Hoot, I did not rubber mount mine. I decided to run it the way it was and wait for the fuel test results. I was not concerned with mounting it on the engine because that is where most big rigs have theirs. Most heavy equipment, portable and stationary generators, to name a few, have the filters mounted on the engine. I asked Racor if there was a problem with the engine mount. They sent back a one sentence answer. They said: We do not recommend engine mounting do to the clogging factor. Dah! I asked them to elaborate but did not get a response. Later!