Antique Engines and Old Iron
[Home] - [HELP] - [Forums] - [Library] - [Photo Gallery] - [Groups] - [Classified Ads] - [Subscribe] - [Links] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Antique Engine Community > Magnetos, Ignition Coils and Spark Plugs
Forgot Password? Join Us!

Notices

Magnetos, Ignition Coils and Spark Plugs Discussion about magnetos, buzz coils, spark plugs, ignitors and low tension coils.

Magnetos, Ignition Coils and Spark Plugs

Continental AU85 no Spark...


this thread has 5 replies and has been viewed 616 times

Reply
 
Thread Tools Display Modes
  #1  
Old 05-04-2018, 01:45:59 PM
oldmotorette oldmotorette is offline
Registered
 
Join Date: Jul 2016
Location: Crystal Lake, Illinois
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Default Continental AU85 no Spark...

I have new condenser. New points. New spark plug.
The engine started and ran yesterday. Idled well and revved just fine.
Ran it for 10 minutes or so, then shut it down.
A few hours later, it wouldn't start. Not a pop.
Checked for spark. Zero.
Pulled the flywheel, checked for continuity in spark plug wire. It's fine.
Where would I look next?
Coil?
Any way a low-skills guy could test it?
If needed - any idea where to get a replacement?
Thanks!
Reply With Quote
Sponsored Links
  #2  
Old 05-04-2018, 10:14:12 PM
s100 s100 is offline
Registered-II
 
Join Date: Jan 2008
Location: Detroit, Michigan, USA
Posts: 813
Thanks: 197
Thanked 478 Times in 328 Posts
Default Re: Continental AU85 no spark...

Does this one have the points/governor under a little cover on the crankcase of the engine? I would start with things that are most likely to cause problems. With ignition systems the first stop is the points, condenser and related stuff. Yes, they are new. but maybe you got distracted and left a screw loose, maybe a wire is shorting against some metal, maybe some dirt got in the contacts, or maybe the condenser is plain old bad. Try the old one to see if that helps. If you have a new plug handy try that. Also check the plug wire CAREFULLY. I have had several engines over the years that would run or not run with nothing seeming to change, completely at random. Every such instance was caused by a spark plug wire with cracked insulation that, when pressed together or at some distance from metal would work fine but as soon as the crack opened and/or the wire moved closer to metal, out went the lights. Next check the magnets. They should pull strongly at a screwdriver or hacksaw blade. If all of that stuff is good then you can try checking the coil. Can't say for sure but if you put an ohmmeter on the primary side (between the wire going from the coil to the points and ground) I would expect to see something less than 10 ohms. The secondary side (plug wire to ground should be several thousand ohms.
Reply With Quote
  #3  
Old 05-04-2018, 10:23:32 PM
Butch Yowell's Avatar
Butch Yowell Butch Yowell is offline
Subscriber
 
Join Date: Dec 2008
Location: Burke, Virginia, USA
Posts: 245
Thanks: 100
Thanked 147 Times in 82 Posts
Default Re: Continental AU85 no spark...

Check the point setting.
__________________




Butch Yowell
Reply With Quote
  #4  
Old 05-04-2018, 10:28:27 PM
oldmotorette oldmotorette is offline
Registered
 
Join Date: Jul 2016
Location: Crystal Lake, Illinois
Posts: 30
Thanks: 0
Thanked 0 Times in 0 Posts
Default Re: Continental AU85 no spark...

Thanks! I'll try it all - and report back.
Reply With Quote
  #5  
Old 05-09-2018, 03:09:22 AM
cobbadog cobbadog is offline
Registered-III
 
Join Date: Aug 2009
Location: Coopernook. N.S.W. Australia
Posts: 1,378
Thanks: 2,670
Thanked 579 Times in 405 Posts
Default Re: Continental AU85 no Spark...

I always start with a new spark plug and a testing of that. Always run a wire HT lead from magnetos as carbon ones break down all too quickly. A possible problem was that the coil failed once it got hot. A multimeter that can read both ohms and capacitance is best to get answers on condition of coils and condensors. I have been using film capacitors instead of condensors and find them more reliable. Always as suggested clean and adjust your points. It is important they are spotlessly clean and adjusted correctly. Good luck with your trouble shooting and let us know how you get on.
Reply With Quote
  #6  
Old 06-22-2018, 02:08:39 PM
Andrew Mackey Andrew Mackey is online now
Sponsor
 
Join Date: Nov 2004
Location: Rockaway, New Jersey USA
Posts: 13,338
Thanks: 1,865
Thanked 6,107 Times in 3,969 Posts
Default Re: Continental AU85 no Spark...

An old trick at a shop I used to work for was this: Remove the spark plug and ground the base. Put it where you can see if spark occurs. Remove the flywheel and or magnet assembly. Open the points. Take a 9 volt radio battery and ground one side. Take a wire and quickly touch and then remove from the coil wiring, where it meets the points. You should see virtually no spark when you touch the wire to the coil wiring, and when you break the battery connection, a spark at the plug.

If you get a flash at the wire connection, you either have a grounded wire, a bad coil, or bad condenser Check your connections for a grounding fault first. A stray wire that causes a short, misplaced isolation washers, etc. make sure your points gap is right and that the points are opening and closing. Sometimes the points pushrod (plunger) can stick, especially if the engine was sitting a while. If your engine has the points under the flywheel, again check connections and that the points are opening and closing. try running a white business card thru the points. If it comes out grey or oily, they are dirty.
Reply With Quote
The Following User Says Thank You to Andrew Mackey For This Post:
Reply

Bookmarks


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

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
No spark-Continental AU85 3HP cheeshead Magnetos, Ignition Coils and Spark Plugs 4 02-13-2013 07:24:44 PM
Can this Continental AU85 be saved? dw1973 Small Air Cooled Gasoline Engines 9 05-20-2012 10:54:07 AM
Continental AU85 Military j ridings Small Air Cooled Gasoline Engines 1 04-11-2011 09:14:00 PM
Continental AU85 aircoolengine Small Air Cooled Gasoline Engines 7 03-19-2011 06:42:06 PM
No Spark Continental AU85 Jim Cobb Small Air Cooled Gasoline Engines 9 04-21-2009 12:45:53 AM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 03:29:36 PM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2016 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277