tach driven gear question

[Werner R.]

i'm near the end of the distributor rebuild. is there a trick to determining the correct "end play" in the cross shaft. what happens is that if i screw in the cable coupler all the way then the cross shaft nearly seizes. howeever, if i loosen the coupler even one half turn then everything is fine. is it ok to install the coupler "a little loose". that does not seem good to me because it will allow some slight wobble in the cross shaft. any advice will be appreciated.
werner

[William C.]

Re: tach driven gear question

A little end play is preferable to tight, but I would not use the brass bushing as an adjustment tool. Either adjust the thickness of the washer between the gear and the bushing or adjust the thickness of the new stop you must have installed in the bottom of the gear cavity. There should be no drag with the bushing tight.

[Werner R.]

Re: tach driven gear question

bill
makes sense to me. i will make the bushing tight and then adjust as you have indicated. i have been playing with this with combinations of washers between the "shaft and bushing" and between the "plastic stop and metal housing" and even 20 thousandths really makes a difference.
have you ever shaved off the bushing where it makes contact with the cross shaft to "increase end play" [ie to slightly shorten the brass bushing]????
werner

[William C.]

Re: tach driven gear question

Last one I did with one of the currently available "bushings" required removal of the small washer between the crossshaft and the coupler to get free movement. A little freedom more is likely better than tight in this area.

[William Holder]

Re: tach driven gear question

Werner,
I have the exact same problem. i do not even have a washer between the cross shaft and the coupler. I just assumed it was because I was using aftermarket parts.Please let me know how it goes!
Thanks
bill

[Werner R.]

Re: tach driven gear question

i put it together this weekend. with the thrust washer the unit was "seizing". i removed the washer and i could still detect some drag, but it was much better than with the washer in place. i then laid a flat file on my bench and rubbed the new unit to shave off a "touch" of the face. this helped. i am satisified now that i have done as much as i can. the unit turns freely with no noticeable drag. i think any problem is a combination of the aftermnarket coupler and the black plastic thrust button. before i put this together i screwed around with an extra black thrust button [which i think my hardware store carries for $0.35]. i sanded a little off of the face and that seemed to help a little also. i suspect that perfection will elude us unless we are machinists that can finely shave the coupler and can also manufacture a thrust button.
i still would like to try the idea that someone raised which was to take the distributor housing [mine is from an early 70's car and therefore has a hole for the thrust button] and tap the hole to accept a set screw and use this to fine tune the thrust against the cross shaft. it makes sense in theory and one of the guys said it worked for him. another fellow said you have to be nuts to do this. so it goes....[on the one hand; but then on the other...]
werner
thanks for your advice