I have an O'Day 272 LE with a diesel engine. Since I have this boat (about 5 years) it has taken almost 2 1/2 minutes for the glow plug to get hot enough to start the engine. I was watching a video that shows the owner putting his finger on the glow plug and the starter button at the same time and the engine starts immediately. Is this normal? My engine has always started, but after watching the video I am wondering if there is something wrong with my glow plug that it takes so long.