Frustrated with a Cub LT 1018 No Start problem

Rookiesmom said:
Fellas help a gal out. Y'all are going to laugh at me. I borrowed my neighbors LT1018 to mow my grass it was a little hard to start but would eventually do so. While mowing the steering bushing broke, from age mostly the engine was running fine. I replaced the bushing and could not get it to start. I checked the voltage on the battery which required charging from about 11.7 volts to 12.3 volts ..no problem doing that. Still would not start so I checked the voltage coming out of the starter solenoid, confirmed that when the key was turned the solenoid was getting power ......no joy ..power went in but solenoid was dead, fuse was good...replaced the soleinoid..confirmed 12 volts out of the hot wire to the starter and it was fine. Still no start. Neighbor bought a new starter and because of the way the starter bolts up to the engine housing (and the fact that I didn't have long torx tools) I took off the flywheel.when the flywheel was pulled the timing key fell out sheared. Replaced the timing key. Note that the timing key, though sheared was still in line with the key way when I pulled it so timing should have been fine. I replaced the starter but though now the engine turned rapidly all I could get out of it was a few weak cough's of trying to run for about 5 seconds then...nothing. Gaps on the coils were in spec. Noticed the breather tube was old and cracked. replaced that. Used starting fluid down the intake and nothing, no start. Went to AI GROK and it suggested checking the valve lash. Looked up the specs and reset the valve lash for both cylinders. Yes I have and used feeler gauges. Both intake and exhaust tolerneces were a little loose. Had high hopes that would do it but NOOOO it still would not start. I took the carberator off and checked the needle valve, used carb cleaner on the emulsion tube and used a maybe 24 gage wire to ream said emulsion tubes, cleaned the bowl and checked to make sure the fuel solenoid was working (it was). Put it all back together and though turning beautifully, it would not start. So, though rapidly losing my hair and mind, I put a new fuel filter on it and replaced a couple of 21 year old fuel lines. Cleaned the fuel pump and the screen on the back side of it. The vaccum tube from the valve cover to the fuel pump was fine...no rot or tears, no obstructions. Checked the fuel cap and made sure the vent holes were still good/present. Pulled the plugs after turning it and they were slightly wet so it was getting fuel. I'm Stuck in quicksand here, I know enough about these small engine to do what I have done but not enough to know what else to do or where I have gone wrong. The engine is a B&S Model 40H777, built about 2004 0r 2005. Any suggestions?
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Have you bypassed the Safety Switches? You have done everything else except replace coils
 
Can I ask have you tried spraying a little starting fluid or other combustible into the air filter area to see if it tries to start if it tries to start probably a fuel issue, if it doesn't try to start on to spark checking. To me your original post was confusing so I want to ask is the engine turn over at all?
 
She said she tried starting fluid in the breather. Before ruling that out, id try a short squirt thru the spark plug hole. If it doesn't pop, your problem is probably electrical.

That can be any of the clutch, seat or other safety switches, any wiring or even the key switch. It could include the timing, the coil, the plug, wires, or anything relating to ignition.

You've practically shot at the engine problems with a blunderbuss, a 17th centry ancestor of the shotgun, kmown for inaccuracy. It's time to focus on only electrical.
 
