
The above quote is from a well known 4 stroke engine authority in the USA. It came from another forum here on RCU.
It is something I would not have dared do in the past? Maybe I need to loosen up a little?
Have any of you ever done this?
Maybe this explains the need for a new plug at times when the old one still glows?
Enjoy,
Jim
05-17-2005 | 08:16 PM
#2
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From: Mary Esther, Florida, FL
RE: Trick plug (Stretching the coil)
Jim:
Old trick. Used to do it in control line days to extend the life of a plug. Sometimes also we'd reach in to straighten the coil when it had collapsed.
Bill.
Old trick. Used to do it in control line days to extend the life of a plug. Sometimes also we'd reach in to straighten the coil when it had collapsed.
Bill.
05-17-2005 | 08:25 PM
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From: RCHill,
NJ
RE: Trick plug (Stretching the coil)
Maybe this explains the need for a new plug at times when the old one still glows?
Ill try this pull the coil thing with an very used and abused OS 8 plug I have.
05-17-2005 | 08:30 PM
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From: Mary Esther, Florida, FL
RE: Trick plug (Stretching the coil)
All:
Be very careful doing this. If it's an old plug the coil could be brittle, and break off while running. This tends to chip port edges when it gets caught going out.
Bill.
Be very careful doing this. If it's an old plug the coil could be brittle, and break off while running. This tends to chip port edges when it gets caught going out.
Bill.
05-17-2005 | 08:40 PM
#5
RE: Trick plug (Stretching the coil)
ORIGINAL: RC-FIEND
This is what rattles my brain. I experienced this on Saturday, when finishing breaking in my mag .28 . If it glows why in the world won't it ignite the methane ?
Ill try this pull the coil thing with an very used and abused OS 8 plug I have.
This is what rattles my brain. I experienced this on Saturday, when finishing breaking in my mag .28 . If it glows why in the world won't it ignite the methane ?
Ill try this pull the coil thing with an very used and abused OS 8 plug I have.
A plug can be ruined even though it looks ok and still glows. I suspect it has something to do with the coating of the plug wire that acts as a catalist in the methanol-oxygen reaction. If this coating is "damaged" one way or another, your plug is basically ruined. Kinda like running leaded gas in a car that has a catalyct converter... you would be shopping for a new cat very fast.
On the other hand, a plug may look completey wasted, and still function fine. Straightening the wire on such a plug is probably fine. But be careful while you're at it, like WR said.
05-17-2005 | 08:47 PM
#6
RE: Trick plug (Stretching the coil)
Wow, does that ever bring back old memories! As kids we always took a small pin with us and if the plug (the old brass headed KLG's from memory) didn't seem to be working we'd take it out and have a look. Usually the coil would be collapsed so the head of the pin got used to drag it back out. Sometimes the coil would be broken so we'd pull the lower bit up until it tangled with the top part and that gave us a circuit again to get the plug glowing for another flight.Newbies soon learn to use an old plug when running in an engine
05-17-2005 | 09:17 PM
#7
RE: Trick plug (Stretching the coil)
I guess I do remember doing this back in the 50's back behind the high school. Plugs were more fragile then.
Some one mentioned using old plugs to break in a new engine... No truer words were ever spoken.
Enjoy,
Jim
Some one mentioned using old plugs to break in a new engine... No truer words were ever spoken.
Enjoy,
Jim
05-18-2005 | 01:37 AM
#8
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RE: Trick plug (Stretching the coil)
ORIGINAL: downunder
Sometimes the coil would be broken so we'd pull the lower bit up until it tangled with the top part and that gave us a circuit again to get the plug glowing for another flight.
Sometimes the coil would be broken so we'd pull the lower bit up until it tangled with the top part and that gave us a circuit again to get the plug glowing for another flight.
FBD.
