Wont start

[gregnoh]

Hi all....New poster here.  Have a 6V that won't start.  Rolls good, have fire at plugs, getting gas at carb........Any ideas where to start?  Last time I had it running,(3 weeks) it was missing as well.  Help!

Greg

[Pete P.]

Greg --

Not sure what model you have (you say 6v but don't identify the tractor) so I'll assume it's an N of some sort with front mount distributor.  If that's so, it's more than likely an ignition problem -- such problems are the bain of us with front mounts. You say you have spark but it's crucial that it be good, blue and fat sparks -- no weakness whatsoever.  A good place to start (no pun intended) is to take the dist. off, service the points (gap is 0.015 in., 0.018 in. works nice on a worn dist.) and all internal connections, clean cap & rotor, change plugs and clean / replace any wires or terminals that are not 100 %.  Also pay good attention to the primary contacts on the coil (the springy thing on the bottom and the stud on top), the concave screw that the spring contacts, and all wiring, connections, the switch and resistor  -- in other words the whole primary circuit.  Any resistance here will be detrimental in making good spark reliably.

See what that does and let us know.  I'm sure anyone here would be happy to walk you through servicing the ingnition system in more detail if you like.

Pete P.
Harborcreek, Penna.
   

[gregnoh]

Hi Pete,

Thanks for your reply.  Sorry about not ID'ing my tractor.  It is indeed an N........'42 model.  I will check the things you mentioned and post back.  Also, I have a guy coming here next week that is going to check the compression for me. (He has a gauge) I need my old tractor back!!!

Thanks again,

Greg

[Pete P.]

Greg --

Ah, a 2N.  (I'd love to find an authentic wartime model, i.e. magneto, steel wheels, etc., but I digress.) 

Sorry if you or your friend know this but just for completeness -- when you do the compression test remove all plugs and make sure the choke and throttle are wide open.  The shop manual says to do the test hot but it's useful to do one cold first, then heat the engine up and do again hot.  Crank so that the gauge quits moving, at least five or six compression strokes.  A good engine should develop about 100 psi although 80 psi hot is not uncommon.  Each cylinder should give similar readings, say within 20 % of highest reading. 

My guess is that across-the-board lack of compression is not your issue.  Poor compression makes for hard starting, plug fouling and low power, but once the engine runs it runs.  You said last time she ran she missed, that's probably ignition with other less probable causes being a sticky valve (which compression test will indicate) or really bad carburetor adjustment. 

good luck,

Pete P.
Harborcreek, Penna.