The Divrei Shaul (Yoreh Deah 358) writes: “Some say that if one hasn’t been to the kever of his father for many years, some say 7 and some 10, he should no longer go. I laugh at this custom as we see that Calev went to daven by kivrei Avos, even though he hadn’t been there for many years”.
He concludes that there is nothing wrong with going, even if one hasn’t been for many years.
The Shu”t Hisorarus Teshuvah (Yoreh Deah 187) also writes that he never heard of such a custom and we don’t find it in the poskim.
The Shu”t Shem MeShimon (Orach Chaim 4) cites a Zohar. The Zohar (Shemos pg. 16) relates: Lachma bar Livoy wasn’t by his father’s kever for 12 years, he then went and when his father realized he had come, he was overjoyed to see him” We see clearly, that even if one hasn’t been to his father’s kever for 12 years, there is nothing wrong with going.
The Otzer Yad Chaim (278 and others Achronim) argues on the proof from Calev. Perhaps the aforementioned custom is specifically by a parent. Calev, however, wasn’t going to his father or mother, he was going to the holy Avos, and it may well be that they are different.
The Otzer Yad Chaim writes, that the Divrei Chaim of Sanz was very particular about the above, and so was the Belzer Rebbe.
The Shu”t Divrei Yatziv (Yoreh Deah 245) writes: The Divrei Chaim of Sanz wasn’t able to go to his father kever for a number of years, and after that he was careful not to go. Therefore, one shouldn’t be careful about the above, even if there are kevorim of other family members nearby.
The Shu”t Afraktsa D’Anya (Vol. 1, 168) writes: If one never went due to circumstances beyond his control, i.e. he was a captive or some other reason, there is nothing wrong with going, even if one hasn’t been for many years.
Another answer to why Calev may have been different, is that perhaps the above only applies if one was accustomed to visiting his parents kever and then he stopped. If one never went altogether perhaps it’s different. Calev, went to kivrei Avos for the first time.
Another answer may be, by kevorim of parents, if a son doesn’t go for many years, it’s likely that no one else has gone either. Consequently, it could be that the niftar gets very angry, and may decide to harm a son after he decides to finally return after many years. By the Avos, however, its illogical that no one went to daven by them for many years, therefore, it was ok for Calev to go and daven there.
