I think if someone is making money off your work, and remember your snaps are your property, without your permission then you have a right to complain. But, as Adrian says, is it worth the effort? In his case I agree, whereas in mine, I would be aggressive about protecting my copyright. It's a question of being asked. As said, things freely available on the web tend to slip into the public domain, but this is no defence in copyright law if pushed. Theft is theft. It is down to the owner to push as far as they want.
Adrian has achieved the right balance in his case. However, if a progressive set of snaps of a rebuild were lifted for a book and presented in a way which gave the impression they had been done for it, then I would pounce. No harm in getting some ££ when it is due.
This is not the case if it is a snap of your motor taken by someone else, but how nice that the model maker sent Bernard an example. That is really good PR and proper manners.