i am less than amused right now... one of my brand new loop plugs has failed tonight and im not sure why... when i changed the plugs last time i made sure the holes were all reamed properly... any ideas other than switching to the pencil plugs?

Is it always the same cylinder?

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Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

no this time it was #1... last time was #4

Maybe glow plug relay contacts sticking on occasionally?

__________________
Palangi

2004 C240 Wagon 203.261 Baby Benz
2008 ML320 CDI Highway Cruiser
2006 Toyota Prius, Saving the Planet @ 48 mpg
2000 F-150, Destroying the Planet @ 20 mpg



TRUMP .......... WHITEHOUSE
HILLARY .........JAILHOUSE
BERNIE .......... NUTHOUSE
0BAMA .......... OUTHOUSE

Are they staying on when they should be off?

__________________
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

A good example why there is NO good reason NOT to change to pencil type. Last longer, work much much better.....

__________________
Jimmy L.
'05 Acura TL 6MT
2001 ML430 My Spare

Gone:
'95 E300 188K "Batmobile" Texas Unfriendly Black
'85 300TD 235K "The Wagon" Texas Friendly White
'80 240D 154K "China" Scar engine installed
'81 300TD 240K "Smash"
'80 240D 230K "The Squash"
'81 240D 293K"Scar" Rear ended harder than Elton John

thats coming...


in the meantime i cant for the life of me figure out why it will not glow now... there is power to all four plugs and yet it still will not glow

So there is power at plug 1 and power at plug 4, insulators are in the correct location but the plugs are not getting hot?

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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

correct

What is the voltage at each plug?

__________________
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

it was 12v at the first one then went down on each... i don't remember exactly but i can check again tomorrow

The below pic is from the Mercedes Service Manual.

Attached Thumbnails

 

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84 300D, 82 Volvo 244Gl Diesel

I am thinking the above would indicate an open Circuit in the #1 Plug due to the Loop/Filament being burned; or, there is an open circuit in the Ground Wire/Strap or in the Temp Unit that the Ground Strap goes to (if your year has one).

When you are probing with the Volt Meter you are providing a complete good circuit because grounding the circuit with one of the Voltmeter probes.

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84 300D, 82 Volvo 244Gl Diesel

Good point. What would be the appropriate way to check for voltage without running into this conundrum? Would checking the voltage at each plug from input wire to output wire avoid this issue? I think it would because the process would be depending on the ground thru the downstream end of the system and not putting the probe directly to ground itself??

__________________
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 used this tutorial today to check my GP system:
http://www.dieselgiant.com/glowplugrepair.htm

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'84 190D 2.2 OM601.911 144K