I think you need to research a bit more, wasn't that hard to find. And while I don't like primates at all I understand the curiosity so I found this for you. It is from Gould, K.G., Young, L.G., Smithwick, E.B. and Phythyon, S.R. (1993), Semen characteristics of the adult male chimpanzee (Pan troglodytes). Am. J. Primatol., 29: 221-232.
So about 4ml not very different from humans in volume but a lot more sperm.