Not sure if this is the correct sub-forum to post this but figured I'd give it a whirl. I tried using my MityVac 7400 yesterday to drain my motor oil. I did everything like I normally do but this time I wasn't drawing a vacuum as I pumped the handle. Instead, some oil that remained in the body after my last oil change was being pumped up and leaked out from under the handle, making a huge mess on my garage floor. I don't know what went wrong or what to do. Is this user-error or has my MityVac stopped working after only 4 or 5 uses? Has this happened to anyone else? Thanks!