IS3100Z Big Block Starting Issues

Hammermechanicman

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I have a Ferris IS3100z Big Block (32HP) and its' having starting problems. When you attempt to start it the solenoid might click once or twice to as much as 30-40 times before it engages the starter. I replaced the solenoid and it worked fine for a few days. Then it would do it occasionally but now it is back to being a constant problem. Up to this point it has always ended up starting but it continues to get worse and worse. Any thoughts?
Another thing to try is to turn the key to start and when it clicks and doesn't start hold the key in the start position and hit the starter with a rubber mallet a few times. If it engages when hit you have a bad starter.
 

Scrubcadet10

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What should the voltage read when the key is in the starting position?
at rest the battery should be around 12.5 volts, 12.2 at the minimum, when starting the battery shouldn't drop below 10 volts.
 

lawnboy427

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at rest the battery should be around 12.5 volts, 12.2 at the minimum, when starting the battery shouldn't drop below 10 volts.
Thanks for all the helpful replies. I won't be able to get back to it until tomorrow to put a meter on it while in the start position. I will also try jumping the terminals on the solenoid but I am still thinking this is a ground issue. Thanks again!
 

bertsmobile1

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Forget the multimeter
Go back with some jumper leads
The fastest & surest way to check battery connections is to bypass them, one at a time with known good jumpers .
Start with a battery ground directly to the engine near the starter.
Because ZTR wiring is exposed to the elements and in particular due drop and the wires are all crimped not soldered, water wicks into the wires and corrodes them under the plastic insulation where you can not see it.
And remember the solenoid itself needs a good ground , particularly is it has only 1 trigger wire and grounds through its body to the mower.
 
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bertsmobile1

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Just guessing but I would think nothing below 11.3V
No use guessing Bob
The voltage has the be 10V to trip most starting solenoids and 9V or better to trip the fuel solenoid
But numbers are for politicans to lie about & accountants to manipulate to justify their bonuses
This is why I always advise to bypass using jumper cables and forget about getting the right numbers.
In the work shop I have a dedicated continuity meter that buzzes loudly and a test lamp with the thin probe insulated for most of it's length .
These are quicker and give better results.
The test lamp has a H4 globe in it soit pulls power.
Way too many hours wasted becaue a meter showed continuity but the circuit failed when ever you try to pull a few amps through it.
 
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