Sick Big Ten

[BJennings 0]

My son was driving the Big Ten around picking up brush the other day and it was running fine. It started to rain so I went to move it in the shed. It suddenly won't start. It tries to fire, but there is a hollow popping sound coming out of the exhaust. I pulled the head to see if the valves and piston look fine which they do. It almost sounds like a backfire. Could it be timing? It's been close to 15 years since I have been in that motor. What runs the cam/timing?

[Ryan 0]

My B-110 did the samething once. The camshaft lobe that the points rod runs on was worn so bad that it was not allowing the points to open and close all the way. Cam/crank timing are a gear set. Your cam or crank would have had to break if the cam timing is out. Your points, condensor, or ignition may just be wet. Check the kill switch wire first on the points cover to make sure it is not grounding out. If it is not. Check to see if the points are sparking and opening up all the way. This should get you started. Let me know what you find out and we will go from there.

[gjh 0]

I have had a bad condenser cause "popping" and backfiring, with little or no running.

[Woodydel 0]

To me it sounds like a timing problem..Woody

[HubbardRA 20]

I'd also replace the condenser. I have had them become intermittent and sporadic, causing firing at the wrong times. I'd do both points and condenser first before going too much farther. I'd also check for shorting in the wiring, especiaqlly the ignition kill wire. Rod H.