jumpy tac?

Hey guys. After winding out on some twisties today I noticed my tac started humming and jumping about 2k below where it should be and back to its proper reading. It almost sounds like a spun bearing? New cable btw. Can it be dissasembled and cleaned n greased easily?

 

Yes.

No, but easier than mine is to lube.

My Seca cans are different than the Maxim cans, so I'll let someone else elaborate on the specifics of those particular instruments, but here is a rundown of the basic procedure:

bigfitz52's instrument write up

 

The link above is for the 550 Seca and how to get to the instruments, I forgot that post was a two-parter.

Here's what to lube once you get in there:

Instrument disection

 

Thanks. The vibration broke the needle today.. oops. wonder if I should replace the whole lot. Or fix what I've got?.

 

Price out new clusters, the age of these gauges make them very brittle. Don't ask me how I know.

Long story short;
I'm running an Acewell because I tried to change my tach needle.

 

The needle can be repaired. Flat toothpick, superglue and epoxy. Either rebuild the needle, using the toothpick to support the underside, or use the toothpick as replacement and paint it.

 

:lol:
et opiniones sicut anuses, unus quisque evaderet

 

Here's the technique for "The Toothpick Method" I wrote-up some years ago.

You can fix it ... you just need to put your Precision Hat on.
Mask the face of the Speedo off with some Aluminum Foil followed by some Paper towel.
Get some 5-Minute Epoxy.
Epoxy a Tooth Pick to the underside of the fragment.
Just to the butt-end and hold it perfectly straight until the Epoxy cures and the Tooth Pick becomes part of the former indicator that broke-off.

Next.
Mix a SMALL amount of Epoxy and use another Tooth Pick to "Coat" the glued-on Toothpick.
Build-up a nice "Bead" of Epoxy from the break to the tip of the glued-on Tooth Pick.
Cover the repair with a coat that will built-up and form the new Speedo Needle.

While the repair bead is almost cured and still a little bit flexible ... nip-off the end with a pair of fingernail clippers to the correct length.
Leave it alone after using a Razor Blade to remove any Epoxy that starts to drip-off and fall on to the paper towel.
In other words ... clean-up and "Shape" the underside ... flat.

When it's done getting cured ... do a final shaping and "Roughing-up" of the surface with a brand new Emery Board. Your wife should have plenty.

Once you have finally shaped and lightly sanded the surface ... paint it.

get the paint from the "Testors" (Trademark Brand) Paint Rack at a Hobby Shop.
The matching Red is: "Italian Red"
An alternative Needle indicator color is: Florescent Yellow.

While you are at the Hobby Shop; pick-up a tiny paint brush (Artist type) to use putting-on the paint over the repair job.

Don't try to get the repaired Needle painted all in one sitting.
Apply a first coat.
Let completely dry.
Emery board out any "Pulls or wrinkles"
Apply second coat.
The second coat might do the trick.

If it needs a third coat ... wait for the second coat to dry.

New Speedo Needle Indicator.
Cost: 10 Bucks or so!

Change the Bulb colors to anything that is available with pre-colored bulbs.
Red, Blue and Orange are nice.

Take your time and do a nice job.
Wibe the Bulb Holders with a Q-Tip soaked in Armoral.

PS: A two-tone Indicator with the tip painted a different color than the needle body is trick.
Use some 3M Vinyl Masking tape to mash-off the Red Line area of the tach and add some color to the tach.

 

Brilliant. Pure brilliant. Im assuming any extra added weight by the tooth pick won't effect things?__

 

Umm...

 

Lol stupid question ehh?

 

The repaired needle will be slightly heavier, but shouldn't effect the accuracy of the tach too much. Consistency is what you're after. If you're really concerned you could borrow an inductive tach from an auto parts store and compare readings