Rookiesmom said:
Fellas help a gal out. Y'all are going to laugh at me. I borrowed my neighbors LT1018 to mow my grass it was a little hard to start but would eventually do so. While mowing the steering bushing broke, from age mostly the engine was running fine. I replaced the bushing and could not get it to start. I checked the voltage on the battery which required charging from about 11.7 volts to 12.3 volts ..no problem doing that. Still would not start so I checked the voltage coming out of the starter solenoid, confirmed that when the key was turned the solenoid was getting power ......no joy ..power went in but solenoid was dead, fuse was good...replaced the soleinoid..confirmed 12 volts out of the hot wire to the starter and it was fine. Still no start. Neighbor bought a new starter and because of the way the starter bolts up to the engine housing (and the fact that I didn't have long torx tools) I took off the flywheel.when the flywheel was pulled the timing key fell out sheared. Replaced the timing key. Note that the timing key, though sheared was still in line with the key way when I pulled it so timing should have been fine. I replaced the starter but though now the engine turned rapidly all I could get out of it was a few weak cough's of trying to run for about 5 seconds then...nothing. Gaps on the coils were in spec. Noticed the breather tube was old and cracked. replaced that. Used starting fluid down the intake and nothing, no start. Went to AI GROK and it suggested checking the valve lash. Looked up the specs and reset the valve lash for both cylinders. Yes I have and used feeler gauges. Both intake and exhaust tolerneces were a little loose. Had high hopes that would do it but NOOOO it still would not start. I took the carberator off and checked the needle valve, used carb cleaner on the emulsion tube and used a maybe 24 gage wire to ream said emulsion tubes, cleaned the bowl and checked to make sure the fuel solenoid was working (it was). Put it all back together and though turning beautifully, it would not start. So, though rapidly losing my hair and mind, I put a new fuel filter on it and replaced a couple of 21 year old fuel lines. Cleaned the fuel pump and the screen on the back side of it. The vaccum tube from the valve cover to the fuel pump was fine...no rot or tears, no obstructions. Checked the fuel cap and made sure the vent holes were still good/present. Pulled the plugs after turning it and they were slightly wet so it was getting fuel. I'm Stuck in quicksand here, I know enough about these small engine to do what I have done but not enough to know what else to do or where I have gone wrong. The engine is a B&S Model 40H777, built about 2004 0r 2005. Any suggestions?
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My suggestion is clear, you seem to be very knowledgeable about the mower and engine, you have tried everything but the obvious solution. Go inside retrieve your 12 guage shotgun. If you dont own one borrow one. Load it with 3 slugs, empty the gun I to the engine. Set it on fire, and push it off a cliff. THEN GO BUY ANYTHING ELSE BUT A CUB CADET.
 
Use a screw driver handle end, and rap every switch and relay. I think time and moist air has corroded somethign electrical from doing its job. Pray, and then try to get it started again. Oh yeah, check the magneto too, no broken elec.
 
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After about 500 hours on the ignition the coil is suspect. "The Briggs & Stratton 594626 magneto coil (also called an armature-magneto or ignition coil/armature) includes a transistor as part of its solid-state electronic ignition system.". That's a lot of heat and cycles for a coil. And considering this is a twin with lost spark ie, coil fires every revolution, transistor/coil firing events are doubled. For 500 hours at 3300 rpm that's 198,000 firing events, for 500 hours it's 99,000,000 firing events.
 
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Check the spark. Take an old plug open the gap up to about 1/4-inch install the plug wire to the plug. Ground the body of the plug to the engine and spin it over and see if it has spark to jump the gap. If not up plug the kill wire from the ign modules and try again. When she tried to start it using starting fluid that is usually a good sign it has no spark.
 
You need to make absolutely certain the Spark is Hot. Out of starting problems, This is the hardest to find. You need a Real Spark Tester than uses an adjustable Gap. It should jump a Hot Blue Spark from at least 1/4 inch away. If it's yellow, but gets blue when gap is closed, Coil or Gap is bad. Make sure the Flywheel is All the way Down. Key can lift on one side and prevent this. It should Start and run on One Cylinder...Compression is Not the problem...Would not start with Fuel Present...Bad Spark. Good Luck.
 
At this point, believe i would begin looking at the safety switches malfunctioning. Specifically the seat switch which tests good some of the time.

Years ago, I had a seat switch that worked perfectly since new. But there was wear on the plastic switch housing and one day I must have hit a bump in the yard and moved it just slightly.

Worked sometimes and not others (unless I sat on the seat in just the right spot. Bugger to find as it proved good diring testing.)]
 
Let's back up a bit. The initial problem was a steering bushing. I'm assuming the bushing on the end of the steering wheel shaft, correct me if I'm wrong. It ran prior to replacing the bushing but stopped running after bushing replacement, correct? Is there any chance when you replaced the bushing an electrical connector got disconnected and not reconnected? Perhaps if you separated a connector maybe on reconnection a pin got pushed out of the connector and lost contact? What about a pinched wire in that area that is grounding or open? Sometimes electrical issues can be a real nightmare.
 
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