I have a two car garage built in the 1950's.
There are two floor drains under where each car sits to carry off salt, snow melt etc.
Each of these drains has a 15 inch cast iron cover over maybe a 30 inch deep sump that is about 12 inches wide--so the sumps can each hold about 10 gallons.
There is a four inch drain leading out of each sump-- the drain pickup is facing down and located about 2 feet down in the sump. the drain comes up vertically, then takes a 90 degree turn and exits the sump about one foot from the surface of the garage floor.
I cleaned out one of these sumps-- it had been draining slowly, and after I cleaned out about a five gallon pail of dirt-- the drain now runs great: I can run a hose full blast into the sump and it drains right out.
The other sump is full of an oily dirt mix- like sludge. I can clean this out with a liquid scoop, but this sump doesn't drain. I filled this sump with water to the surface of the garage floor-- and it drains VERY slowly-- like 2 inches an hour.
I tried a small snake but didn't get anywhere with that. I can bucket out all the sludge/water, but what's a good way to clear the mostly clogged drain? Would one of those "bladder"- type hose connected things be worth a try? I'm pretty sure the drain pipe is cast iron-- so pretty strong.
Thanks in advance for any suggestions.