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> Tach bounce, How to fix it, if you can
porsche735
post May 1 2003, 01:17 PM
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My tach bounces all over the place. Since only 1 wire connects it to the coil and it is grounded near the dash, seems like the bounce is internal. Does anyone know how to fix this? Is there some capacitor or something that may have blown? Seems like it should be something simple to fix....
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Lawrence
post May 1 2003, 01:25 PM
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Clean and adjust points. Clean wiring connections to/from tach, coil and dizzy. Clean grounds.

That should get most of your bouncing taken care of.

-Rusty
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Evill Ed
post May 1 2003, 01:36 PM
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The 914 tachs did this. Some later units had a damper added to eliminate the bounce.

Personally, I found an Autometer Monster tach fit the stock dash hole and looks a whole lot cooler. And it doesn't bounce.

Ed
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porsche735
post May 1 2003, 01:36 PM
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I just went through every inch of the wiring harness for another problem. Everything is clean and has a good ground. What is the next step?

Thanks,
Chris
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porsche735
post May 1 2003, 01:37 PM
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Was the damper mechanical or electrical? There must be someone who has fixed this? No?

Chris
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Evill Ed
post May 1 2003, 01:42 PM
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The damper was in the tach and I think it was mechanical. Either find a good used tach with the damper or try one of the rebuilders. ( I can't recall the names) North Hollywood Speedometer maybe?

Ed
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Anton
post May 1 2003, 02:22 PM
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Chris,

I agree with your line of thinking that a condenser parallel to the gauge itself might attenuate the bouncing of the needle (and slow the upward movement). Cleaning the wires or points will have nothing to do with it. You could open the tach to see if a condenser is present. Better yet, ask someone who revises tachs.

On the other hand, these little inconveniences are part of the charm of 30 year old cars. (IMG:style_emoticons/default/wink.gif)

Anton
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Anton
post May 1 2003, 02:42 PM
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QUOTE(porsche735 @ May 1 2003, 11:17 AM)
Ich habe einen Schnauzer in meinen Hosen

Mmm, quite remarkable to read that you have a LITTLE German dog in your pants, cause that's what a Schauzer is. (IMG:style_emoticons/default/lol2.gif)
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SirAndy
post May 1 2003, 02:54 PM
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QUOTE(porsche735 @ May 1 2003, 12:17 PM)
My tach bounces all over the place. Since only 1 wire connects it to the coil and it is grounded near the dash, seems like the bounce is internal. Does anyone know how to fix this? Is there some capacitor or something that may have blown? Seems like it should be something simple to fix....

i had the same problem and it turned out to be a cracked relay-board. what shape is your relay-borad in? take it out and look at the bottom, if the material is all cracked and you can see the metal inside, it might be time to replace.
worked for me (IMG:style_emoticons/default/cool.gif)

Andy
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SirAndy
post May 1 2003, 02:56 PM
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QUOTE(Anton @ May 1 2003, 01:42 PM)
QUOTE(porsche735 @ May 1 2003, 11:17 AM)
Ich habe einen Schnauzer in meinen Hosen

Mmm, quite remarkable to read that you have a LITTLE German dog in your pants, cause that's what a Schauzer is. (IMG:style_emoticons/default/lol2.gif)

could be a "mustache" too. either way, it's kind of "unusual" (IMG:style_emoticons/default/wink.gif)

Andy
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krk
post May 1 2003, 03:46 PM
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QUOTE(SirAndy @ May 1 2003, 12:56 PM)
QUOTE(Anton @ May 1 2003, 01:42 PM)
QUOTE(porsche735 @ May 1 2003, 11:17 AM)
Ich habe einen Schnauzer in meinen Hosen

Mmm, quite remarkable to read that you have a LITTLE German dog in your pants, cause that's what a Schauzer is. (IMG:style_emoticons/default/lol2.gif)

could be a "mustache" too. either way, it's kind of "unusual" (IMG:style_emoticons/default/wink.gif)

Andy

Schuauzers come in three sizes -- Miniature, Standard and Giant.

The most common is the Mini, the least common is the Giant, and the *best* is the Standard. 20" at the shoulder, 45lbs or so, terrier-tenatious and loyal as heck.

(man, this is straying far OT, eh? Oh well -- mid afternoon break :-))

kim.
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porsche735
post May 1 2003, 05:53 PM
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Yes, I do have a wiener dog in my pants.... Finally a proper translation....

By the way, the relay board is new and has been thoroughly checked. The connection has been traced all the way from the tach to the coil and it looks good. Seems like the problem is in the tach itself....

Chris
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Mark Henry
post May 1 2003, 06:04 PM
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QUOTE(Evill Ed @ May 1 2003, 11:36 AM)
The 914 tachs did this. Some later units had a damper added to eliminate the bounce.

Personally, I found an Autometer Monster tach fit the stock dash hole and looks a whole lot cooler. And it doesn't bounce.

Ed

The Autometer tach's are suppose to be way more accurate at high RPM's. I have one, off of a bug I bought, that I want to install in mine.

Ed how did you attach (fix) it to the panel? The factory rubber might work, it's a bit tight, also it makes it stick out more. Or did you just silly-cone it in.

(IMG:style_emoticons/default/MDB2.gif)
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Jeff Krieger
post May 1 2003, 09:28 PM
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QUOTE(Evill Ed @ May 1 2003, 12:36 PM)
The 914 tachs did this. Some later units had a damper added to eliminate the bounce.

Personally, I found an Autometer Monster tach fit the stock dash hole and looks a whole lot cooler. And it doesn't bounce.

Ed


Ed, where did you buy the Autometer tach? Can you post a picture of it installed?
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