Could not name the movie. Involves drilling into the earth crust but ended up somewhere else

I recall when I was young (in the late 1980's) I saw a snippet of this movie in full-colour, but I can not remember the entire film nor the title.

Now I am older, I wish to know what the movie was about and understand it more. Here is all I know about the film:

It was an action movie.
It is like the latest movie "The Core" which has several people inside a larger drilling machine in the earth. I suspect there was sabotage or some effect from the drilling machine that knocked the driver out and it affected his path of digging into the earth. I recall seeing a dashboard next the driver showing multi-coloured layers which showed the current location where it was at.
It was a colour featured film.
I don't know if there were dinosaurs or large creatures etc.
More like the in the spirit of Journey to the Centre of the Earth but not a lot of walking at all.

Hope someone can assist me here.