Half an engine is no fun!

Half an engine is no fun!

Post by Joe Pete » Fri, 07 Apr 2000 04:00:00


Like many, my sled is a twin.  Feeding each cylinder is it's very own
carburetor.  (Dual carbed).  One night the tempature was very cold.
(we're talking 20 below).  The next morning I started it up (after about
90 pulls).  It had a top speed of about 30mph.  I knew it was running on
one cylinder.  What I'm asking is why do people always assume that it's
the carburetor thats frozen?  Gas can freeze in the lines too!  When I
knew that engine heat wasn't going it thaw anything out I changed the
spark plugs.  That was it!  Whats going on here?  The plugs were fine
because I changed them only a day ago and it was running fine.  Any
suggestions?

-100% Joe

 
 
 

Half an engine is no fun!

Post by wverno » Fri, 07 Apr 2000 04:00:00

Quote:

> Like many, my sled is a twin.  Feeding each cylinder is it's very own
> carburetor.  (Dual carbed).  One night the tempature was very cold.
> (we're talking 20 below).  The next morning I started it up (after about
> 90 pulls).  It had a top speed of about 30mph.  I knew it was running on
> one cylinder.  What I'm asking is why do people always assume that it's
> the carburetor thats frozen?  Gas can freeze in the lines too!  When I
> knew that engine heat wasn't going it thaw anything out I changed the
> spark plugs.  That was it!  Whats going on here?  The plugs were fine
> because I changed them only a day ago and it was running fine.  Any
> suggestions?

> -100% Joe

Plugs foul, you never know when.  If you're running on 1 cylinder it's
the first thing you check.

 
 
 

Half an engine is no fun!

Post by Michael Har » Fri, 07 Apr 2000 04:00:00

Maybe if gas is flooding the crankcase through the pump diaphragm that could
mean a quick foul come morning. Lots of pulls because the impulse line was
probably filled meaning no/low fuel pressure.

A small hole in the diaphragm may not be noticable in normal running. Except
one plug may foul more frequently. A larger hole could mean real fouling
problems or even burndown on the opposite cylinder as fuel pressure can't be
maintained.


Quote:
> Like many, my sled is a twin.  Feeding each cylinder is it's very own
> carburetor.  (Dual carbed).  One night the tempature was very cold.
> (we're talking 20 below).  The next morning I started it up (after about
> 90 pulls).  It had a top speed of about 30mph.  I knew it was running on
> one cylinder.  What I'm asking is why do people always assume that it's
> the carburetor thats frozen?  Gas can freeze in the lines too!  When I
> knew that engine heat wasn't going it thaw anything out I changed the
> spark plugs.  That was it!  Whats going on here?  The plugs were fine
> because I changed them only a day ago and it was running fine.  Any
> suggestions?

> -100% Joe


 
 
 

Half an engine is no fun!

Post by at » Wed, 12 Apr 2000 04:00:00



Quote:
> Like many, my sled is a twin.  Feeding each cylinder is it's very own
> carburetor.  (Dual carbed).  One night the tempature was very cold.
> (we're talking 20 below).  The next morning I started it up (after about
> 90 pulls).  It had a top speed of about 30mph.  I knew it was running on
> one cylinder.  What I'm asking is why do people always assume that it's
> the carburetor thats frozen?  Gas can freeze in the lines too!  When I
> knew that engine heat wasn't going it thaw anything out I changed the
> spark plugs.  That was it!  Whats going on here?  The plugs were fine
> because I changed them only a day ago and it was running fine.  Any
> suggestions?

> -100% Joe

Never had real gas freeze, even at -45C. Spark plugs do cause
problems, even when they are new.
******************************
From the PC of Doug Bissett
doug.bissett at attglobal.net

******************************
 
 
 

Half an engine is no fun!

Post by David Courtne » Wed, 12 Apr 2000 04:00:00

    This happens in cars all the time... but, you've got more plugs to get
you started.  (Even fuel injected cars will idle rough when started in
super-cold weather... not all the plugs are firing.)
    When you crank the very cold motor over, you draw relatively moist air
(compared to the air that was in the hot cylinder when you shut the engine
down last) into the cylinder.  The moisture condenses on everything "cold"
in the cylinder... including the tip of the spark plug.
    If you look really closely at the tip of the plug... you can see the
"shine" from a very thin coat of ice... that shorts out the plug and
prevents it from firing.
    Usually, you can warm up the plug with a Bic lighter or spray if off
with warm WD-40 to get it to fire.  Although, if you can keep it idling, the
heat from the rest of the engine will usually thaw the plug out within a
minute or so.