Talked to Mercury Marine today and they told me the poppet balls have to stay on this motor. They told me that they help keep the motor at right operating temp. so it performs well. I'm not sure I agree with them. A lot of the motors I have seen have just the two large lines and the two lines that go to the manifolds. Just hate to put out the cash for that type and have a problem. Anybody ever tried this type on this older motor?