308 QV Tach glass | FerrariChat

308 QV Tach glass

Discussion in 'Technical Q&A' started by Quasimotor, Jan 5, 2004.

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  1. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    I have a crack across the glass in my tachometer. How do I get the old glass out so I can have a new one made up? I tried turning the bezel from within the cockpit, and it went counter clockwise (which now looks cockeyed), but won't go clockwise and won't come off.

    I'm stuck with a cockeyed tach and a cracked glass?

    Do I have to get the tach out from behind? How do you do this?

    Thank you in advance for your help.
     
  2. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,913
    USA
    There should be a lot of information in the archives about removal of the gauges. Here it is in a nutshell:

    Remove each of the four indicator lights in each corner of the binnacle.
    Behind each light is a #2 Philllips screw, remove this.

    Place a towel across the steering wheel area to protect from scratches.

    Pull the faceplate out.

    Behind you will find two thumb screws that retain a metal clamp that holds each instrument in place. There will also be a large Molex type plug

    The ring that retains the glass on the instrument looks very hard to remove. It would probably require some careful bending of tabs around the edge to remove, and reinstall. You may want to have a speedometer shop perform this service, since if you mess up the metal trim ring, it is doubtful you can get a replacement, you would probably have to replace the entire gauge.
     
  3. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Thanks! Does the Molex plug provide a connection for several guages in the cluster or is there a separate one for the tach? Does anyone have any photos of this?
     
  4. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,913
    USA
    No photos...should be an individual plug for each instrument, if I remember correctly.
     
  5. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    To remove the trim ring in my 328, I used a plastic scraper to pry it back then I worked my way around the ring with the scraper and to hold it open, I put 1/4" wide slices of plastic (credit card type of material) every inch or so. It is much like taking a bicycle tire off the rim.
    Although a bit time consuming, the case is plastic and the ring is very flexible so it is not a very difficult job.
    I still have it out so If you want I could post or email you some pictures.

    Mark :)
     
  6. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Mark,

    Thanks for the offer. That would be helpful. You've given me the encouragement I need to try this.
     
  7. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    #7 Mark 328, Jan 7, 2004
    Last edited by a moderator: Sep 7, 2017
    Attached are a few pictures of the tach and the plug.
    I encourage you to do it--it is not too difficult.
    The main thing to watch out for is to be careful not to distort the bezel ring when you are prying it off & on.
    The glass is .080" thick and 3.960" Dia.

    Mark
    Image Unavailable, Please Login
     
  8. Mark 328

    Mark 328 Formula Junior

    Nov 6, 2003
    510
    Orange, Ca
    Full Name:
    Mark Foley
    #8 Mark 328, Jan 7, 2004
    Last edited by a moderator: Sep 7, 2017
  9. jmillard308

    jmillard308 F1 Veteran
    Owner Silver Subscribed

    May 29, 2003
    6,568
    Perth West Oz
    Full Name:
    John Millard
    Insert: Remove Steering wheel
     
  10. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,913
    USA
    Yes, removing the steering wheel will greatly improve access, but I would try to avoid it if you can. (I have a extension peice, that adds 1.25" so it clears). It can be difficult to remove the wheel, as the 3mm Allen screws are installed with Loctite, and you need a good quality Allen wrench, and even so, it is possible to bugger up the screws. I had one that was very tough to remove, and ended up having to drill a hole in it, and use a screw extractor to get it out.
     
  11. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    This is really good. I think I'm ready to get going on it. Thanks everyone. BTW, what do you mean Dave, about a 1.25" extension piece? What is extended, the tool, the tach, the panel???
     
  12. f355spider

    f355spider F1 World Champ
    Owner Rossa Subscribed

    May 29, 2001
    17,913
    USA
    Sorry, for my crappy description, it is a steering wheel extension, so I don't have to reach out for the wheel as much. I have 32" arms, and the car seems designed for one one with 35" arms in mind.

    They sell them at www.ogracing.com....but you will need a horn button adapter from Momo, and those seem to be awful hard to come by these days.
     
  13. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Okay, I started to get down to this job tonight, only the panel on my car doesn't match all your descriptions - or else I'm just not seeing it.

    Here are two photos of my panel. I've pulled out the battery light and like a normal light, it's got a bulb and socket behind it, but no screws. Where's the screws??? Please help, if possible, with photos of your own panel and where the screws are. F parts book is no help either.

    Thanks again,

    Quasi
     
  14. brent Lachelt

    brent Lachelt Formula 3
    Silver Subscribed

    Dec 6, 2003
    1,828
    Brownsburg, INDIANA
    Full Name:
    Brent R.Lachelt
    They are there. About 3 or 4 inches back from those access holes where the lights are removed. If you get a little flashlight you can see them. As I recall there are 4 phillips screws one behind each light that holds the face plate on.

