Tachometer failure

[Steve Ahrens]

Weather conditions were perfect today for committing aviation in the Skinny Bird. Until the tacho went out to lunch!

Checking the cable down at the drive on the back of the engine, I found I couldn’t turn the cable with my fingers. After some fancy contortionist manoeuvres I managed to remove the tacho from the instrument panel. The tacho is held in place with 3 screw clamps, one screw being positioned at about 1 o’clock, I don’t know how I’ll get that one back in.

The tacho is very firm to turn, and I think it’s very fortunate that the cable didn’t brake.

[Andy Gelston]

I don't recall my Porterfield tach having a mounting like that! That's pretty Rube Goldberg, but just reminds us that a lot of cobbling can happen over eight decades. Fortunately, we have many of the factory drawings available so we can restore our old gals to very close to original. For instance, the mag switch on the panel isn't factory. The toggle switches were located up over your left shoulder, on a plate with two holes in it.

I sent my tach out to Keystone for calibration, etc. as part of 41VT's restoration.

[Steve Ahrens]

Tacho failure update.

The drive gears in the angle drive have worn out, hence the reason for the tacho to cease operation.

Obtaining any parts or even a tacho in Australia is proving difficult. I’ve found an angle drive on ebay, P-65535, but I would also need the main drive shaft with the bevel gear on the back.

Is there anyone hear that has a surplus tacho or know of anything?

Andy, do you have a contact for Keystone?

Thank you in advance.

[Andy Gelston]

Gadzooks, that's worn! Keystone's website is: http://keystoneinstruments.com/