Small Engines (Lawn Mowers, etc.)/riding mower won`t crank

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QUESTION: I have an older riding mower that will not crank. I had a battery that would not stay charged and could not be opened/filled, so I installed a new battery. Surprisingly, after charging the batter, the mower cranked up (multiple times). I had to repair a tire, so it sat for most of a week. Now it is back to not cranking.

The new battery was (surprisingly) low, according to the charger, so I charged it back up. It will not crank. I replaced the spark plug. No luck.

Should I try replacing the fuel filter next? How do I stop the flow of gas to it while doing that?

The mower is a Cub Cadet HDS-2135, Model No. 136-214-100, Serial No. 334940. It has a Kohler engine.

ANSWER: You can use a c-clamp or vice-grips to stop the fuel flow...not the recommended method but it will work.  There are special tools make to pinch the fuel line to stop the fuel flow but the c-clamp will work.

You you say crank, do you mean the battery will not spin the engine?

If the battery is spinning the engine then you need to verify you have spark.

Let me know if the battery is spinning the engine and if you have spark.
Eric

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QUESTION: The battery makes the engine turn, but it gives no sign that it's trying to fully run (like a spark or fuel problem). Is the best way to check the spark to get an inline spark tester? I`ve been thinking of getting one anyway.

ANSWER: Yes, the inline is the best IMO. I once had a ignition module jump the spark plug gap with the plug out and ground to the engine, it would give you a shock, not a good or fun test, but when I install the inline tester the module did not produce spark.  Bottom line, the module was too weak to fire under compression.

You can rule out the module, without a tester, by dis-connecting the small wire connected to the ignition module.  You can dis-connect it without removing any parts is you find the connection on the engine block, usually near the throttle/governor assembly...it is just one wire.

Keep in mind you can NOT shut off the engine with the small wire dis-connected.  You can either flood the engine by choking it or you can pull the spark plug to shut-off the engine.

Let me know if this helps.
Eric

---------- FOLLOW-UP ----------

QUESTION: It has spark.

Answer
How old is the gas in the fuel tank?  If it is more than 60 days old it should be drained and replaced with new fuel.

Are you familiar with priming an engine to see if it tries to start?

I use an diner style ketchup bottle with the taper tip but you can use a soda bottle with a small hole drilled in the cap.

I put just a little, new fuel, in the bottle, remove the air filter and squirt a little fuel directly into the carburetor.  Do this OUTSIDE and have a fire extinguisher on hand in the event of a fire.  DO NOT fill the primer bottle full of fuel, just use a little as it should not take much to see if the engine tries to start.

Let me know if the engine tries to start by priming.
Eric

Small Engines (Lawn Mowers, etc.)

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Eric A. Jones

Expertise

Lawnmower Repair . Certified Master Service Technician from B&S. Have 23 years experience on B&S, Lawn Chief, Weed Eater, Echo, Peerless, Wheel Horse, Snapper, Atlas, MTD, McCulloch, Homelite and many other numerous brands. Specialize in electrical repair.

Experience

Born and raised in the midwest. Started tinkering with engines when I was about 14 on my Suzuki RM-80. I began lawn mower repair at a small hardware store. I knew absolutely nothing. I read lots of repair manuals and met an older fellow who taught me many lessons. I continued working on small engines through high school and paid my way through college working on mowers at the same hardware store. Decided to get away from the midwest and mower repair so I joined the Air Force. I repaired air traffic control electronic equipment and ended up in Hawaii where I got a part time job at Small Engine Clinic. I gained a lot of experience from the Small Engine Clinic and had a blast repairing small engines. I then took the Briggs and Stratton Master Service Technician test and earned my MST. I then traveled to Wisconsin where I attended the factory update training seminar and received formal training. Continued working on mowers part time as I completed 20 years of military. Retired from the military on a Friday and continued in the lawn and garden industry the next Monday.

Education/Credentials
MAS Aerospace Operations BA Mathematics AAS Electronic Communications AAS Electronic Technology

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