No idea... might be best to try a GTO site... is that an original tach? does it work with modern ignition? I was going to look into the repro one of these days...
Yes, you can take them apart, but not too many times. The pot metal is basically crimped around the lens. There are a few pieces that are held together by the pressure of the crimped shell, so be prepared for that. Otherwise, absolutely it can be done.
If you want to just clean the lens why not use the polish that they
use for headlights or NOVUS PLASTIC POLISH. This is something that a
plexiglass guy turned me onto years ago.
Not sure what you are trying to accomplish? If you're looking to replace the lens, you're there. My understanding is that the factory tach won't work on the HEI, but the reproductions do.
PS. That little white blob on the back of the needle that looks like wax... that ain't wax. Don't try hearing it to remove it as the larger black piece will melt first.
Not sure what you are trying to accomplish? If you're looking to replace the lens, you're there. My understanding is that the factory tach won't work on the HEI, but the reproductions do.
OK. Now I get it.
If I recall correctly the knob does not come off. That little pieces of hardened plastic/glue that is secured to the black butterfly is what needs to come off (but don't use a heat gun). Once that's off, you should be golden.
A lot of '60's GM's had a small set screw that went through the knob and tightened against the shaft. Use a small, flat jeweler's or optical screw driver. Not sure if this one is the same or not.
That blob is simply cast pot metal (part of the knob on the front) they press it together with the needle in place with a vice type tool (that's why you see the imprint on it) if you carefully remove material from that, the knob will come out. Pay attention to how it is put together. Most have a spring washer and a paper washer. Once you have it apart, you can do a few things to put it together, You can carefully hammer to fold the remaining material over to hold everything back together. You can use a combo of the previous with some epoxy, or you can do as 66 states and use a set screw, but you will have to drill the back post of the knob.
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63 Grand Prix -needs restoration, 65 Catalina Ventura 4 speed - resto almost completed, 66 Catalina Convertible - at body shop
That blob is simply cast pot metal (part of the knob on the front) they press it together with the needle in place with a vice type tool (that's why you see the imprint on it) if you carefully remove material from that, the knob will come out. Pay attention to how it is put together. Most have a spring washer and a paper washer. Once you have it apart, you can do a few things to put it together, You can carefully hammer to fold the remaining material over to hold everything back together. You can use a combo of the previous with some epoxy, or you can do as 66 states and use a set screw, but you will have to drill the back post of the knob.
Please forgive me for the questions. Just to confirm what you are saying, when you say blob and remove material are you meaning where the arrow is on the pic?
-- Edited by pudge444 on Saturday 16th of September 2017 12:02:35 PM
Don't know if this will help you Kevin with your tach knob, because this relates to my experience with similar looking knobs on clocks.
On my 1963 Pontiac the knob on the clock is threaded and to remove you need to hold the stem and turn the knob
counter clockwise to remove it.
Another style is (as mentioned earlier in the thread) is a small flat head screw in the center of the knob that has to be removed to take the knob off.
I'm thinking if you have a what looks like glue at the top of your knob,someone has lost the small set screw and has filled it with glue to secure the knob.
I don't recall ever seeing glue being used with these small knobs......but they may have.
Anyway here are some pictures of the knobs I'm familiar with.....I'm sure there must be a member with the same tach you have that could advise
you better to how the tach knob comes off. hope this may help you somewhat.
I got it apart. I ended up grinding out the solder or what ever it was that was part of the where the indicator was attached. When I put it back together I'll either JB, or solder it.