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Speedometer Cable Grommet

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Old Dec 21, 2014 | 04:55 PM
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Default Speedometer Cable Grommet

Sort of insignificant in the scheme of restoration things, but thought I'd pass a little grommet info your way... This is the speedometer cable grommet that snaps into the firewall, and on a '72, the hole is just above the fuse block, to the right side of the steering column and brake booster.

First thing you'll notice is that the hole in the grommet is way smaller than what you're trying to push through it! There are a few suggestions on here, but after an hour of futsing with it, I decided to just cut a slit, and still had to use needle nose pliers for some leverage. That sucker is tight!

A couple members have said that with enough effort you can get the fitting through the grommet. I tried heat, grease, and dial-a-prayer. Nothing! Cutting a slit was the answer for me. You can't cut all the way through it since there's a metal ring embedded as part of the 3 snap-in tabs, but that's ok. Once the cable was inserted (still needed lots of effort) you could not see the cut, but wouldn't you know it, the grommet's hole was still a little too large for a good cable seal.

Here's a note for manufacturers. When you sell new speedometer cables, install the grommet as part of the package! Just makes sense.

I siliconed the grommet in place on the engine compartment side and sealed the interior with some soundproofing material that I've been using (Ensolite). Should be good to go.

Now to get back out there to run the tach cable. Here we go again!
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Old Dec 21, 2014 | 06:37 PM
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I can get that grommet on the cable with out having to cut anything. By myself...if all goes well...less than a minute. It is QUITE SIMPLE of a process if you stop and THINK about what you are trying to do...and what can make you achieve what you are trying to make the GROMMET do. SERIOUSLY SIMPLE .

DUB
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Old Dec 21, 2014 | 07:39 PM
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Originally Posted by DUB
I can get that grommet on the cable with out having to cut anything. By myself...if all goes well...less than a minute. It is QUITE SIMPLE of a process if you stop and THINK about what you are trying to do...and what can make you achieve what you are trying to make the GROMMET do. SERIOUSLY SIMPLE .

DUB
Really? So tell us how you did it so seriously simply.
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Old Dec 22, 2014 | 06:48 PM
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Originally Posted by ncvettes
Really? So tell us how you did it so seriously simply.
SERIOUSLY.....Did you think about it at all????

QUESTION 1: What are you wanting the grommet to physically do to get it on the cable????

QUESTION 2: How would you achieve the answer to question 1????

And do not use 'reverse psychology' to get me to tell you like writing that I do not know how...because I REALLY DO KNOW HOW.

DUB
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Old Dec 23, 2014 | 12:00 AM
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Originally Posted by DUB
...because I REALLY DO KNOW HOW.

DUB

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Old Dec 23, 2014 | 06:43 AM
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Well..........I'm not one to leave a sleeping dog alone!

Willcox is shipping my new grommet (along with a box of other goodies) as we speak.

"I'm gonna make Dub proud of me".....and slap that stuff together in 43 seconds!

*errrrrrr....as soon as the box arrives at the front door----if nobody steals it!*

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Old Dec 23, 2014 | 01:35 PM
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A High Noon shootout!

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Old Dec 23, 2014 | 06:25 PM
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SERIOUSLY...If I tell you...you will feel really....uhhhh.....( you fill in the blank).

doorgunner.....I have ALL the confidence in you that you can get this in 43 seconds. NO JOKE.

ncvettes: Why don't you post you thought(s) to question 1. Give it a try. I am not trying to mock you...because I know you know the answer...and just don't know that you do know it...THAT'S ALL>

DUB
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Old Dec 23, 2014 | 07:00 PM
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I'm sure the factory installed grommet on the speedo cable is slid on the cable before the end is cripped on. just like the fiber optic grommet.
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Old Dec 23, 2014 | 07:20 PM
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Originally Posted by LT-1 kid
I'm sure the factory installed grommet on the speedo cable is slid on the cable before the end is cripped on. just like the fiber optic grommet.
DOUBTFUL... because usually when a part is on another part....it is then a part of an assembly....which I do not think this grommet is. Because when I used to buy speedometer cables from GM...the grommet was never on it....and I had to figure out how to swap it to the new cable.

DUB
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Old Dec 23, 2014 | 08:28 PM
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some how the grommet got on the cable, I doubt that some factory worker was fidling around trying to wedge a grommet over the big side on a cable, I know about multlble parts being an assembly, thats most likley what was done.
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Old Dec 23, 2014 | 09:27 PM
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I need to know this too. My car has no grommet and I need to plug that hot air source. Unfortunately I'll have to unhook the speedo cable from behind the speed-o-meter.
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Old Dec 24, 2014 | 11:32 AM
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Hi,
The grommet and cable appear to have come to the production line as 2 separate parts since they're listed with 2 part numbers.
71 AIM, UPC12, Sheet C2.5, Items #1 and #4.
The 'shaft' is called an 'assembly' which usually means it's assembled parts when it gets to the line, like the trailing arms or front spindles.
So ??
Regards,
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Last edited by Alan 71; Dec 24, 2014 at 11:46 AM.
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Old Dec 24, 2014 | 03:16 PM
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so Alan, do you think the grommet was installed on the cable as an assembly
or pushed onto the cable on the line.
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Old Dec 24, 2014 | 04:23 PM
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Hi,
If we're to believe the AIM it was put through the grommet on the production line.
But, this wouldn't be the first time the AIM lied to us because the production line did something in a different way that made it better/easier/faster for production.
Still a ?.
Regards,
Alan
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Old Dec 24, 2014 | 04:37 PM
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Originally Posted by Alan 71
Hi,
If we're to believe the AIM it was put through the grommet on the production line.
But, this wouldn't be the first time the AIM lied to us because the production line did something in a different way that made it better/easier/faster for production.
Still a ?.
Regards,
Alan
I purchased a new cable and grommet from Willcox> I absolutely could not get the new grommet on the cable. I re-used the old grommet and went on with my life with a smile.
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Old Dec 24, 2014 | 05:27 PM
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Dub, I am guessing here, but can you stretch the hole wider either with or without heat, by using a pair of needle nose pliers? I have done this at work for hydraulic "O" rings. Lou.
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Old Dec 24, 2014 | 06:09 PM
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LT-1 kid.

