Rambo fan issue

[noddynomolos]

Dear Group,
I have one of the old Rambo boards and am presently running Repetier 0.85b on the Repetier Sketch_Mar02a firmware.
I have not upgraded to the latest firmware.

Background info:
Since installing the EZstruder I have run into a brick wall... the hob gear eats through the filament and makes a real mess. This is due to the hotend jamming. When I the filament out of the hotend there is a visible thickening on the leading end of the filament. I have checked the hotend with a thermocouple and it is running about 5 degrees C above my Repetier temperature read out. I have recently replaced the nozzle with the new variation. I have also adjusted the teflon tubing to reconfigure it for the new nozzle (though have a further question about that).

Fan /Rambo issue:
I have acquired a 40mm 12v fan and plugged it into the Fan0 port.. From Repetier I ran the m106 command and got no response. I then moved the fan to the Fan1 port and tried the m106 command and no response.. On another thread I had read to use m42 p6 s255 so I tried that as well on both Fan0 and Fan1..
There is a small red LED that lights up on the rambo just below the heat0 port and above the jumpers... Further, I can turn this same LED on and off with the fan button on the Repetier control (in the manual tab).

Questions:
Is there a jumper I am missing on the board?
Is there a software command I must add to the firmware?
Should I even bother with the rambo and just run directly off the power supply?
Any suggestions would be greatly appreciated?
Yours,
Don S

[Eaglezsoar]

What is the fan being used for and what type of filament are you using that plugs the hotend?

In addition what printer are you using?

[noddynomolos]

Hi Eagle,
I have a RostockMax and am printing in ( good quality) ABS.
I have some PLA but have not tried printing with it yet.. I figured one challenge at a time
The fan will be mounted on the hotend once I work out the power (to fan) situation.
I was reading another thread that talked about the teflon tube possibly being the issue (narrowing due to over heating and build up). So I will pull the tube and carefully run a dremel through it to remove any build up..

[geneb]

There is no build up in the tube - if the PTFE liner gets over heated, it will shrink a small amount, just enough to prevent filament from passing through it - you need to replace it if it's in that condition.

If the fan is known good (tested) and you use FAN0, the fan slider in Repetier-Host should activate it. M42 P6 255 will turn on the fan if connected to FAN1.
If you're seeing the LED lamp for HEAT 0 coming on when you move the fan slider, try connecting your fan to it - if the fan runs off HEAT 0, you've got serious pin configuration issues going on.

AFAIK, there is no known Repetier firmware version named "Sketch_Mar02". What _version_ of the firmware are you using. Note that if you're using v0.85 of Repetier Host, you're about 10 versions out of date. It's currently at 0.95F.

g.