Go Back   RCLargeScale.com > Large Scale General Tech > Electronics



Thread: coil testing

LinkBack Thread Tools Display Modes
Old 02-22-2010, 08:58 AM   #1
Join Date: Dec 2008
Posts: 370
Default coil testing

im surprised no one covered this topic of coil testing.
and what things can make the coil go bad .

i have a zenoah motor ,what resistance should i get on a meter?
were do you place probes at and stuff like that.

it good to use a jumper wire attached to the head to the spark plug to give your self more room.

are their any good after market tester made for this?
Lord shado is offline   Reply With Quote
Sponsored Links
Old 02-22-2010, 09:17 AM   #2
Join Date: Dec 2008
Posts: 370

Actually there are 2 coils in the magneto, a primary coil and a secondary coil. The primary coil can consist of about 100 turns of wire whereas the secondary coil has thousands of turns of hair thin wire. The ends of the primary coil are connected to the tabs on the magneto, and then to the killswitch. One end of the secondary coil is connected to the U shaped metal armature on the coil and the other end goes to the spark plug wire. Since the metal armature of the magneto is screwed directly onto the engine head the high voltage from the spark plug arcs directly to ground and completes the loop.

When the magnet passes by the U shaped armature it induces a current in the primary coil. When that current peaks an internal switch trips that cuts the current flowing through the primary coil. This causes the magnetic field from the primary coil to collapse. That collapsing field then induces a current in the secondary coil and since there are far more turns in the secondary there is a huge increase in voltage. A killswitch bypasses that internal switch and does not allow the field from the primary to collapse and thus no voltage is induced in the secondary and no spark.
Lord shado is offline   Reply With Quote
Old 10-26-2010, 07:42 PM   #3
Join Date: Dec 2008
Posts: 370

i got a new coil how do you attach the spark plug piece?
Lord shado is offline   Reply With Quote

coil testing - Similar Threads
Thread Thread Starter Forum Replies Last Post
Testing! 1CrazyDude Testing 1 2 3 2 02-27-2011 09:43 PM
Ignition Coil fitting delboy Engine & Exhaust 5 06-06-2010 03:47 AM
HPI 5b coil problem? lords Engine & Exhaust 21 11-30-2008 10:25 AM
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

All times are GMT -7. The time now is 04:01 PM.

Powered by vBulletin® Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
Content Relevant URLs by vBSEO ©2011, Crawlability, Inc.
Garage Plus, Vendor Tools vBulletin Plugins by Drive Thru Online, Inc.