Originally Posted By: Brian Barnhart
Originally Posted By: 901Memphis
I don't believe a cut open picture of the ADBV is valid since the leaf spring pressing the end cap into the valve will make it fit tighter and probably seal a lot better.
This is a good point, and I should have mentioned it. The force of the leaf spring will seal a poorly positioned ADBV to a greater degree than shown in my picture. I was illustrating a possible source (leaking ADBV) of the start-up noise I have experienced at times with Fram Extra Guard filters.
The source of the start-up noise could have been due to a different issue. Whatever the cause, it was reduced or eliminated by changing oil filters.
Brian,
ADBV's are tested for leak rate on a calibrated test stand. It does not matter what the design is as long as they meet SAE and ISO standards for leakage and we do. If you "hear a start up rattle" it means one of two things, the filter has been on the car long enough for the ADBV to become brittle (silicone is best for longer OCI's) or there is a piece of [censored] stuck under the valve letting it leak.
Originally Posted By: 901Memphis
I don't believe a cut open picture of the ADBV is valid since the leaf spring pressing the end cap into the valve will make it fit tighter and probably seal a lot better.
This is a good point, and I should have mentioned it. The force of the leaf spring will seal a poorly positioned ADBV to a greater degree than shown in my picture. I was illustrating a possible source (leaking ADBV) of the start-up noise I have experienced at times with Fram Extra Guard filters.
The source of the start-up noise could have been due to a different issue. Whatever the cause, it was reduced or eliminated by changing oil filters.
Brian,
ADBV's are tested for leak rate on a calibrated test stand. It does not matter what the design is as long as they meet SAE and ISO standards for leakage and we do. If you "hear a start up rattle" it means one of two things, the filter has been on the car long enough for the ADBV to become brittle (silicone is best for longer OCI's) or there is a piece of [censored] stuck under the valve letting it leak.