Over the last week I've noticed that sometimes my glow plug light would not come on and sometimes it would. Now it completely stopped coming on. I know it's not the bulb because I have to crank it for a while and when it finally starts there is a cloud of diesel smoke....Ideas?

__________________
1985 Mercedes 300DT

Check the strip fuse. Do you have series or parallel plugs?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

i don't know...how can i tell?

__________________
1985 Mercedes 300DT

Do you have heavy squiggly bare wire joining the plugs together or a separate insulated wire to each one?
One bad series plug will cause all of them to not function.
If parallel and the fuse is ok you'll need to put an ohmeter on each one to test whether they are good.

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

Didn't all of the turbo engines come with parallel plugs? Did the no light and hard starting come on all at once or over time? I believe the gp light will still function normally with one bad plug but somewhere between two and all bad plugs will make it behave abnormally. Do start with the fuse though, then the ohms on the plugs.

__________________
Seth

1984 300D 225K
1985 300D Donor body
1985 300D Turbo 165K. Totaled. Donor Engine. It runs!!!
1980 300SD 311K My New Baby.
1979 BMW 633csi 62K+++? Dead odo

+1 to everyone's comments. This should help:

http://www.dieselgiant.com/glowplugrepair.htm

Good luck,

Scott

__________________
Scott
1982 Mercedes 240D, 4 speed, 275,000
1988 Porsche 944 Turbo S (70,000)
1987 Porsche 911 Coupe 109,000 (sold)
1998 Mercedes E300 TurboDiesel 147,000 (sold)
1985 Mercedes 300D 227,000 (totaled by inattentive driver with no insurance!)
1997 Mercedes E300 Diesel 236,000 (sold)
1995 Ducati 900SS (sold)
1987 VW Jetta GLI 157,000 (sold)
1986 Camaro 125,000 (sold - P.O.S.)
1977 Corvette L82 125,000 (sold)
1965 Pontiac GTO 15,000 restored (sold)

I think this is what he has, check at relay plug, red lead to each numbered plug, black wire to ground, I use the top of the power steering reservoir, the lower the reading, the better. I had a similar situation, one bad GP, replaced all, I'm funny that way, been good since.

__________________
83 SD

84 CD

On the parallel pencil type GP setup, if the GP in cylinder #1 is bad, or if two or more of the remaining four GPs are bad, you get no light.

Test/replace the strip fuse first. You can then test the GPs in place with an Ohm meter as suggested already. If you still can't figure it out, remove the GPs and bench test them on the battery, replace any that don't glow red hot within about 5 seconds.