If we're talking about one event which happened in the past and no specific time was mentioned at the beginning, but later we say when it happened, should we still use present perfect tense until we mention when it happened?

Also, as I understand, present perfect tense can be used if something what happened in the past has some connection with the present. So if we have a sentence like this, "I know a guy who has crashed his boat into a tree". I'm not saying when he did it, and the time is actually not important. Isn't it suggests a listener that the boat is still wrecked? If so, so it means that I should just say, "I know a guy who crashed his boat into a tree".?

It doesn't matter if the boat is fixed or not, but I want to understand how it sounds to a listener. I think I understand present perfect tense correctly (almost), but still not sure about things like I mentioned above. If something was/has been crashed/wrecked in the past and if I'm speaking about it after a long time, isn't using present perfect tense suggests that those things are still wrecked?