The most common and most likely answer to this crossword clue is the 7 letter word GREMLIN
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More clues leading to the result GREMLIN
- Zip-join coming up short? This could cause trouble
- Troublemaker good to replace leader in citadel
- Foreign government gets new leader, a trouble-maker
- Grand government's ousting top troublemakers
- Spirit causing problem — about millilitre in drink
- Troublemaker in Russian government wanting new leader
- Carelessly malinger without a reason for machine’s downtime
- Troublemaker ultimately crowing having supplanted king in citadel
- Gross Welshman, reportedly a troublemaker
- Bug government elite in Russia that’s faceless
Buddy explains!

The straight part
We know that "reason for machine’s downtime" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case reason for machine’s downtime = gremlin.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does GREMLIN mean?
GREMLIN noun- A mythical creature reputed to be mischievously inclined to damage or dismantle machinery.
- (by extension) Any mysterious, unknown source of trouble or mischief.
- A young inexperienced surfer.