Case 2090 blew transmission filler cap off - PTO problems?

Was using the Case 2090 to pull gravity wagons one night last week. All short distances at slow speeds - tractor wouldn't have even gotten warmed up. Pulled up to the auger and shut tractor down for the night and heard a large bang. Sort of a haze/smoke around the tractor. Thought it have been a hydraulic hose or pipe under the tractor. It was late so I just quit for the night. Next day I started the tractor up and everything worked fine. Later in the day I noticed the transmission filler cap was off. So, I assumed the bang was the cap blowing off and letting some kind of pressure off. The next day while pulling a load I smelled an odor and and smoke was coming from the transmission filler (no cap - can't find it after it blew off). I would have basically just started the tractor up and would have moved a couple hundred feet. I stopped and smoke was still rolling out. I wondered if it was related to the PTO so I moved the knob and could hear a difference in the engine and after pulling it up and down it seemed to disengage and not drag the engine down and the smoke went away. Now the PTO runs constantly. I have not tried to hook up a large PTO load to see if the PTO stops or if it will carry a load. The PTO hasn't been used in years. I did pull the knob up a couple weeks ago and lubed the cable when I was lubing the engine stop cable. I assume I moved it up and down to work the cable lubricant in and that I left it in down position. This smoke event also must have happened the night the filler cap was blown off. Any idea what has went wrong. Transmission works just fine. Did need to change the transmission/hydraulic filters fairly soon as I had weak/no power steering, etc. Hydraulics worked excellent after filter change. Haven't had any smoke coming out of the transmission filler, but the PTO runs continually. Could this happen if the PTO knob was slightly engaged? What happened? Did the PTO brake work against the PTO clutch? Is this something that happens? What did I damage? What are the repairs? Thanks guys.

My guess is the brake is what got hot and there could be a couple reasons for that. Can't say for sure if you might have had it partially engaged or not. Regardless the PTO housing will have to come of and at that time everything will get inspected. You might need all PTO clutch disc's and a brake. The brake can damage the drum assy. and that might need replacing also. I have seen it happen several times that the brake slipped against the drum and got the drum very hot, possibly enough to ignite trans oil fumes. Rod.

Thanks 1370Rod. Your diagnosis is what I sort of thought. Smoke was really spewing out of the filler stem. How do you get to the pto? You must have to take the back cover off???? Thanks

Yes, the trans oil has to be drained and hitch bracket disconnected and a few hyd. lines. Then unbolt the rear cover{PTO housing} and remove. It is not to bad a job. I would have someone familiar with that PTO unit service it if you have never done this before or if you lack the factory service manual. Rod.