Glow Plug Problem Nissan

[Tough Ombre]

Hi everyone, I just got a 27 Sport Cruiser in the water after an extensive winter of work. I changed the glow plugs only to have some melt after 4 hours. The inside of one shot out and we limped into Noank CT on 5 cylinders with lots of smoke and noise. Fortunately, all on board were hearty souls . I think it could be the glow plug circuit not shutting down after start up. Any thoughts? The motor is a Nissan LD28.
Thanks!

[Mark Deeser]

I had to replace ignition switch on mine, same engine, when I did i put glow plugs on push button right next to switch. When I let off button I know they are off, and if I should choose I can heat while cranking. Worked for me.
Thanks, Mark.

[Tough Ombre]

Thank you Mark for your input. Did your glow plugs melt too. One of the tips is completely gone which makes me wonder if it is in the motor, eviscerated or blown out. Since first posting, I tested the circuit and the glow rail has 11.5 volts when key is in glow position and .25 volts when off. I like the idea of a push button glow switch. BTW the new glow plugs are made by Autolite. Thanks!

[Mark Deeser]

My plugs did not melt, they were 30 years old and didn't do much of anything. I would not in your case be concerned with engine damage, take steps to correct and enjoy a great boat. Thanks, Mark.

[Tough Ombre]

Good News! I had changed the injector timing belt over the winter and found out that if the timing is advanced the glow plugs can deform and even break. I spent the day at the marina, taking off the main engine pulley and marking everything. I finally took off the timing belt and moved the injector pulley counter-clockwise one cog; thus retarding the timing. I put the belt back on, along with everything else and started her up. It was immediately evident that the motor was much quieter and the soot and smoke (which I thought was "normal" for a diesel) were gone! I let her run for an hour and checked a glow plug; looked perfect so I took her for a cruise. The noise has dropped at least 50% and she is faster, cruising efortlessly at 7.5 knots. As my late dad would say "Everyone deserves a day like this sometimes."

Thanks to all.

[Mark Deeser]

Great news, would be nice if we all could have a few more days like that. Happy cruising.