Clutch dragging starter?

[Dellbertt]

1951 Farmall Cub all OEM. This tractor has done this forever. I have searched the topic but cant find much.
Starter spins the engine fast and starts instantly.
BUT, if I push the clutch in it won't turn over at all, just grunts and won't turn a bit. Let the clutch out and it whips and starts.
I read somewhere the TOB can create some drag, but that much?
What else could it be.

 

[Rodney51Cub]

Two things I would check are -
1. Throw out bearing.
2. Battery cable at where it go by the clutch pedal.

 

[used red MN]

There is no noise when you push the clutch all the way down when it is running? I would check the crankshaft end play to see if the crank thrust bearing is having a problem. I don’t know what the spec is but I would doubt the max would be much over 0.010”

 

[Charlie M]

I have a 47 Cub with a graphite bearing and I can hear it work the tractor a bit when I depress the clutch so probably on yours its enough the starter motor can't turn over the engine.

 

[Duner Wi]

Use hand crank, clutch up and clutch down , might tell you something.

 

[Dellbertt]

It runs and shifts normal after start. The TOB looked like it had never been greased so I put a generous amount in the fitting. Maybe it will get better after a few hours use.
Thanks for all the help and information.

 

[grandpa Love]

We never try to start a cub while pressing the clutch. It creates a lot of drag. Perfectly normal considering how the throw out " bearing" works.

 

[BarnyardEngineering]

Cubs have a graphite throwout bearing that doesn't spin like a normal throwout bearing. It drags on the engine some making it harder to start. Correct starting procedure is to keep your foot OFF the clutch pedal during starting.

Never heard of one that stopped the engine dead though...

Hopefully you used cheap grease, the kind that separates easily, because it's that separation that lubricates the graphite.