I'm looking to identify a movie title that I saw when I was very
young.  It would've been around mid 1980's, and could be a made-for-TV
movie.  It was a family adventure time-travel movie about a kid who's
grandfather builds a time machine and he travels back in time to the
early-mid 1900's.  It was so long ago that I only remember two
details:

- The time machine was a metal framed pod (no outer shell) that fit
one person.  It had old-style rotary numbers on it to show the date
and spun around very fast on a vertical axis when active.

- When the kid travels back in time towards the beginning of a movie,
he walks by a gas station where one numbers for the gas prices has
fallen down.  The owner asks him to put the sign back up, but the kid
incorrectly prices it because gas was much cheaper back then.  Cars
drive by for gas but keep going when the see the high price the kid
has put up.

I've done some extensive searching on IMDB with no luck.  The movie
had a Disney feel to it, but was real-life (not animated).  I've been
through Disney's library too but fear that it was in fact a
made-for-TV movie that is harder to find.

Hello.

It sounds like you're describing a Disney made-for-TV movie called
"The Blue Yonder" (1985), also known as "Time Flyer."

From the Internet Movie Database:

"Excellent TV movie for all ages. Peter Coyote, Art Carney, and
Huckleberry Fox are wonderful in this movie. A young boy hears about
his great grandfather trying to fly across the English Channel from
stories by his grandfather. Then he finds out his grandfather has a
time machine he has been too sick to use. Max takes it for a spin and
meets his great grandfather in person. He tries to help him make the
flight that could put him in history books."
http://www.imdb.com/title/tt0088831/

From PeterCoyote.com:

"The tale is about 11-year-old Jonathan Knicks (Huckleberry Fox) and
his trip back to the year 1927 and the hero grandfather he never knew.
As inventions go, his time machine isn't as cute as the flying car in
Chitty Chitty Bang Bang. It's just a bunch of gears and wires that
spin him around like wet wash in a dryer. Then, presto, it's 59 years
ago..."
http://www.petercoyote.com/yonder.html

"The Blue Yonder" VHS at Amazon.com:
http://www.amazon.com/gp/product/B000683DK0/

-------------
search strategy:
"grandfather * * time machine" movie

I hope "The Blue Yonder" is the movie that you had in mind.  If not,
please let me know via the "request clarification" feature.

Quick and comprehensive answer, exactly what I was looking for.

Thank you for the tip.
-juggler