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Starter problems

#1

W

whiteshu

The starter/solenoid on my FD750D engine just clicks often when I try to start. This happens when the engine is warm. If I click it often enough it will start. When this happened to our GM cars back in the 1960s we pulled the solenoid and cleaned or replaced the the copper washer and or contact studs. Is this the same or something more complicated (expensive). The engine is in a John Deere X738 with 580 hours.


#2

T

txmowman

Learn voltage drop, it will be your best friend.


#3

R

Rivets

First thing to check are battery cable connections, both on the battery and solenoid, plus negative chassis ground. Make sure each one is clean and tight, especially the negative to chassis, which likes to come loose and get dirty. After you know they are all good, as stated, check battery voltage drop. To do so connect a volt meter across the fully charged battery. Turn the key to the start position and observe the voltage reading. If it drops below 10 VDC, time to replace the battery.


#4

S

slomo

Remember all circuits under test need to be fully current loaded. Not an accurate test if you have no current flowing.


#5

W

whiteshu

txmowman said:
Learn voltage drop, it will be your best friend.
Click to expand...
Thanks txmowman: I have not checked voltage drop, but I have a clue. The John Deere parking brake ON makes the problem worse, PUSH the brake petal when trying to start seems to help. I think if I connect an analog meter to the circuit it will show this.


#6

W

whiteshu

Rivets said:
First thing to check are battery cable connections, both on the battery and solenoid, plus negative chassis ground. Make sure each one is clean and tight, especially the negative to chassis, which likes to come loose and get dirty. After you know they are all good, as stated, check battery voltage drop. To do so connect a volt meter across the fully charged battery. Turn the key to the start position and observe the voltage reading. If it drops below 10 VDC, time to replace the battery.
Click to expand...
Thanks Rivits: I have checked the things you mentioned. I have replaced the battery. How many volts should a solenoid require to function propertly?


#7

R

Rivets

Knowing how to properly use a good analog meter is better than using a cheap digital meter. Cheap analog meters aren’t worth their cost. Your engine needs a battery with a minimum of 350 CCA, anything smaller could be part of the problem. Bad connections through the safety switches in the starting system can also cause a loss of voltage. What voltage you need to activate the solenoid depends on the size and type of starter. I would say a minimum of 11 VDC would be recommended, but CCA are more important than volts in the starting circuit. Finally, electrical troubleshooting is the least favorite thing a tech wants to get into. Knowledge, patience, and never assume even the simplest things are your friends. Check everything twice before going to the next step.


#8

A

Auto Doc's

whiteshu said:
The starter/solenoid on my FD750D engine just clicks often when I try to start. This happens when the engine is warm. If I click it often enough it will start. When this happened to our GM cars back in the 1960s we pulled the solenoid and cleaned or replaced the the copper washer and or contact studs. Is this the same or something more complicated (expensive). The engine is in a John Deere X738 with 580 hours.
Click to expand...
Hello whiteshu,

It helps us help you by providing the PIN label information off of your machine. This rider was built for a number of years since 2013 and had serial number breaks that usually indicates that changes were made during production.

Generic advice:

If you can bridge across the 2 main starter mounted solenoid posts and it cranks fine, it will be in the cranking controls or safety switch/ wiring. That also confirms the battery is strong and the solenoid can activate to turn the engine.

If it acts weak, then there is a battery or battery cable end issue robbing the circuit power.


#9

R

RayMcD

Rivets said:
Knowing how to properly use a good analog meter is better than using a cheap digital meter. Cheap analog meters aren’t worth their cost. Your engine needs a battery with a minimum of 350 CCA, anything smaller could be part of the problem. Bad connections through the safety switches in the starting system can also cause a loss of voltage. What voltage you need to activate the solenoid depends on the size and type of starter. I would say a minimum of 11 VDC would be recommended, but CCA are more important than volts in the starting circuit. Finally, electrical troubleshooting is the least favorite thing a tech wants to get into. Knowledge, patience, and never assume even the simplest things are your friends. Check everything twice before going to the next step.
Click to expand...
Hi Rivet, well said about the analog meter, my Chief used to go to Radio shack and purchase all the returned faulty meters, bring them on-board, use them for training, repair and sell to the crew for little to nothing. If your 12 volt battery drops below 12 volts it either needs charging or is suffering from a bad cell and needs replacing. r


#10

StarTech

StarTech

It doesn't matter if the battery is new or used, they all have internal resistance that will cause a voltage drop under a load. Heavier the load the more of voltage drop. As the battery ages this internal resistance increases.

Now used batteries do develop internal problems such as internal shorts and plate sulfation. Some can even sudden develop an open circuit condition. They can have their cases to become conductive which cause batteries to self drain.


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