1650 backfired then died

[80zfreak]

I just bought a 1650 a few weeks ago as a backup for my 782. It ran great until I decided to mow with it today. I have two acres to mow and I was mowing with the 1650 for about 20 minutes and it was running and cutting great. Then it started backfiring and died, I let it sit for a few minutes while I picked up a few sticks and it started up and I drove it up to the garage. I checked the gas and the oil both were full so I went out to mow with it some more. I ran it another 20 minutes and it ran great, then it started backfiring again and died. I went to start it again and nothing, not a click, not a sound, nothing. both the 1650 and the 782 have brand new batteries in them but I thought it still might be the battery so I took the one out of the 782 and tried it in the 1650 and still nothing. So my wife towed me back to the house with the 782 and I finished up with the trusty 782 after changing the blades quick in the deck. So what should I be looking at with these symptoms?

[bignastyGS]

Or the points finally gave out...Did you have the PTO engaged? Sounds like since it wont do anything,that may be the trouble. I would try taking a jumper wire and seeing if you can jup the terminals on the starter to see if it turns over. If it does,then you may have a switch trouble or maybe a loose connection..

[Rhoderman]

Battery wire to the key switch, or key switch itself failed?

That's one thing that's common with the supply to the coil, and the supply to the start circuit.

Oh, one other thing that's common between the two circuits - GROUND. Check that first.

[cub1200puller]

Just a week ago on my 1650 while my wife was mowing with it I heard something that sounded like gun shots. It was so bad my nieghbor thaught I was target practicing. Come to find out the bolt that holds the condensor on came out and ungrounded it. Every time it made contact with the engine it wuld back fire then die.

[truckntran]

What happened when you tried to start it immediately after it died? Did it act like compression was lost ?? Could be sticking valves as well as an electrical issue.. Or even vapor lock from boiling fuel if the motor was running way too hot.

Might want to check timing and fuel mixture settings while you are at it. Also if you don't have the tin around teh muffler and you are running side covers it can get too hot....Ideally both muffler box and side covers need to be installed to keep temperatures down...altho some of us aren't entirely certain about those side covers..

Just noticed you say it won't do anything on the restart... My 1200 does the same thing once in a while and wiggling connections at the ignition switch and brake pedal safety switch and sometimes the battery even will get it going. Might want to clean those connections up a little....

[80zfreak]

The first time it died it started right back up and ran good. The second time it died it wouldn't do anything, just dead. both times it died the mower deck was running.

[truckntran]

Give cleaning and tightening connections a try.. along with what I said above, the PTO switch seemed to be involved as well on mine. (You do know it won't start with the PTO turned on, right? It took me a while to figure that one out...a definite Homer Simpson moment for me...)

[thenrie]

Always start with the easiest/cheapest things first. Check your electrical connections. Make sure there are no shorts, loose connections, cracked wires grounding out, or loose mounting bolts, anywhere in the ignition portion of your electrical system. Then move to the points/timing. Make sure they are set properly. Next would be fuel system - fuel lines, filter, carb (if it runs with starter fluid sprayed in the carb, but not without, it is a fuel delivery problem). Then move on to the valves and internals.

With your description, I'm betting you find the problem either in an electrical connection or in the points.

Good luck.

[denrocks1]

It sounds like you killed the spark plug.