I have a MF 35 1960 3 cyl perkins I totally rebuilt, started up and engine sounds great. I am getting blowby on all three combustion chamber caps. The old cap gaskets were circular, and the ones I replaced are shaped like the cap (copper). I took them off and put on new cap gaskets (shaped like the cap) and this time sprayed the copper gasket spray like you use on the head gaskets. I made sure it was all clean on the caps and the head, (surface and inside the hole). Torqued it all up to specs again and started, after about 30 seconds I got blowby on one and within a minute all 3 caps were getting blowby. Can anyone help me with this one, frustrating? thanks, John