Distributor Rebuild Question..

[Glenn B.]

My tach died lasy week on my 67 Big block. Pulled out the tach coupling today and found the driven gear is chewed up - so looks like I have no choice but to pull the dist and rebuild it (I am assuming the shaft gear is also toast - hard to see while it is installed), but I can see that the driven gear has worn well into the housing - so will add the thrust button.

Found some good posts on dist rebuilding. I am ordering parts tonight and am wondering.... is replacement of the upper and lower shaft bushings recommended as a normal item during a rebuild?

[Joe L.]

Re: Distributor Rebuild Question..

My tach died lasy week on my 67 Big block. Pulled out the tach coupling today and found the driven gear is chewed up - so looks like I have no choice but to pull the dist and rebuild it (I am assuming the shaft gear is also toast - hard to see while it is installed), but I can see that the driven gear has worn well into the housing - so will add the thrust button.

Found some good posts on dist rebuilding. I am ordering parts tonight and am wondering.... is replacement of the upper and lower shaft bushings recommended as a normal item during a rebuild?

Glenn-----


You can measure the ID of the bushings to determine if there is excessive wear. However, to do it you'll need precision snap gauges and micrometer. If the bushings check out ok, then they don't need to be replaced.

[Glenn B.]

Re: Distributor Rebuild Question..

Thanks Joe. Would you happen to be familar with how easy/difficult the busings are to remove and install ? - if it's a simple task I think I will just replace them - as they are not expensive.

[Joe L.]

Re: Distributor Rebuild Question..

Thanks Joe. Would you happen to be familar with how easy/difficult the busings are to remove and install ? - if it's a simple task I think I will just replace them - as they are not expensive.

Glenn-----


It seems like an easy and straightforward sort of job, but it doesn't always turn out that way.

[Jim T.]

Re: Distributor Rebuild Question..

Glen a pretty reference for rebuilding your distrubutor is available at www.tispecialty.com . The article states that the upper bushing does not wear like the lower bushing and may not need replacing.
The bad thing about replacing the distributor shaft in 2008 is that you cannot get an exact replacement. The top piece of your original distributor shaft, if it is the original or an original type replacement should be removed and installed on the replacement distributor shaft. This top piece has a part in the movement of your centrifical advance.
Back years ago when GM was providing replacement shafts, there were a whole lot of different part numbers in their parts book for the different shafts because of the configuration of the top piece.

[Glenn B.]

Re: Distributor Rebuild Question..

Jim - thanks for the heads up on the centrifigal advance, I hadn't envisioned this to be an issue - was more worried about ensuring the cam was correct. The base plate I believe has a "notch out" which limits the mechanical advance - I presume this is what you are warning me of ?

Is there a recommended procedure for "transplanting" an old head onto a new tail? I fear I may be about to bite off more than I can chew here...

[Jeff C.]

Re: Distributor Rebuild Question..

The December 2007 issue of Corvette Enthusiast has an excellent article by John Hinckley on how to rebuild 63 thru 74 tach drive distributors You should definitely get a copy.

[Glenn B.]

Re: Distributor Rebuild Question..

Thanks Jeff - just found and purchased a copy on fleabay - hopefully it will show up within the next week.