You obviously have never worked in major manufacturing facility. I have and I ave seen a lot....which is why it would not be a big deal to install it at the factory. Putting this grommet on would have had a tool that would have taken no time.

I will take the time to look in my GM part illustration catalog and see if the grommet is listed by itself or it will clearly state that it is N.S. ( not serviceable)...which can make it a part of the cable.....or it will state that is IS a part of the cable....and if it is by itself...then it came by itself and was applied......either way...this grommet is not a big deal.


OK...Is every bodies 'thinking caps' on'????

I am surprised that no one wanted to give ideas.....other than 'loup68'.

We KNOW that the grommet has to stretch over the end if the cable that goes to the speedometer.

SO...what I use is a 3/8' drive extension. I apply some die-electric grease on the extension and correctly position the grommet and slide it on the extension......and the end of the extension where you would put your ratchet.....is WIDER....AND...'BINGO'...it oddly enough is as wide as the end of the speedometer cable where it clips into the speedometer.....SO...I clamp the extension in a vise to hold it...and while holding the cable end on the end of the extension where your ratchet goes...I slide the grommet up onto the wider area of the extension and ON the cable....WITHOUT CUTTING ANYTHING.

And if for some ODD reason you can not get the grommet on the extension....that is easy to do also...but I will let you figure that out.

*****REVELATION*****....I just figured out how I can make a tool that does this in a few seconds....so simple of an idea...I just have to get some stock and I will machine one out. My method above works...but this tool is literally idiot proof and so simple I will be able to do it standing in the shop with my hands and not even have to look at what I am doing.

DUB
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Old Dec 25, 2014 | 12:58 AM
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[QUOTE=DUB;1588561329]LT-1 kid.

You obviously have never worked in major manufacturing facility. I have and I ave seen a lot....which is why it would not be a big deal to install it at the factory. Putting this grommet on would have had a tool that would have taken no time.

I will take the time to look in my GM part illustration catalog and see if the grommet is listed by itself or it will clearly state that it is N.S. ( not serviceable)...which can make it a part of the cable.....or it will state that is IS a part of the cable....and if it is by itself...then it came by itself and was applied......either way...this grommet is not a big deal.


OK...Is every bodies 'thinking caps' on'????
So Dub....
What I do is just slide the cable in the pre cut slot then install it in the firewall.
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Old Dec 25, 2014 | 04:57 PM
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Originally Posted by DUB
LT-1 kid.

You obviously have never worked in major manufacturing facility. I have and I ave seen a lot....which is why it would not be a big deal to install it at the factory. Putting this grommet on would have had a tool that would have taken no time.

I will take the time to look in my GM part illustration catalog and see if the grommet is listed by itself or it will clearly state that it is N.S. ( not serviceable)...which can make it a part of the cable.....or it will state that is IS a part of the cable....and if it is by itself...then it came by itself and was applied......either way...this grommet is not a big deal.


OK...Is every bodies 'thinking caps' on'????

I am surprised that no one wanted to give ideas.....other than 'loup68'.

We KNOW that the grommet has to stretch over the end if the cable that goes to the speedometer.

SO...what I use is a 3/8' drive extension. I apply some die-electric grease on the extension and correctly position the grommet and slide it on the









extension......and the end of the extension where you would put your ratchet.....is WIDER....AND...'BINGO'...it oddly enough is as wide as the end of the speedometer cable where it clips into the speedometer.....SO...I clamp the extension in a vise to hold it...and while holding the cable end on the end of the extension where your ratchet goes...I slide the grommet up onto the wider area of the extension and ON the cable....WITHOUT CUTTING ANYTHING.

And if for some ODD reason you can not get the grommet on the extension....that is easy to do also...but I will let you figure that out.

*****REVELATION*****....I just figured out how I can make a tool that does this in a few seconds....so simple of an idea...I just have to get some stock and I will machine one out. My method above works...but this tool is literally idiot proof and so simple I will be able to do it standing in the shop with my hands and not even have to look at what I am doing.

DUB
DUB.... That's a lot of work to install a grommet that should be easy to install with a little lubricant and some pressure. The grommet I received from Wilcox was thick and very hard rubber. Nothing close to the original.
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