Volvo D2-55: Glow plugs keep glowing

[Safc]

Hello all,

The glow plugs on my Volvo Penta D2-55 (2002) seem to keep glowing. The indication light on the panel switches on just when the engine starts. It keeps being illuminated, even after running the engine for 30 min. I keep measuring voltage between the glow plugs and the engine mount after 30 min, which means the plugs keep glowing imho...

Never experienced this before. Any ideas what the problem could be?

Engine/boat was idle in the water for 8 months in Italy. Started perfectly after this period, runs fine (no strange noises)...

Thanks.

[a64pilot]

Stuck relay? However when you get it fixed, check the glow plugs resistance, they are almost certainly burnt out. Hopefully they won’t be hard to remove as some swell when they get burned out.

[Bycrick]

Having the contacts on high-current relays stick together isn’t unheard of. I have a 70a box-style relay in my refrigerator control box. The controls tried to shut off the refrigerator about 0200. I didn’t catch that it was still running until I finally woke up about 0630. The fridge was down to about -20*. After having the same problem with the replacement relays (yes, plural) the problem turned out to be a badly SOLDERED joint on the high-current terminal that connected to the relay. The terminal would get hot, which caused the relay terminal to get hot and stick closed. The original manufacturer apparently didn’t have the right crimper for the heavy wire, so they’d soldered on the terminals. The bad joint was hidden under heat shrink tubing.