2011 21.1 Ask Albert!

Dear Albert,
I climbed into my tractor the other day and, much to my dismay, when I turned the key on, it would not start. The engine does not turn over or there is a clicking sound. Where do I start and how do I figure out what is going on?
Sincerely, Trying to Get My Tractor Going

Dear Trying,
When a vehicle won’t start because the engine won’t crank over, the condition of—and the connection between —the battery, solenoid, starter, and wiring to the ignition need to be evaluated for their functionality and connections. Pull and clean all connections, inspect wires, etc. and replace anything worn or cracked.

I might put in here that you need to make sure your battery is up and holding a healthy charge. A multimeter might say you have 12 volts, but a load tester will tell you if you have a real substantial charge available. There are small electronic models now available.

Jumpin’ Jack Flash

If you don’t have a load tester and are feeling adventurous, a big set of pliers (be sure to insulate yourself with gloves, etc. first!) can be used from pole to pole to see if the spark is substantial. The bigger the spark, the more charge you have in your battery.

Along the same vein, you can attach jumper cables to the battery, then go to the other end and hit together the two clamps of the other end of the jumper cables. The snap should be big enough to see and hear easily.

These two measures are not recommended, but do demonstrate there are many avenues available to finding out desired information. Caution: Batteries release hydrogen sulfide gas that is extremely explosive when a battery is charging or drawing a large current.

You may try jumping the battery to get the tractor started. If this works, the problem may just be the battery and/or
it’s connections.

And if it isn’t the battery?

If it still doesn’t start, the solenoid or the starter may be the problem. To reduce the likelihood of starter solenoid failure, the battery connections should be cleaned and tightened at every oil change

Where I generally start when there’s a question about not turning over, after confirming battery is okay, is with the solenoid.

Find your solenoid, which may be atop your starter or a “remote” solenoid, mounted elsewhere. Initially, in this step, only focus on the start terminal on the solenoid.

Try jumping from the battery side to the start terminal. What this does is run current directly from the battery to the solenoid, eliminating everything else. Jumping the start side checks the solenoid and starter.

If this works, then the problem is from the battery to the solenoid through the ignition switch.

Ignition switch is fine, what’s next?

Back to our problem solving. If nothing happens when you jump from the battery to the starter terminal on the solenoid, then jump the two big terminals on the solenoid. It should at least click. If the starter engages here, then it’s the solenoid that is faulty. Presuming the battery is good, then it’s the starter. If jumping the big terminals on the solenoid and the starter doesn’t engage the engine, then the starter is at fault.

The starter solenoid receives a large electric current from the battery and a small electric current from the ignition switch. When the ignition switch is turned on, a small electric current is sent to the starter solenoid. This causes the starter solenoid to close a pair of heavy contacts, thus relaying a large electric current to the starter motor, which, in turn, sets the engine in motion. The starter motor is an electric motor that initiates piston motion in the internal combustion engine before it can power itself.

The starter solenoid can be located under the hood of a car/tractor by following the positive (red) cable from the battery, which usually leads directly to the solenoid. Then, the solenoid will have another cable of similar or equal weight which will go down to the starter, which is normally accessed from the bottom of the vehicle.

The solenoid will also have a third (smaller) wire, which comes in from the starter switch. Starter solenoids can also be built into the starter itself, often visible on the outside of the starter.

If a starter solenoid receives insufficient power from the battery, it will fail to start the motor, and may produce a rapid clicking or clacking sound.

The lack of power can be caused by a low or dead battery, by corroded or loose connections in the battery cable, or by a damaged positive (red) or ground (negative) cable from the battery.

Any of these problems will result in some, but not enough, power being sent to the solenoid, which means that the solenoid will simply make a clicking sound, rather than setting the starter motor in motion.
In summary:

  1. Make sure the battery is up.
  2. Bypass ignition switch by jumping the solenoid.
  3. Bypass the solenoid by jumping to the starter.

If you do these steps, you should be able to identify where the weak link is in the system and address the problem spot. If nothing works when you get to Step 3, then the starter is bad. This is a quick way of diagnosing what the problem is within five minutes.
Good luck,

Yours in the shop (the dirt is frozen and heat is on in the shop),

Albert

Tags: Batterries, Battery, Engine, Ignition, Solenoid, Starting, Tractor, Wiring

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