Konfusing Kohler

[puttinalong]

What I am trying to figure out: Cub Cadet Model #13AQ92AP010 with a Kohler SV730-0011 with 122 hours. This is the short and sweet of it:

- Neighbor can't get it started, so I go and see the starter gear is stuck and free that up and clean it up. Put it back on his mower and it turns and retracts as it should.
- Neighbor tries to start it and it is sluggish and will hardly turn over. (He has a new battery with only 160 CCA so I use mine that has 350 cranking amps/420 CCA) My battery turns the engine better but it still won't start.
- Neighbor says: "Yeah, I notice when I put a jumpbox on the mower to start it with a good battery it will give it the extra UMPH and it normally would start."
- So my buddy hooks it up and Voila! It acts sluggish initially but had a little more pep and started it up.
- I took my battery off of it and put his back on and it started, but reluctantly so.

Would this be indicative of the compression release gone in the engine? Thank you for your time.

[KE4AVB]

Usually when the ACR is bad starter turns the engine until reaches near TDC of a compression stroke and then stalls out. If it slow turning overall then it can bad connections; or dirty commutator ring or worn brushes.

What is the voltage across the battery while cranking vs across the starter? Both voltages must be with 1 vdc of each other. If more than 1 vdc difference then there is voltage loss due a bad connection or contact on the positive side or a bad ground. Note static battery voltage before cranking should be 12.4 vdc and while cranking must 9 vdc or higher.

Also if you can measure the cranking amp draw what is it? Should be somewhere around 80-90 amps normally but can be higher.

[puttinalong]

Thank you KE...I will attempt to go back to his house tomorrow and befuddle my way through it. Still learning electricity and how to work multimeters....thank you now for your patience, I may have some questions once I get started.

[Luffydog]

Also these engines a famous for shaking the motor bolts from the frame so that will play In while checking the ground at the engine block as well as the ground cable itself.

[puttinalong]

Well...long story short, replaced both battery cables and fixed the problem. Thanks to all!