Anybody know the actual size for a 1996 272? Boat is still in storage so can't measure it..... but might be looking for a replacement. Cleaned out the pitot (looked clean already) last year, blew out the line, but still not working correctly. If I blow compressed air into the back of the gauge though, it does move the needle. But doesn't work on the water. Might even look GPS, but I'm cheap!

Here's a pic:

it's kinda hard to tell from your photo, however.. the 272 that my buddy has has a 3 3/8" speedo and tach. His is a 2000 model, but the dash layout is similiar. If you can blow in the back of your gauge and the needle moves, I would assume that it will still work, you may need to replace the pickup or the tube...replaced mine a few years ago with a nice pickup and it lasted about a month before I hit something in the river and bent it. I said F&#$ it and took everything off the transom..going to put a GPS speedo in it, the analog one was never right anyway.....

My pickup is in the nose of the drive, and looks clean. Could be a bad tube also. I agree, GPS would be the way to go.