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RocketSurgeon Sat May 12, 2012 10:24 pm

Ok if you feel like having a tach to fill that empty hole, this might be the answer(maybe not, it's not back lit ).
You'll need a few things

Auto zone Sunpro tach (its the cheapest quality tach I could find)

A blank plate
A speedo needle
Those two screws from the speedo
This 4x6 photo printed from your favorite place (I went to Walgreens and got some extras).


So first off disassemble the tach. The face comes off by twisting it with some force counter clockwise and the back is held on by two screws. Now take the needle off. This is a little difficult, you have to sort of rock it and twist but it will come off. Now take the two little screws off for the face and remove the little brace that holds the face, and your left with the guts. Also remove the light, it won't do any good.




Take the blank and with some vice grips or pliers pull off the center nub from the back. You wont need it so just destroy it, no bigie. Now take the blank and set it face down on a flat piece of wood and slowly hammer down the hump with a rubber mallet. You want it flat but it doesn't need to be perfect.

Next take the guts and line up the hole wih the needle shaft then mark and drill the holes. I went with an angle so the ring screws wouldn't ground out on the guts. ( please disregard all the other holes, I was trying to make it back lit. It didn't pan out. Also the holes for the ring are drilled in this pic also)


Now take the ring and just eyeball the holes for the screws( if you want to be anal measure the screws on the idiot light pod) and transfer those holes to the blank. I over sized them on the blank and just used hot glue to secure them on the back

Now screw the guts to the blank and trim the back cover of the tach as much as you want( I went way too far) and screw it back on.

Now you might want a circle cutter for the face, I picked one up at a craft store for about $8. Practice a couple times to get the size just right, then cut the real one, test fit it , add the small hole for needle ,square it up in the blank and attach the ring with the screws (hot glue). As you can tell the face has been updated throughout the build, but I think my final came out flawless. Unfortunately for me I used one of the beta versions for my face. Feel free to edit or modify it. The color is close (real close) but not exact.

Don't put the needle on just yet. You need to calibrate it. I've got a tach/dwell meter( so should you) so I just hooked them both up on an idling motor and matched the meter. Make sure the tach is set to 4 cyl. Test it a bit by reving the engine a little and you should be good

A note on my needle... The damn thing is fragile! I broke it. but I had a cabriolet speedo needle that I was able to repair it with. So just a warning it's probably going to break. Also the face might fade, mine hasn't in the few weeks it's been in there, but it probably will eventually.

And that's it hook that puppy up and enjoy the uniformity of it all!

Philo Beddoe Sat May 12, 2012 10:32 pm

=D>

odecom5 Sun May 13, 2012 6:47 am

Great tutorial. Thanks!

Although the RPM is x100 in the one you printed (I see your template is now fixed though), hope it doesn't drive you mad, because it would me! :)

I never thought about doing it this way. I have a 3" tach that fits perfectly in the hole, just had to make a mounting bracket for it, works good, but I might steal this face and swap that out.

Thanks again.

donemoto Sun May 13, 2012 7:22 am

What is the wire hook-up for the tach? i.e. what wire goes where?

bugger101 Sun May 13, 2012 7:25 am

dam i have the same tach, now i know what i am doing with it :P

RocketSurgeon Sun May 13, 2012 7:33 am

odecom5 wrote: Great tutorial. Thanks!

Although the RPM is x100 in the one you printed (I see your template is now fixed though), hope it doesn't drive you mad, because it would me! :)

I never thought about doing it this way. I have a 3" tach that fits perfectly in the hole, just had to make a mounting bracket for it, works good, but I might steal this face and swap that out.

Thanks again.
It does drive me nuts, bu I was itching to get it in. I also flipped the 7 and 8.

RocketSurgeon Sun May 13, 2012 7:36 am

donemoto wrote: What is the wire hook-up for the tach? i.e. what wire goes where?
Black neg
Red switched power
Green to dizzy
White dash lights

markd89 Sun May 13, 2012 8:25 am

Awesome result. Thanks for making the write-up!

WestyMan1971 Sun May 13, 2012 8:51 am

This is excellent. Now I just gotta find a busted speedo to grab a needle from!

Stuartzickefoose Sun May 13, 2012 1:56 pm

Green actually goes to the negative side of the coil...to make life easier. ;)

bugger101 Sun May 13, 2012 4:54 pm

has now been added to the FAQ

RocketSurgeon Sun May 13, 2012 5:16 pm

bugger101 wrote: has now been added to the FAQ
Awesome!

donemoto Sun May 13, 2012 6:41 pm

Stuartzickefoose wrote: Green actually goes to the negative side of the coil...to make life easier. ;)

thanx

Jody '71 Mon May 14, 2012 6:50 am

The Sunpro Super Tach II's are great. I had one in my old '85 Cherokee for years. It never flawed. Unlike the VDO tachs that are out there now and have been so damned problematic during various production runs. If I ever decide to put a tach in my Bus it will be a Sunpro for sure. Oh and Stuart, you get another :D

Stuartzickefoose Mon May 14, 2012 11:21 am

2 points! \:D/

hippyvanman Sun Dec 30, 2012 5:11 pm

WOW. Great writeup!! I have 1 question though:
- did you have to shorten the needle at all to make it fit the smaller gauge size?

RocketSurgeon Sun Dec 30, 2012 10:17 pm

hippyvanman wrote: WOW. Great writeup!! I have 1 question though:
- did you have to shorten the needle at all to make it fit the smaller gauge size?
The original speedo needle broke but it would have needed to be trimed if it didn't. The replacement needle from a cabriolet tach was just right.

A little update; the photo face is fading and starting to curl. Soon I'll be replacing it with some sort of bumper sticker print on thin plastic. Haven't settled on it yet.

obnoxiousblue Sun Dec 30, 2012 10:28 pm

You should look to have it printed on UV resistant vinyl. When you do, have them leave extra material around the edges, if its a 3" diameter, have them leave 1/4" extra or so. That way you can gently pull it taught, and when you screw the assembly together there is material that can grab to keep it from pulling back in time.

Jus an idea.

hippyvanman Sat Jan 05, 2013 2:10 pm

Oh, and one more. In the picture of the finished product in the gauge cluster, it looks like you added some sort of glass in front to make it look like the rest, how did you do That?

chrisradioman Sat Jan 05, 2013 4:52 pm

Excellent work a good tip for removing needles is with 2 spoons, use them as a leaver. :D



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