Fred, The Safeguard Sentinel "sensor" is really just a plain old oil pressure switch. There's a special socket designed for removing/installing the things. In fact, there are quite a few different sockets made just for oil pressure switches/senders and every time I think I have all the ones I need a new style switch/sender is released. Figures. Anyway, you will have a lot of difficulty removing that switch using a plain 12 point socket of any size. I suggest that you buy one of the sockets or find someone who will loan you one. Any NAPA store will have on on the Lisle rack. The switch is simply a steel housing with a reinforced rubber diaphragm, electrical contacts, and a spring. On the day the leak started it was simply time for that rubber diaphragm to give up the ghost. No special circumstances needed. The usual failure mode is a slow but presistent leak. Yours was just a bit more dramatic. Maybe the black bakelite upper part is cracked allowing greater leakage. Pete in PA From: "Frederick Joslin" <fljoslin@xxxxxxxx> Date: Thu, 27 Jul 2006 20:05:33 -0500 Subject: Re: IML: Catastrophic oil loss It appears that the Safeguard Sentinel system sensor is leaking. The sensor is in very tight and I will have to work on getting it out. Weird that all of a sudden it would start to leak. It appears that no damage was done to the engine (I hope) so I feel very lucky. ----------------- http://www.imperialclub.com ----------------- This message was sent to you by the Imperial Mailing List. Please reply to mailing-list@xxxxxxxxxxxxxxxx and your response will be shared with everyone. Private messages (and attachments) for the Administrators should be sent to webmaster@xxxxxxxxxxxxxxxx To UN-SUBSCRIBE, go to http://imperialclub.com/unsubscribe.htm