cannot get the pump cap of my bosch wfl2260?

We are trying to clean the drain pump on our washing machine and cannot get the pump cap off. We have turned the cap approx 70 degrees anticlockwise but cannot pull the pump out. We are not sure whether the cap should be able to turn more than we have been able to or whther it is in the correct position to pull out. My husband has trying using various tools to pull it out and has only succeeded in cracking the handle that is used the pull it out. Any tips to avoid calling out a service engineer would be helpful?