GR3750 T3 drum problem

[ianmck]

When I swtich drums and put in my oldest drum and try to make a new master the drum turns for a while then halts on a T3 error.

On extracting the drum I note the clamp on the drum is open and the master still in place and the drum is not quite locked in position. If I flip the clamp back to hold the master again and turn the drum until it locks and re-try it will repeat the error with the same symptoms. If I continue to repeat this procedure it will eventually remove the old master and make a new one.

The last time the error occurred I removed the master manually, re-set the clamp and locked the drum. This time it worked first time. Looking at the clamp I can see that some of the strips that lift the edge of the master when the clamp is open are missing. I suspect that replacing these strips will solve the problem but before I spend any money I wanted to see if anyone else could advise. Any help appreciated.

[RRodgers]

It's been a real long time since I've been at one of these, but check to be sure that the master is popping up so the claw (master removal claws) will pick it up and peel it off the drum.

[joelsa12]

you say that the drum turns for awhile.... then it t-3s. so that is all that it is doing is turning? if this is a correct statement then I would bet that you have a position "a" issue. I would pull the bottom cover off the drum and blow it out. there are flag sensors mounted to a board that tell the drum when it is in the right position. it sounds like it is searching for home but can not find it. also with this being your oldest drum it also makes me believe that there has been a longer time for dust to build up in this sensor. good luck and keep us posted

[ianmck]

Tried cleaning the flag sensors but no joy

I took the bottom cover off and cleaned around the pcb and connectors but the problem persists. Manually re-seting the drum in position and flipping the clamp over and re-running the machine eventually hgets a solution. Once it has done it sucesssfully it is OK after that.

The problem seems to be with the master removal, though when I tried it without a master I had the same problem this time.

I noticed the master edge is lifting very clear when the clamp is open so don't think my original thinking it was the poor state of some of the strips under the clamp was correct.

Thanks for an help.