shop-talk
[Top] [All Lists]

Re: [Shop-talk] B&S mower engine, surging and dying. Ideas?

To: shop-talk@autox.team.net
Subject: Re: [Shop-talk] B&S mower engine, surging and dying. Ideas?
From: Bob Spidell via Shop-talk <shop-talk@autox.team.net>
Date: Mon, 20 May 2019 21:25:09 -0700
Delivered-to: mharc@autox.team.net
Delivered-to: shop-talk@autox.team.net
References: <alpine.BSF.2.20.16.1905201741220.97678@www570.pair.com> <D80DA500-8AF3-4FD0-8D4F-07D1B2F638E3@icloud.com> <CAK73_u5nanVpqLCZrK0UQGus2wZcyxHisYXBUvE_9_7mZcqzfg@mail.gmail.com> <844aaa2e-1e86-c94c-8c9f-f8ab94c17855@comcast.net>
User-agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.6.1
This is a multi-part message in MIME format.
--===============8259852815168755318==
 boundary="------------C2977EE04CA27F15222B9E8C"
Content-Language: en-US

This is a multi-part message in MIME format.
--------------C2977EE04CA27F15222B9E8C
Content-Transfer-Encoding: 8bit

Addendum:  I'm beginning to think this might be a characteristic of 
air-cooled engines (air-cooled engines have larger clearances to begin 
with).  I've never seen/heard a liquid-cooled engine do exactly this 
but, then again, I don't recall any aircraft engines doing it--they have 
dual ignition systems, maybe that makes a difference?--and, if one did, 
I wouldn't fly behind it.

Bob


On 5/20/2019 8:54 PM, Bob Spidell via Shop-talk wrote:
>
> I had a surging problem on an ExMark--really, a tarted-up 
> Toro--zero-turn and they ended up replacing the engine due to worn 
> rings (intake manifold was getting oiled-up).  Don't ask me why, but 
> nothing else--carburetion, spark, etc.--made sense either.  We're 
> talking a rhythmic pulsing, and not sputtering, right?  Worn rings 
> might make the engine's power ebb-and-flow, I suppose.
>
> Bob
>
> On 5/20/2019 8:48 PM, Scott Hall via Shop-talk wrote:
>> This. Sounds like it's running just long enough to get a vacuum on 
>> the fuel tank, then starving for gas. Then sitting until the tank 
>> reaches atmospheric again. Then repeat.
>>
>> On Mon, May 20, 2019, 7:43 PM Pat Horne via Shop-talk 
>>
>>     Try leaving the fuel cap loose to see if that helps.
>>
>>     Will it start up when it dies with starting fluid.
>>
>>     Peace,
>>     Pat
>>
>>     Pat Horne
>>     We support Habitat for Humanity
>>
>>
>>     On May 20, 2019, at 4:57 PM, David Hillman via Shop-talk
>>
>>
>>       Ok, I'm out of ideas.  Requesting new ones.
>>
>>       I have a Craftsman walk-behind mower with a 163cc Briggs &
>>     Stratton 4-stroke engine ( engine: 104m02-0008-f1 to be precise
>>     ).  It's only 3 or 4 years old, but it will not run.  And it's
>>     starting to piss me off.
>>
>>       It starts normally ( no manual prime or choke, so it takes ~3
>>     pulls but it always has ), and runs fine for less than 5
>>     minutes.  After that, it surges rhythmically and after a minute
>>     or so of that, dies.  Following that, it will not re-start until
>>     allowed to rest for a few minutes.
>>
>>       I have installed a new plug, new air filter, new carburetor,
>>     and new ignitor.  I checked and set the gap on the plug and the
>>     ignitor to spec ( .030" and .006-.014" respectively ).  Has clean
>>     oil, and brand new gas. Fuel screen in the tank is clean, as is
>>     the fuel hose to the carb. Carb bowl has fuel.
>>
>>       What else can be wrong with it?  It seems to be heat-related,
>>     but it has no cooling system.
>>
>>       Thanks.
>>
>>     Obligatory Shop Content: I can't work on anything interesting
>>     until this damn mower runs.
>>
>>
>> _______________________________________________
>>
>> Shop-talk@autox.team.net
>> Donate:http://www.team.net/donate.html
>> Suggested annual donation  $12.96
>> Archive:http://www.team.net/pipermail/shop-talk  
>> http://autox.team.net/archive
>>
>> Unsubscribe/Manage:http://autox.team.net/mailman/options/shop-talk/bspidell@comcast.net
>>
>
> _______________________________________________
>
> Shop-talk@autox.team.net
> Donate: http://www.team.net/donate.html
> Suggested annual donation  $12.96
> Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archive
>
> Unsubscribe/Manage: 
> http://autox.team.net/mailman/options/shop-talk/bspidell@comcast.net
>

