When i visited there was a tour at 11 am, 12 and 1 pm😉
On weekends, engine room tours run every hour beginning at 11:00AM to 3:00PM depending docent availability. The docents (museum tour guides) are all volunteers and through infrequent, there may not be enough available to conduct tours every hour. During the week engine room tours will run on the same schedule depending on visitors aboard.
The time schedule might have changed, my suggestion is to check the website for it, I will try to get back at this question with the link if I can.
I don't remember exactly what the times are but I think it's 3 or 4 times a day. They will tell you about it when you get to the information booth.
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