Our 1963 in-city home has occasional sewer line blockages. Renting a power snake for $30/half day has gotten old. The city has scoped the line and suggest the constriction in diameter occurs 40 feet outside the house under a line of scrub trees holding a dramatic drop-off embankment in place to the city sidewalk, street & main sanitary sewerline. Because an iron pipe gas line runs adjacent to our sewer line, it appears it must be hand dug. I am hopeful that a 5 ft section of black ABS 4" pipe will replace the problem. Must I wait until Spring to dig? (It's Groundhog Day now.) How do I insert a five foot section into (between) rigid piping on either end? Will it require one or two rubber connection boots? How important is bedding that 5 ft on sand or pea gravel? How about fill above? I estimate the line to be about 2 feet below ground level. No room to get a backhoe nor "ditchwitch" to the site. Any tips welcome!
Loosen with a pick or mattock, move with a shovel, and be very careful of that gas line. Find the sewer line first from the side the gas line is not supposed to be on. 2 feet deep is easy.
If things are frozen now (I don't know where you are, since you didn't say) it will be more difficult to dig, but it can be done if needed. Otherwise wait for spring.
I'm not certain what the best approach to splicing the line in place would be. I'd guess 2 rubber couplers, because the still-buried pipe will not want to move. Mind you, at that age I'm also concerned with the distinct possibility that you might have 10 feet of cast iron and then change to Orangeburg (tar-paper) pipe, which is useless stuff by now (it ages poorly and age is upon it) and would involve digging up the whole run.
Bedding is important because otherwise that 5 feet can deform and interfere with correct flow in the pipe.