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Re: [Shop-talk] It's A Simple Machine, Right?

To: Jeff Scarbrough <fishplate@gmail.com>
Subject: Re: [Shop-talk] It's A Simple Machine, Right?
From: Doug Braun <doug@dougbraun.com>
Date: Wed, 16 Jul 2025 19:16:01 -0400
Cc: "shop-talk@autox.team.net" <Shop-talk@autox.team.net>
Delivered-to: mharc@autox.team.net
Delivered-to: Shop-talk@autox.team.net
References: <CAO8Q7CO28uMFK_qVdDwZ-OBk=87gcF1_c=qreESced_OnJtt5w@mail.gmail.com> <CAO8Q7CPJEZQ4sFtZZr8w0mTnp4GZMTkQ6ap2tSyPvDO5U8HtuQ@mail.gmail.com> <CAO8Q7CP3u33QjKuQYvgqZioc5EoREja93C=XGjx-NAc4So8RaQ@mail.gmail.com>
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On a similar topic, look at this video of the insides of a cheap Chinese
replacement gas engine.  The camshaft lobes are PLASTIC!
They don't make 'em like they used to...

https://youtu.be/7IKNiQwTaoo?feature=3Dshared&t=3D493

Doug

On Tue, Jul 15, 2025 at 9:02=E2=80=AFPM Jeff Scarbrough <fishplate@gmail.co=
m> wrote:

> Update to the update:
>
> New coil arrived yesterday.  Installed it today - no spark.  Reinstalled
> the old one - weak spark.  Discovered the old one was upside-down -
> inverted it and reinstalled it - no spark.  Disconnected the grounding wi=
re
> - strong spark.  The old one worked with that wire connected, so there's
> another rabbit hole we need to go down for the future.
>
> Meanwhile, now that we had a good spark, we gave it a shot of ether and
> cranked.  It ran, but very low power.   So, not the spark.  Checked
> hte fuel flow at the carb, still adequate.  So my7 thoughts turned to the
> valve train...
>
> Went to take the valve cover off, but it was thoroughly glued on.  So I
> pulled the muffler so I could see the valve stem.  It was going up and
> down, so I pulled the intake and looked way down in the hole.   The valve
> was *not* moving!
>
> At that point, I was confident in prying the valve cover off being a good
> idea.  Turns out the top inch of the intake pushrod was lying in the oil
> drain back to the crankcase.  The pushrod looks like it was getting crimp=
ed
> and finally broke where it was getting necked down.  I've never seen
> anything quite like this.  I'm not sure now how it was running weakly on
> ether or gas if the intake valve didn't open to admit any air or fuel.
>
> More new parts on order.  At least I found something I could verify was
> broken.  I call that progress.
>
>
>
>
>
>

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<div dir=3D"ltr"><div dir=3D"ltr"><div>On a similar topic, look at this vid=
eo of the insides of a cheap Chinese replacement gas engine.=C2=A0 The cams=
haft lobes are PLASTIC!</div><div>They don&#39;t make &#39;em like they use=
d to...</div><div><br></div><div><a href=3D"https://youtu.be/7IKNiQwTaoo?fe=
ature=3Dshared&amp;t=3D493">https://youtu.be/7IKNiQwTaoo?feature=3Dshared&a=
mp;t=3D493</a></div><div><br></div><div>Doug</div></div><br><div class=3D"g=
mail_quote gmail_quote_container"><div dir=3D"ltr" class=3D"gmail_attr">On =
Tue, Jul 15, 2025 at 9:02=E2=80=AFPM Jeff Scarbrough &lt;<a href=3D"mailto:=
fishplate@gmail.com">fishplate@gmail.com</a>&gt; wrote:<br></div><blockquot=
e class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px s=
olid rgb(204,204,204);padding-left:1ex"><div dir=3D"ltr">Update to the=C2=
=A0update:<div><br></div><div>New coil arrived yesterday.=C2=A0 Installed i=
t today - no spark.=C2=A0 Reinstalled the old one - weak spark.=C2=A0 Disco=
vered the old one was upside-down - inverted it and reinstalled it - no spa=
rk.=C2=A0 Disconnected the grounding wire - strong spark.=C2=A0 The old one=
 worked with that wire connected, so there&#39;s another rabbit hole we nee=
d to go down for the future.=C2=A0=C2=A0<br><br>Meanwhile, now that we had =
a good=C2=A0spark, we gave it a shot of ether and cranked.=C2=A0 It ran, bu=
t very low power.=C2=A0 =C2=A0So, not the spark.=C2=A0 Checked hte=C2=A0fue=
l flow at the carb, still adequate.=C2=A0 So my7 thoughts turned to the val=
ve train...</div><div><br></div><div>Went to take the valve cover off, but =
it was thoroughly glued on.=C2=A0 So I pulled the muffler so I could see th=
e valve stem.=C2=A0 It was going up and down, so I pulled the intake and lo=
oked=C2=A0way down in the hole.=C2=A0 =C2=A0The valve was *not* moving!<br>=
<br>At that point, I was confident in prying the valve cover off being a go=
od idea.=C2=A0 Turns out the top inch of the intake pushrod was lying in th=
e oil drain back to the crankcase.=C2=A0 The pushrod looks like it was gett=
ing crimped and finally broke where it was getting necked down.=C2=A0 I&#39=
;ve never seen anything quite like this.=C2=A0 I&#39;m not sure now how it =
was running weakly on ether or gas if the intake valve didn&#39;t open to a=
dmit any air or fuel.<br><br>More new parts on order.=C2=A0 At least I foun=
d something=C2=A0I could verify was broken.=C2=A0 I call that progress.</di=
v><div style=3D"outline:none;padding:10px 0px;width:22px;margin:2px 0px 0px=
"><br></div><br></div><br><br>
<br>
</blockquote></div></div>

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