New track motor won't turn

hello,

I have just replaced my track motor and gearbox after the old one disintegrated.

I operated on one track for about 25 hours by removing the sungear from the damaged trackmotorgearbox.

Now that my new motor has arrived and I installed everything, I push the forward and reverse lever but nothing happens. I can hear engine labouring and sounds like fluid trying to get to the motor but it won't turn.

Any ideas? Could operating one one track upset the swivel joint alignment somehow?...

New track motor won't turn

New track motor won't turn