Be careful of fuel pressure ( 5 bar is 5 x 14 PSI ) if pump is running and you have no fuel in either of those two lines,the filter is blocked,if you have changed the filter (which must be done at least annually) then the fuel pump check valve is seized( it's in the nipple that fuel outlet line on the pump is located).If you have fuel,get an assistant to turn the engine over with the igniton while you gently push the large disc in the fuel distributor down.This will allow an overich mixture to be injected .if the car starts you have either a fuel pressure problem( sick pump or pressure accumualtor) or the fuel dstributor spindle valve is sticking ,something which is not unusual in a car that has'nt seen much use.
Do not use the acelerator when trying to start any mercedes.
that device in your pic is the fuel cooling line ,it cools the fuel in hot weather by runnning it over the suction line in the AC system.It's to prevent vapour lock in warm climates..Florida right?