The Spark has left my Briggs

[JackSlappy]

I have a Coleman generator with a Briggs & Stratton 10Hp OHV Gen Power 305. The info tags says: 5BSXS 3422HT. The owner’s manual is for models 110000,120000,200000 and 210000. I don’t know the exact model and can’t find anything on the B&S website using 5BSXS 3422HT.

The problem is it won’t start (no spark). The engine has an oil level sensor system that is wired into the On/Off switch which prevents it from running with low oil. I have checked the oil level and it is fine. For troubleshooting purposes I would like to disable the On/Off switch and oil sensor to see if it is that or the ignition. I know the switch and sensor grounds the ignition but am confused on how the On/Off switch is wired. On the back of the switch are three terminals. The middle one goes into the engine front cover, I assume it goes to the ignition. The Off side goes to the oil level system (from the switch the wire runs to a small electrical cube from the cube a wire runs to a oil level sensor in the engine). The On side of the switch runs to ground. This seems a little backwards to me.

I disconnected the middle wire from the switch thinking that it would take the ignition out of the switch but still no spark. I have not been able to find any info on this set up nor any wiring diagrams or troubleshooting tips. Anyone have experience with this or know of a website, etc.. that would help.

A little background: I bought the generator 3 years ago. I start it about 4 times a year and let it run for about an hour. It has always started on the second pull and has always run smooth.

Thanks
jack

 

[javacontour]

Use a multimeter to see what the switches do. If they have connectivity in one position, they should break contact in the other. If there is no change, then the switch is suspect.

I.E. if the run switch is closed in the run position (would show as a continuous circuit in the continuity test mode of a multi-meter) it would be open when moved to the other position.

Or vice-versa.

Likewise for the oil safety switch. Either is easily by passed to see if they are the source of the problem and can be tested in the open and closed configurations for testing.

There are only 4 combinations of 2 switches, both open, both closed, switch A open, switch B closed, switch B open, switch A closed.

If you suspect a switch, it shouldn't take too long to isolate which one.

The run/kill switch is the easiest to test with a multi meter. The other is likely more difficult.

Since there are so few combos, you should be able to try all four permutations in little time.

 

[moklock]

Disconnecting the wire from under the engine shroud and keeping it ungrounded would be the same as an ignition "on" position, so you will likely have to pull the shroud and check the airgap/magnet/coil.

 

[JackSlappy]

Javacontour, Moklock

Thanks for the help. I checked out the switch and the air gap on the coil. Both seem to be OK. I'm now going to move onto checking the coil and ignition. Any advice.

Thanks
jack

 

[greenaccord02]

Just to make sure - check to make sure the spark plug connector wire hasn't come loose or broken away from the little metal clip that fits over the end of the spark plug. Had this happen with a unit of mine and it just about drove me nuts. Also, the wire may be broken within it's insulation. To test, you can stick a sewing needle through the insulator and in contact with the wire, near to the point where it emerges from the coil. Put one hand on the needle and turn the engine over slowly. If you get shocked, then you've got a break in the wire. If not, you may need a new coil all together.

 

[JackSlappy]

Thanks greenaccord02. I think I'll have my wife hold the needle.

jack

 

[greenaccord02]

As long as you pull gently there shouldn't be a problem. Don't pull like you're trying to start it, though. You really will get shocked.