Tic Toc Tac needle bushings

[Voss]

I'm currently in the process of rebuilding the instruments in my -68 R/T. Now the turn has come to the Tic-toc-tac.

When I move the needle carefully (with the gauge in the up right position, using a toothpick) it moves very easily but does not return by itself to zero. Should the return springs be able to pull back the needle to zero? Could be a case of bad bushings?  

[Dans 68]

That seems to be a common problem with the tic toc tachs. On mine I tried to ease off on the jewel screw, to allow the tach needle shaft to more easily turn. Look at this FAQ sheet from RTE http://rt-eng.com/rte/index.php/RTE_Tach_Faq#My_tach_needle_is_sticking.2C_how_can_I_fix_it.3F. Lots of good information.

Dan

[Voss]

That seems to be a common problem with the tic toc tachs. On mine I tried to ease off on the jewel screw, to allow the tach needle shaft to more easily turn. Look at this FAQ sheet from RTE http://rt-eng.com/rte/index.php/RTE_Tach_Faq#My_tach_needle_is_sticking.2C_how_can_I_fix_it.3F. Lots of good information.

Dan

Thank you Dan for the link. I did clean the bushings, oiled them and finally eased off the jewel screw just a bit. It works like new now. Leasson learnt, it's VERY important that the needle moves completely freely, otherwise you will get that "hanging" appearance of the needle when you drop the rpm. And with the original Borg clock (which I also cleaned up, oiled and fixed) my Tic-Toc-Tac is all good!  

[Dans 68]

That seems to be a common problem with the tic toc tachs. On mine I tried to ease off on the jewel screw, to allow the tach needle shaft to more easily turn. Look at this FAQ sheet from RTE http://rt-eng.com/rte/index.php/RTE_Tach_Faq#My_tach_needle_is_sticking.2C_how_can_I_fix_it.3F. Lots of good information.

Dan

Thank you Dan for the link. I did clean the bushings, oiled them and finally eased off the jewel screw just a bit. It works like new now. Leasson learnt, it's VERY important that the needle moves completely freely, otherwise you will get that "hanging" appearance of the needle when you drop the rpm. And with the original Borg clock (which I also cleaned up, oiled and fixed) my Tic-Toc-Tac is all good!  

You're very welcome.   

Dan