Help hard / no start Kohler CH25 see video

[MNBen]

Oi when I jump the solenoid if fires hard and fast, but when I use the key it click or drags/bogs trying to turn over the engine. 98% of the time it clicks and after maybe 3 turns of the key it will turn over. I have smacked the solenoid with a wrench while holding the key and it would then crank.
The contacts have been cleaned... I guess I could/should change the positive wire as I did see some green corrosion inside the end of the cable.
I just don't understand why it bogs down using the key, like something is robbing the volts and not applying it to the solinoid.

 

[Mark H_NO]

When you jump the solenoid, are you jumping from the battery terminal to the starter? If so, your solenoid could be bad.

 

[MNBen]

When you jump the solenoid, are you jumping from the battery terminal to the starter? If so, your solenoid could be bad.

The solinoid is new. Actually I have 2 brand new and the original solenoids. They all act the same way.
The jumper wire is from the S (start) terminal to the solenoid stud that connects directly to the battery.

 

[Mark H_NO]

Sounds like the switch, or wires/connections.

 

[Scrubcadet10]

https://www.amazon.com/dp/B0B8W8M3W6?ref=nb_sb_ss_w_as-reorder_k0_1_25&amp=&crid=2D5WKRELPQNP6&amp=&sprefix=starter+improvement+relay

You may need something like this.
somewhat common issue on older equipment that uses a solenoid shift starter.
red wire goes to Battery Positive on solenoid.
male purple goes to old trigger wire
female purple goes to trigger on solenoid
black to a good ground,.

 

[sgkent]

do you own a volt meter?

 

[Tiger Small Engine]

do you own a volt meter?

You are experiencing voltage drop. Check with multi-meter when cranking engine. Need to clean and check grounds, clean and check all red power wires.

 

[MNBen]

Sounds like the switch, or wires/connections.

A mobile repair person mentioned he has experienced this in the past and the switch is going bad. I will look into this.

 

[MNBen]

do you own a volt meter?

Yes, 3 of them.

 

[MNBen]

You are experiencing voltage drop. Check with multi-meter when cranking engine. Need to clean and check grounds, clean and check all red power wires.

I did see a little green corrosion in the hot wire end at the battery. I did not think much of it until cleaning all the contact points did no improvement. The thing is, this corrosion is still present when I jump the solenoid and it fires strong. So I'm thinking somewhere else. A mobile tech mentioned the my ignition switch is going bad.