Speedometer & Tach cables?

[Mike F.]

I'm pulling the engine, so the speedometer & tach cables will be disconnected at the transmission & distributor.
Can I simply pull out the drive cable, clean/lube, and re-install with the cables falling back into place in the rear of the speedometer and tachometer or must the connections at the rear of the gauges be disconnected as well?


TIA,
Mike

[Terry M.]

Re: Speedometer & Tach cables?

I'm pulling the engine, so the speedometer & tach cables will be disconnected at the transmission & distributor.
Can I simply pull out the drive cable, clean/lube, and re-install with the cables falling back into place in the rear of the speedometer and tachometer or must the connections at the rear of the gauges be disconnected as well?


TIA,
Mike

Mike,
There is no need to disconnect the speedometer cable to remove the engine alone. If you are also removing the transmission then you will have to disconnect the speedometer cable.

I think I know the answer to the rest of your question, but I have no personal experience, so I will defer to those who do. One other point: The answer for the speedometer portion of the question may depend on the kind of transmission you have. I know some M40s have a two piece speedometer cable, and that may make a difference.

[Gordon W.]

Re: Speedometer & Tach cables?

I'm pulling the engine, so the speedometer & tach cables will be disconnected at the transmission & distributor.
Can I simply pull out the drive cable, clean/lube, and re-install with the cables falling back into place in the rear of the speedometer and tachometer or must the connections at the rear of the gauges be disconnected as well?


TIA,
Mike

Yes, no need to disconnect from gauges. When you slide the cable back in you can rotate it as you push and it will engage.

[Joe L.]

Re: Speedometer & Tach cables?

I'm pulling the engine, so the speedometer & tach cables will be disconnected at the transmission & distributor.
Can I simply pull out the drive cable, clean/lube, and re-install with the cables falling back into place in the rear of the speedometer and tachometer or must the connections at the rear of the gauges be disconnected as well?


TIA,
Mike

Mike-----


The cable CORES (the part that turns) cannot be removed from the transmission or distributor end. They can only be removed from the instrument end.

[Gordon W.]

Re: Speedometer & Tach cables?

Mike-----


The cable CORES (the part that turns) cannot be removed from the transmission or distributor end. They can only be removed from the instrument end.

My tach cable core slid out just fine from the generator end and installed back without problem.

[Joe L.]

Re: Speedometer & Tach cables?

My tach cable core slid out just fine from the generator end and installed back without problem.

Gordon-----

C1 cables may be different. I don't think that C2 or C3 cable cores will remove that way.

Here is a photo of the TYPICAL configuration of a C2 or C3 cable core. Note the "annular ring" at the instrument end (the end dyed orange on this cable). This is what prevents the cable from being removed from the transmission or distributor end.speedometercable(typical).JPG

[Dennis C.]

Re: Speedometer & Tach cables?

Gordon-----

C1 cables may be different. I don't think that C2 or C3 cable cores will remove that way.

Here is a photo of the TYPICAL configuration of a C2 or C3 cable core. Note the "annular ring" at the instrument end (the end dyed orange on this cable). This is what prevents the cable from being removed from the transmission or distributor end.[ATTACH=CONFIG]42964[/ATTACH]

Joe,

C1 cables have the same type end fitting. AC replacement core cables come with that piece loose and adhesive in the socket. After installing the replacement core Nd cutting it to the proper size you insert the core in to the socket and warm it. The heat melts the adhesive.

Dennis

[Gordon W.]

Re: Speedometer & Tach cables?

Okay, I thought I had stumbled on a post that I could provide some help but I'm continuously finding out that I have a lot to learn about these cars.

My tach cable innards are reversed with the plastic end (red on my cable) at the generator side. I'll stop assuming that what's on my car is correct.

[Joe L.]

Re: Speedometer & Tach cables?

Okay, I thought I had stumbled on a post that I could provide some help but I'm continuously finding out that I have a lot to learn about these cars.

My tach cable innards are reversed with the plastic end (red on my cable) at the generator side. I'll stop assuming that what's on my car is correct.

Gordon-----


Please don't be discouraged or reluctant to post a response. It's okay to be incorrect. It happens to me all the time. Being incorrect on something is a great way of learning something new. For instance, how would you have learned that your installation is apparently incorrect if you had not posted? I've learned stuff the same way.

[Jim T.]

Re: Speedometer & Tach cables?

Terry my 1970 equipped with the turbo 400 has a two piece speedometer cable. Makes it easy to lubricate that half of the speedometer cable connected to the transmission plus you do not have to worry about lubricant migrating into the speedometer head from that end.

[Terry M.]

Re: Speedometer & Tach cables?

Terry my 1970 equipped with the turbo 400 has a two piece speedometer cable. Makes it easy to lubricate that half of the speedometer cable connected to the transmission plus you do not have to worry about lubricant migrating into the speedometer head from that end.

Jim, I have seen 1968-1972 (not all of them I just can't remember the year(s) Mark IV M40 with the two piece speedometer cable. I just wasn't sure what had them and what didn't -- so rather than get into that quagmire I let it rest at "some." I thought the bottom line was we needed more information (transmission type at least) to advise properly. But then I was not going to get into the cable core area anyway.

Thanks for the info, though. I am learning more and more all the time.

[Jeffrey S.]

Re: Speedometer & Tach cables?

My '69 350/300 automatic has a 2 piece cable.
Jeff

[Mike F.]

Re: Speedometer & Tach cables?

I'm pulling the engine, so the speedometer & tach cables will be disconnected at the transmission & distributor.
Can I simply pull out the drive cable, clean/lube, and re-install with the cables falling back into place in the rear of the speedometer and tachometer or must the connections at the rear of the gauges be disconnected as well?


TIA,
Mike

I guess I should have provided a bit more information. I am pulling the engine & transmission (L-46/M21) out as one unit. The tach runs fine, but the speedo seems to be about 6mph off at all speeds. When low on the scale (under 15mph) the needle has a 6mph bump in it that comes and goes.
Was hoping I could pull out the core of each cable, lube, inspect gear, etc., and re-install.

Mike

[Terry M.]

Re: Speedometer & Tach cables?

I guess I should have provided a bit more information. I am pulling the engine & transmission (L-46/M21) out as one unit. The tach runs fine, but the speedo seems to be about 6mph off at all speeds. When low on the scale (under 15mph) the needle has a 6mph bump in it that comes and goes.
Was hoping I could pull out the core of each cable, lube, inspect gear, etc., and re-install.

Mike

Has the differential gear or transmission been changed? If yes, the speedo gear in the Trans may need calibration & replacement. If you don't know about either of these possible changes, some details can be helpful to determine what might have happened -- but best to go into those only if needed.

Otherwise my bet is on the speedo head unit. Of course lubricating the speedo & tach core are a good idea as a part of routine maintenance. From the other posts it sounds like both of those will have to be accomplished from inside the car.

[William F.]

Re: Speedometer & Tach cables?

I was going to address this "being incorrect" for some time.; so, this seems the appropriate time. Not poking at anyone in this thread but in general.Yes, it's Ok to be incorrect but I see threads where members say 'I don't know anything about (whatever) but go on to give definite opinions. IMHO, if you don't really know, either don't reply, or say you don't know and defer to someone with real knowledge on the subject. You kind of get to know who is knowledgable and who just doesn't have anything better to do than give an unfounded opinion after a while.