C85 backfires and quits after jump starting?

[Mr Sweep 1]

My tractor wouldn't start. So i jump sarted it with my van. I attached cables jumped on tractor and started right up. I detached cables put c85 in gear and a minute later backfires and quits. Checked oil gear oil gas all good. Battery reads 10.8 voltz. repeated this process 4 times to drive c85 back to my garage. Anyone had this before. Oh and its a new battery last year. I looked for a short or loose connection and didn't find anything???

[953 nut 58,065]

        Is this a sudden phenomenon or has it been coming on gradually? Did it run fine last summer then sit all winter and now isn't running right? Is the gas fresh and have you been using gas with ethanol in it? Did you charge the battery and install a new Champion H-10 spark plug gaped at .035"?

[Mr Sweep 1]

I got the mower running last year. The mower sat for years and wasn't running. Landlord said if I got it running I could use it. Beginning last year I cleaned all wire connections, replaced spark plug, drain and replaced gear oil and engine oil and gas and greased all bearings. Oh and new battery. Probably nothing wrong with old battery. Ran great except when I would be going down hill sometimes the problem I described would happen and I had to slid the battery towards me and the mower would start back up. I thought the wire harness on the right side of battery had a short but it looks fine I cleaned the connectors and put it back on and I charged the battery to a reading of 12.4 last knight and same problem. Thanks for responding by the way. 

[pfrederi 18,356]

You said you moved the battery...can it slide around in its holder?? If so one of the terminals may be hitting something shorting it out.  The drop in system voltage may kill your spark

[Mr Sweep 1]

I wired battery in place so it would stop sliding. Last year but problem persisted. So then I gently would pull the wire harness towards me while turning the key and the engine would start. But its not working for me this year. And thank you for responding.

I wired battery in place so it would stop sliding. Last year but problem persisted. So then I gently would pull the wire harness towards me while turning the key and the engine would start. But its not working for me this year. And thank you for responding.

P.S. when I jumped the battery yesterday I would not need to touch anything I just turn the key and it started right up. Maybe if the battery isn't fully charged it Doesn't have the power to engage the starter?

[pfrederi 18,356]

10.8 volts is way low.  If you can sometimes fix it by pulling on eh harness you have a connection issue some where.  12.6 is a fully charged battery

[Mr Sweep 1]

Just cut the grass no problems. But I charged battery up to 12.4. When finished battery read 12.0. How does the mower charge the battery?

[pfrederi 18,356]

Charging stator coil produces 30 Volts (+/-) AC volts (under the flywheel)  Voltage regulator converts that to DC about 14 volts to charge battery.  What is voltage while you machine is running?  Should be 13.6 to 14,6vDC

[Mr Sweep 1]

With engine running the battery voltage is 12.3.

11.8 to 12.3

[953 nut 58,065]

Have you measured the AC Voltage between the two wires on the regulator coming from the engine?

[Mr Sweep 1]

OOps. Lost power in storm. Then forgot battery was charging now reads 14.0 after removing charger.Do I test the regulator with engine running?

 

[pfrederi 18,356]

Disconnect the plug from the regulator.  Use your multimeter on AC put the probes in the the two white wire terminals. Run the engines at at least 2/3rd throttle you should get a reading over 30 volts AC.

[Mr Sweep 1]

36 voltz

 

[pfrederi 18,356]

If that is so then your problem is downstream, most likely the regulator itself.  Make sure all you connections are clean an secure and the orange wire (most likely orange) from the regulator goes to the r terminal on your ignition switch.

 

As said before make sure your regulator case is well grounded.  if you still do not have at least 13.6v with teh engine running then time for a new regulator.

[Mr Sweep 1]

Ok,

Thank You

[pfrederi 18,356]

one other more remote possibility...if your ignition switch is faulty.  Check and make sure there is continuity between the R terminal and  B terminal when switch is in run position.

[Mr Sweep 1]

will do thanks