The volunteers who restored the boat after raising it from the bottom of a lake successfully tested its engine in a loch on the Isle of Bute yesterday.
When Bluebird K7 flipped into the air and crashed on Coniston Water in the Lake District in January 1967, killing Campbell at the age of 45, it was racing at more than 300mph.
But its test run on Loch Fad was at a considerably lower speed yesterday. Project manager Bill Smith said: “It went very well – it worked first time out of the box.
“This project is 22 years old this year. We’ve been 15 years in the rebuild – five years to strip down, catalogue and clean, and ten years since we set the first rivet to bring her back to this condition.
“Every part has been cleaned and repaired. She looks absolutely beautiful now and she is how she should be.
“This is a fully working machine, completely original. This is the vehicle that Donald Campbell drove.
“We’ll be basically training ourselves on Loch Fad because no-one really knows how she will handle.
“Once this is done there’s always been the hope that she’ll be displayed at speed back in Cumbria.”
He added: “It’s half a century since anyone put her in the water then got her back out. No-one knows how she handles or the best way to jump out in a hurry if needs be.”
Mr Smith was inspired to recover and restore Bluebird K7 at his yard in Newcastle after hearing the Marillon track Out Of This World, an ode to Campbell’s bravery.
An attempt to refloat the craft earlier in the afternoon stalled when it became snagged on the beach of the loch.
Tim Walsh, the project’s lead pilot, added: “We are looking to assess how it copes with the water, are there any leaks and what challenge there is from different sizes of waves.”
The craft is set to undergo a battery of tests on Loch Fad over the coming weeks before it returns to Coniston next year, where it is expected to run at speed.
With his race suit still intact, Campbell was pulled from the Cumbrian lake with the wreckage in 2001.
Having broken eight world-speed records on water and land, he was trying to break his own water-speed record of 276mph when he was killed.
Campbell, the son of speed record-breaker Sir Malcolm Campbell, was posthumously awarded the Queen’s commendation for brave conduct.