69 Mechanical Tach
Thread Starter
Instructor
Joined: May 2015
Posts: 133
Likes: 12
From: Maple Valley WA
69 Mechanical Tach
Ok so the tach works fine when the cable is engaged. It seems that the end of the cable that goes into the distributor is a bit worn and there is a good 1/4" of play back and forth along the cable to where it backs itself out of the drive and will stop working. The cable is not broken or bound up, when it stops working I can unscrew the cable and put it back in and it will work for a mile or two then stops again. Anybody have thoughts on this? Is there supposed to be something on the cable to prevent the 1/4" of play? I'm thinking of cleaning it and putting some lock tight on it to prevent it from coming out, not my first choice but I don't care to replace the cable if I don't have too. Thanks in advance. 
Safety Car
Joined: Apr 2006
Posts: 4,057
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From: BC
Ok so the tach works fine when the cable is engaged. It seems that the end of the cable that goes into the distributor is a bit worn and there is a good 1/4" of play back and forth along the cable to where it backs itself out of the drive and will stop working. The cable is not broken or bound up, when it stops working I can unscrew the cable and put it back in and it will work for a mile or two then stops again. Anybody have thoughts on this? Is there supposed to be something on the cable to prevent the 1/4" of play? I'm thinking of cleaning it and putting some lock tight on it to prevent it from coming out, not my first choice but I don't care to replace the cable if I don't have too. Thanks in advance.
Former Vendor
Joined: Aug 2006
Posts: 76,656
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Ok so the tach works fine when the cable is engaged. It seems that the end of the cable that goes into the distributor is a bit worn and there is a good 1/4" of play back and forth along the cable to where it backs itself out of the drive and will stop working. The cable is not broken or bound up, when it stops working I can unscrew the cable and put it back in and it will work for a mile or two then stops again. Anybody have thoughts on this? Is there supposed to be something on the cable to prevent the 1/4" of play? I'm thinking of cleaning it and putting some lock tight on it to prevent it from coming out, not my first choice but I don't care to replace the cable if I don't have too. Thanks in advance.
The run out on the gear should be .10 aprox..
The cable is reverse wound which will thrust the cable toward the tachometer but there shouldn't be that much free play and this is why I say I'd go with a new cable first. The cable will also pull in any excess grease on the cable so never over-lube the cable.
Willcox
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Instructor
Joined: May 2015
Posts: 133
Likes: 12
From: Maple Valley WA
I'd probably replace the cable but are you sure there isn't any issue with the driven gear? Have you pulled the coupling and looked at the gear.
The run out on the gear should be .10 aprox..
The cable is reverse wound which will thrust the cable toward the tachometer but there shouldn't be that much free play and this is why I say I'd go with a new cable first. The cable will also pull in any excess grease on the cable so never over-lube the cable.
Willcox
The run out on the gear should be .10 aprox..
The cable is reverse wound which will thrust the cable toward the tachometer but there shouldn't be that much free play and this is why I say I'd go with a new cable first. The cable will also pull in any excess grease on the cable so never over-lube the cable.
Willcox
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
The distributor was rebuilt by a reputable member on the forum and has about 100 miles on it since so i don't suspect the distributor. By driven gear are you referring to the tachometer itself? If so I have stuck my head up there several times and cannot see much of the backside of the tach, I'm 6'4" 240 so it is quite cramped for me and thats one reason I'm not looking forward to a cable replacement.
I'm 6-4 used to be 300 lbs.. lol. So I know that pain.. I'm now 200 lbs though diet and exercise and I've been a runner now for the past couple of years and go I don't miss the extra baggage. What is neat about this is I've got a horrible spinal fusion and I've been in this business since 1973.... so lets not talk about age..
Ernie
Last edited by Willcox Corvette; Jun 1, 2016 at 11:27 PM.
Thread Starter
Instructor
Joined: May 2015
Posts: 133
Likes: 12
From: Maple Valley WA
Your not going to see anything.. The driven gear is in the distributor so if you are sure it's okay then I'd move to the tach cable. (I'd still check it regardless).
I'm 6-4 used to be 300 lbs.. lol. So I know that pain.. I'm now 200 lbs though diet and exercise and I've been a runner now for the past couple of years and go I don't miss the extra baggage. What is neat about this is I've got a horrible spinal fusion and I've been in this business since 1973.... so lets not talk about age..
Ernie
I'm 6-4 used to be 300 lbs.. lol. So I know that pain.. I'm now 200 lbs though diet and exercise and I've been a runner now for the past couple of years and go I don't miss the extra baggage. What is neat about this is I've got a horrible spinal fusion and I've been in this business since 1973.... so lets not talk about age..
Ernie
Thread Starter
Instructor
Joined: May 2015
Posts: 133
Likes: 12
From: Maple Valley WA
I replaced the cable and it solved the problem, I compared the length of the ends that go into the distributor of the old and new cable with them pulled all the way out. The old cable was about 1/4" shorter than the new one and it might have been worn down from not being inserted properly. You can it in the attached pic. The new cable was a couple inches longer than the old one but much more pliable so it went in easily.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,851
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I replaced the cable and it solved the problem, I compared the length of the ends that go into the distributor of the old and new cable with them pulled all the way out. The old cable was about 1/4" shorter than the new one and it might have been worn down from not being inserted properly. You can it in the attached pic. The new cable was a couple inches longer than the old one but much more pliable so it went in easily.
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