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B&S model 20 service/technical manual

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Category: General
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URL: http://forums.bajasae.net/forum/forum_posts.asp?TID=17
Printed Date: Nov/30/2021 at 1:33am


Topic: B&S model 20 service/technical manual
Posted By: TerpsRacing-Dan
Subject: B&S model 20 service/technical manual
Date Posted: Nov/14/2008 at 1:18am
Does anyone have one that they would be willing to email to me?  I'd really appreciate it.

We have a fairly new motor that is not getting any spark and for the life of me I can't track it down.   Any ideas?



Replies:
Posted By: jarmumd
Date Posted: Nov/14/2008 at 11:50am
I remember getting a special spark testing tool to help with that - as opposed to holding the spark plug on a ground...  (I've shocked the heck outta myself doing it that way)...
a quick search found this... http://www.mfgsupply.com/m/c/32--9773.html?id=gnfgcz3n

Trouble is...  it's either the spark plug, the wire to the spark plug, the magneto, or the flywheel...  not much to work with...  You might could try making the magneto to flywheel gap smaller and see if that helps... I think that Auburn had a BAD magneto last year - I wonder if Briggs has started to put out a bad batch of them?  Is there anyway you can replace only the magneto (maybe off an old engine) and see if that fixes it?


Posted By: JeremyB
Date Posted: Nov/14/2008 at 12:06pm
Here are some references:

http://www.briggsracing.com/racing_engines/model20/ - Briggs Racing: Model 20 Info
http://www.briggsracing.com/racing_engines/model20/model20_ipl.pdf - Model 20 Parts List
http://www.briggsracing.com/racing_engines/model20/model20_drawings-dimensions.pdf - Model 20 External Drawing
http://www.briggsandstratton.com/pdf/owners_manual/100%5C277040TRI_B-Domestic.pdf - Model 20 Operator's Manual

But you probably already have all of those. I don't think the service manual is available in PDF unless somebody manually scanned them.

The ignition system on the Briggs is pretty simple.
http://faqs.custhelp.com/cgi-bin/faqs.cfg/php/enduser/std_adp.php?p_faqid=3426&p_created=1098407641 - How does the ignition system function?
http://faqs.custhelp.com/cgi-bin/faqs.cfg/php/enduser/std_adp.php?p_faqid=3761 - How does the Magnetron Ignition System function? How can it be tested?

It could possibly be something other than the magneto, such as a faulty spark plug, weak flywheel magnet, missing/damaged flywheel shaft key (flywheel won't spin),


Posted By: TerpsRacing-Dan
Date Posted: Nov/15/2008 at 9:04am
We ended up getting it figured out, it was a bad connection in the armature.

I actually tested spark with a timing light, until I figured out where the fault was. 

I've seen the stuff on their website, we're in the process of rebuilding an old motor that got driven into a swamp Censored , so if anyone has a copy I still could use it.



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