--------------C2977EE04CA27F15222B9E8C
Content-Transfer-Encoding: 8bit

<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  </head>
  <body text="#000000" bgcolor="#FFFFFF">
    <p>Addendum:  I'm beginning to think this might be a characteristic
      of air-cooled engines (air-cooled engines have larger clearances
      to begin with).  I've never seen/heard a liquid-cooled engine do
      exactly this but, then again, I don't recall any aircraft engines
      doing it--they have dual ignition systems, maybe that makes a
      difference?--and, if one did, I wouldn't fly behind it.</p>
    <p>Bob<br>
    </p>
    <p><br>
    </p>
    <div class="moz-cite-prefix">On 5/20/2019 8:54 PM, Bob Spidell via
      Shop-talk wrote:<br>
    </div>
    <blockquote type="cite"
      cite="mid:844aaa2e-1e86-c94c-8c9f-f8ab94c17855@comcast.net">
      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
      <p>I had a surging problem on an ExMark--really, a tarted-up
        Toro--zero-turn and they ended up replacing the engine due to
        worn rings (intake manifold was getting oiled-up).  Don't ask me
        why, but nothing else--carburetion, spark, etc.--made sense
        either.  We're talking a rhythmic pulsing, and not sputtering,
        right?  Worn rings might make the engine's power ebb-and-flow, I
        suppose.</p>
      <p>Bob<br>
      </p>
      <div class="moz-cite-prefix">On 5/20/2019 8:48 PM, Scott Hall via
        Shop-talk wrote:<br>
      </div>
      <blockquote type="cite"
cite="mid:CAK73_u5nanVpqLCZrK0UQGus2wZcyxHisYXBUvE_9_7mZcqzfg@mail.gmail.com">
        <meta http-equiv="content-type" content="text/html;
          charset=UTF-8">
        <div dir="auto">
          <div>This. Sounds like it's running just long enough to get a
            vacuum on the fuel tank, then starving for gas. Then sitting
            until the tank reaches atmospheric again. Then repeat.<br>
            <br>
            <div class="gmail_quote">
              <div dir="ltr" class="gmail_attr">On Mon, May 20, 2019,
                7:43 PM Pat Horne via Shop-talk &lt;<a
                  href="mailto:shop-talk@autox.team.net";
                  moz-do-not-send="true">shop-talk@autox.team.net</a>&gt;
                wrote:<br>
              </div>
              <blockquote class="gmail_quote" style="margin:0 0 0
                .8ex;border-left:1px #ccc solid;padding-left:1ex">Try
                leaving the fuel cap loose to see if that helps. <br>
                <br>
                Will it start up when it dies with starting fluid. <br>
                <br>
                Peace,<br>
                Pat<br>
                <br>
                Pat Horne <br>
                We support Habitat for Humanity<br>
                <br>
                <br>
                On May 20, 2019, at 4:57 PM, David Hillman via Shop-talk
                &lt;<a href="mailto:shop-talk@autox.team.net";
                  target="_blank" rel="noreferrer"
                  moz-do-not-send="true">shop-talk@autox.team.net</a>&gt;
                wrote:<br>
                <br>
                <br>
                  Ok, I'm out of ideas.  Requesting new ones.<br>
                <br>
                  I have a Craftsman walk-behind mower with a 163cc
                Briggs &amp; Stratton 4-stroke engine ( engine:
                104m02-0008-f1 to be precise ).  It's only 3 or 4 years
                old, but it will not run.  And it's starting to piss me
                off.<br>
                <br>
                  It starts normally ( no manual prime or choke, so it
                takes ~3 pulls but it always has ), and runs fine for
                less than 5 minutes.  After that, it surges rhythmically
                and after a minute or so of that, dies.  Following that,
                it will not re-start until allowed to rest for a few
                minutes.<br>
                <br>
                  I have installed a new plug, new air filter, new
                carburetor, and new ignitor.  I checked and set the gap
                on the plug and the ignitor to spec ( .030" and
                .006-.014" respectively ).  Has clean oil, and brand new
                gas. Fuel screen in the tank is clean, as is the fuel
                hose to the carb. Carb bowl has fuel.<br>
                <br>
                  What else can be wrong with it?  It seems to be
                heat-related, but it has no cooling system.<br>
                <br>
                  Thanks.<br>
                <br>
                Obligatory Shop Content: I can't work on anything
                interesting until this damn mower runs.<br>
              </blockquote>
            </div>
          </div>
        </div>
        <br>
        <fieldset class="mimeAttachmentHeader"></fieldset>
        <pre class="moz-quote-pre" 
wrap="">_______________________________________________

<a class="moz-txt-link-abbreviated" href="mailto:Shop-talk@autox.team.net"; 
moz-do-not-send="true">Shop-talk@autox.team.net</a>
Archive: <a class="moz-txt-link-freetext" 
href="http://www.team.net/pipermail/shop-talk"; 
moz-do-not-send="true">http://www.team.net/pipermail/shop-talk</a> <a 
class="moz-txt-link-freetext" href="http://autox.team.net/archive"; 
moz-do-not-send="true">http://autox.team.net/archive</a>


</pre>
      </blockquote>
      <br>
      <fieldset class="mimeAttachmentHeader"></fieldset>
      <pre class="moz-quote-pre" 
wrap="">_______________________________________________

<a class="moz-txt-link-abbreviated" 
href="mailto:Shop-talk@autox.team.net";>Shop-talk@autox.team.net</a>
Archive: <a class="moz-txt-link-freetext" 
href="http://www.team.net/pipermail/shop-talk";>http://www.team.net/pipermail/shop-talk</a>
 <a class="moz-txt-link-freetext" 
href="http://autox.team.net/archive";>http://autox.team.net/archive</a>


</pre>
    </blockquote>
  </body>
</html>

--------------C2977EE04CA27F15222B9E8C--

--===============8259852815168755318==
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

_______________________________________________

Shop-talk@autox.team.net
Archive: http://www.team.net/pipermail/shop-talk http://autox.team.net/archive



--===============8259852815168755318==--

<Prev in Thread] Current Thread [Next in Thread>