spark 127
 

Hello, need some help here. My 127 looks to have no spark. it was running fine and I cam out to a dead battery the other day. Battery is good had it checked at 2 places and is holding perfect charge connected to tractor now, at 12.8v. I had cleaned all the ground contacts and she spins real fast now. Problem is it does not start.

What I checked and results:
points - gapped at .020 (this is where it was while running i did not change it)
Plug - new autolite 216
I have 12v at the coil in the start and run position
I have 12v at the VR where it should
took plug out connected to wire and held by bolt and no spark.....while cranking

The points and condenser, coil are all less than 6 months old.
While trying to start it, it finally had a HUGE LOUD backfire pop !! sounded like a gun shot.....

I think there is a possibility that I maybe left the key in the run position overnight and thats why the battery was dead? Could this toast the points?

it also has a brand new wireharness and there is no draw.

Help , snow is comming :(

You most likely have one of two conditions.

(A) The secondary side of your Ignition Coil could be gone. Measure between the "tower" (spark plug wire connection) and the negative ( - ) terminals with a DVM and you should be between 8,000 to 12,000 ohms. Also, between the ( + ) and the ( - ) terminals on the coil, you should have about 4 to 6 ohms. If not, replace the ignition coil

(B) Check the Spark Plug Wire. Measure between both ends with a DVM and there should be Zero ohms resistance. If not, replace.

If you inadvertently left the ignition on, it is also possible you got the points hot,
I would look to see that:
# 1 they are not burned and are still @ approx. .020 gap
# 2 insure that they are indeed making contact.
Then I would proceed with the checks that Roland mentioned.
I have seen times when leaving the ign. on, it does burn up the coil.

When cranking the engine without spark occurring @ the plug,
you are loading the engine/muffler with Gasoline.
Then when spark does occur intermittently, ka boom!!! like you describe

Pow
 

i do have the correct gap at the points I checked that first. They look a little discolored but not that bad. I have no draw and battery has good charge. When I had the plug out on the wire and cranked it nothing. When I turned the to the off position it had a little spark that would explain the BAM after it was loaded up with fuel. So when the points are closed they should be touching? I will test the coil and go from there. Might have to pop a new set of points in to check also if everything else checks out.

Yes, points are touching and permitting the current to flow into the coil.
When points close they are building a magnetic field in the coil.
It's when they open, the field collapses causing a spark.
they can look ok and still not have a good contact.
Also I have seen in instances that the switch was left on, and the points became overheated causing the insulated cam rubbing block to melt making them short to ground all the time.
this usually occurs with lesser expensive aftermarket points made with a nylon rubbing block/bushing insulation.
With the ignition on, and the points in the closed position, you should be able to cause a spark @ the spark plug by flicking the points open/closed with your finger nail, you will not receive a shock as you are only dealing with 12 Volts.
But more times as not, the coil is also gone bad from overheating from the ignition being left on, check as Roland said.
lets us know what you find so others learn also.

Fixed.......sort of
 

I decided to take points cover off.......have the plug out and on the heat shield and turn the key nice strong spark at the points and the spark plug......Hmmmm weird. I put the points cover back on........ NO spark !!! take it off......SPARK......... Then I remembered the cover was not all the way snugged up when I took it off............ Looks like the points cover is grounding something out........ The gasket looks a bit compressed, so I will get a new gasket and see if that is the issue....... I also need to change the wire from points to coil, it looks original......does anyone know if this should be a solid wire or stranded? Thanks

Use 14GA Stranded wire.

It looks like you found the problem, probably the wire end is just touching the cover, or the wire is a bit frayed and is getting pinched under the cover.
I’ve seen them frayed @ the grommet, and it is hard to see.
Always remember, a stranded wire tolerates vibration much better than a solid wire.
Glad you found the problem without having the cost of a coil or points.
There is always that good feeling one gets when they solve a problem.:biggrin2.gif:

To fix
 

Well I will make a new wire tonight and fix that up. I was very happy that it started up very fast this AM. with all the grounds cleaned up and good battery charged she cracked on first revolution. I did get a 1/2 hour seat time to clear the driveway this am.