1979 Spitfire 340 fuel Problem??

1979 Spitfire 340 fuel Problem??

Post by Bill Cornel » Thu, 21 Jan 1999 04:00:00


I have a 1979 John Deere Spitifre 340.  My problem is that the sled will
not idle when warmed up.  The carburetor has just been rebuilt
(disassembled, cleaned and returned to stock settings).  I seems to be
lacking fuel pressure at idle warm and has a slight bog on
acceleration.  How do the fuel pumps operate?? how are they tested, and
can they be repaired??  Thanks to all in advance.
 
 
 

1979 Spitfire 340 fuel Problem??

Post by HiJaak79 » Fri, 22 Jan 1999 04:00:00

Hello,
Pumps can be repaired and they opperate off of crankcase pressure.If the pump
was the problem,  it would show up more at high speed.  I believe U may have a
deeper problem with possibly compression or a crankcase air leak.  U may need
to see a snomobile dealer to have these items checked.  Betting on a air leak.

 
 
 

1979 Spitfire 340 fuel Problem??

Post by Jerry Franc » Fri, 22 Jan 1999 04:00:00

Who did the cleaning job?Many times someone unfamiliar with snowmobile or
bike carbs will overlook things.  I'm betting the pilot jet is still dirty,
or the passageway it feeds is obstructed- your symptoms point to this.. have
it opened up again, spray out all the passages with contact cleaner or brake
cleaner, observe the flow of cleaner through the various holes,hold the
pilot jet to a light to make sure it is open.The pilot jet is cheap, replace
if you can't clean it out.  Jerry France
Quote:

>I have a 1979 John Deere Spitifre 340.  My problem is that the sled will
>not idle when warmed up.  The carburetor has just been rebuilt
>(disassembled, cleaned and returned to stock settings).  I seems to be
>lacking fuel pressure at idle warm and has a slight bog on
>acceleration.  How do the fuel pumps operate?? how are they tested, and
>can they be repaired??  Thanks to all in advance.


 
 
 

1979 Spitfire 340 fuel Problem??

Post by Supchri » Tue, 26 Jan 1999 04:00:00

your  fuel pump may be the problem  i don't know how to fix that but it sounds
like you have a hole in the gasline