Do we need to use the past tense of there is?
He explained that I had to carry on along the road towards Portsmouth, until I got down a steep hill, then to take the turning to the left at the bottom of the hill - He said there's a pub called The Green Man on the right just before the turning...
If I were a native speaker of English, I would never shut up. :-)
If the pub is still there or we expect it to still be there, I would stick with the present tense. You could say "He said there was a pub called ..." but you're reporting what he actually said. His words were spoken in the past but he no doubt said "There is a pub called The Green Man ...".
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.