    Good Luck
     
  15. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Thanks everybody! I got to the screws (there were only two - one a short ss self tapping, one a long machine screw) and with the wheel off, it came away easily. Took out the tach and following your advices, carefully pried off the chrome rim to release the glass. There seems to be a thin, rubber gasket behind the glass - it doesn't seem to fit quite large enough for the hole. What have you guys done with it? I found that by using about 8 small flat jeweler's screwdrivers, I was able to gently stretch the ring so it popped off. How do you get it back on!!

    Well, saturday I'm off the the glass guy to cut me a new one and then back to reassembly.

    Thanks again!
     
  16. doubleoh7

    doubleoh7 Guest

    Jan 20, 2004
    2
    I am realizing the post I just made on my 328 is v. similar. Did you figure out how to get the black bezel ring back on? Mine is still mounted in the dash - i've been hoping I wouldn't have to remove it all just to get the ring back on..
     
  17. Eric308gtsiqv

    Eric308gtsiqv Formula 3

    Nov 26, 2001
    1,955
    Orange Park, Florida
    Full Name:
    Eric Eiland
    Getting the ring back on (with the rubber o-ring) is the hardest part. It can be "worked" back on with the aid of a wooden popsicle stick (or other very soft but firm flat tool) so as to not scratch or damage the ring (esp. the chromed ones).

    I removed the speedo lens on mine a couple of years back to clean the backside of the lens (with the steering wheel and speedo / dash still in place), and it was next to nearly impossible to get the ring / o-ring / glass / and inner plastic housing back on. I'd get one side started and the other side would pop out. I ended up temporarily "gluing" it back on until I have time to pull everything and do the job right. For now, it's not going anywhere so I'm not worried about it :).
     
  18. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Okay guys, I have done this and it is very hard. Probably there is a special tool for this, but here is what I did (after breaking the glass once). You'll notice that the front face of the body of the tach/spedo is slightly tapered toward the front-center of the circle, suggesting that this is a press-into kind of fitting. I gently sanded the outer edge of this circle to make the diameter just slightly smaller. You'll also notice that the chrome retainer ring (the only part that shows on the outside of the instrument pane in a 308) has a notch on the inner rim, which allows you to screw this, first over the black inside retainer rim (which holds the gasket and glass). I gently turned up one of the inside lips of this notch to create an angled "thread." It was easy to screw in the black retainer ring and set the glass into place. The hard part, of course, is getting this all onto the white body without breaking the glass. The next step was to screw the white body into the chrome ring. I used one of those devices used for removing jar lids and oil filters (it's made of a plastic handle and a long, rubber strap - you wrapt the strap around the chrome ring and then use the handle to lever a rotation around the white body). Eventually, you will get most of the ring around the white body. The remaining part is the tricky part. Place this face down on the edge of a table and apply careful but firm pressure downward, forcing the "arrow" face of the white body down into the ring. Be careful to allign the chrome ring and not the black plastic ring to the surface of the table. With just the right force, you will hear a plastic (not glass) snap and the white body will snap down into the ring. You may have to rotate the body a few degrees and repeat to get the whole ring down. Then, with a SMOOTH vice grip (or one with cardboard inserts on the rough bit edges) press back into place the rear ring edge that you pried up to make the screw lip as described above. I had a smooth vice grips and did this only to discover I had switched vice grips to a rough one and marred the ring, but that is something I will now live with.
    I hope this helps someone. It's really a *****, but worth it.

    Quasimotor
     
  19. yelcab

    yelcab F1 World Champ
    Consultant

    Nov 29, 2001
    12,661
    San Carlos, CA
    Full Name:
    Mitchell Le
    My GT4, the speedo was so crappily designed and manufactured, the ring slips on and off merely by a thought. Terrible engineering.
     
  20. xe1yfj

    xe1yfj Rookie

    Mar 18, 2012
    3
    Mexico City
    Full Name:
    Javier
    Mark:

    Can you send me the pics of how you pull out the speedo body of the ring?

    My mail is [email protected]

    Thank you.

    xe1yfj
     
  21. Quasimotor

    Quasimotor Formula Junior

    Jan 4, 2004
    325
    Yonkers, NY
    Full Name:
    George Avgerakis
    Boy, that was a long time ago - can't remember. As I recall vaguely, you go back behind the unit and unscrew something there and then pull it out the front. Once out, I think you gently pry off the ring. The glass is a common window glass that you can have cut at any window store. Please verify the above as I am not certain. I do recall some major fiddling to get the ring on or off, but eventually it worked out. Be patient in any case, especially when rebuilding. In fact, order two pieces of glass.
     

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