Washer/plumbing advice

[Daniel Alegre]

So last week my tenant let me know her washer was not draining so I checked it out and it looks like the old iron drain line is clogged. So I decided to just simply drain right into the sum pump. 

Now the washer is getting stuck on wash cycle and not doing anything.  I noticed that during the sensing portion of the cycle that water was draing into the sum pump. What I think is happening is that since the drain hose is not going up then down into a drain that water level in the machine is not being met and the cycle doesn't start. I thought that the drain had a stop vavle and a pump, I guess that's not the case. 

I wanted some advice before I go call a repair man or try to replace the iron drain pipes worth PVC. Does it sound like my reasoning is correct and I should replace the pipes or does it sound like a Washer problem and I should call a repair man?