11v Glow plugs?

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Elv73

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So my 2005 CRD has been taking a few seconds longer to crank over on a morning now that the night time temperatures are getting a little lower here in Scotland. Nothing really bad but 3 or 4 seconds cranking before starting with a puff of grey smoke so I decided id change the glow plugs. Removed the alternator and took the first plug out to check what it had fitted before ordering new ones and found that it looks like the previous owner replaced them pretty recently (I bought it 3 weeks ago) but has used NGK 11v plugs instead of the 5v or 7v ones I was expecting to see.
Would I be correct in thinking this is the cause of the slower starting as the plugs wont get up to temperature when only being supplied with 7v?
I tested it with a 5v supply and it got hot but didn't glow, unfortunately I don't have a 7 v supply. 12 volts across it had it glowing red as I expected.
 

KJowner

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Put a meter on the glowplug rail to see what you are getting, I'll stick one on mine in the morning, I thought they were 12v but I'll check.
 

Billwill

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I have never used of 5 v or 7 v glow plugs for the CRD!

My 2002 Export CRD...2.5 L fixed Turbo, still has the original 11 Volt plugs...1 Volt gets dropped though the relays etc. from the supplied 12 Volts!
 
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KJowner

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Sorry, haven't checked mine, it rained all day.
 

Elv73

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Put a meter on the glowplug rail to see what you are getting, I'll stick one on mine in the morning, I thought they were 12v but I'll check.
The alternator and battery are out of the Jeep at the moment as im replacing both along with the glow plugs but I do know that the original glow plug control unit supplied 7v as I still have the sticker on the timing cover but some were changed to 5v during a recall when the oem ceramic plugs were replaced for steel plugs.
 
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Elv73

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I have never used of 5 v or 7 v glow plugs for the CRD!

My 2002 Export CRD...2.5 L fixed Turbo, still has the original 11 Volt plugs...1 Volt gets dropped though the relays etc. from the supplied 12 Volts!
Different glow plug control modules on the 2.5 compared to the 2.8. The 2.8 only supplies either 7v or 5v depending if it had the recall work done or not and was never sold with 11v plugs which I think is causing my slower starting in cold temps as the previous owner has fitted the wrong plugs (11v).
 

KJowner

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The alternator and battery are out of the Jeep at the moment as im replacing both along with the glow plugs but I do know that the original glow plug control unit supplied 7v as I still have the sticker on the timing cover but some were changed to 5v during a recall when the oem ceramic plugs were replaced for steel plugs.
Then your's is later than mine and Billwill's we have the early non vnt engines.
 

turblediesel

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US '05 2.8 CRDs had 7v ceramic glow plugs which tended to come apart. Metal glowplugs were 5v or 7v and dealers had a 5v glow plug controller modification they could do. Some skip the dealer experience and just run the 5v glowplugs with the oem 7v controller. I never heard about a recall.
 

Billwill

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South Africa is generaly pretty warm even in the middle of winter. I once disconnected all of my glow plugs on a cold day and started up the 2002 2.5L Export diesel...started up fine with some shaking and noise and smoke!;)

There are some mountains in Natal that have ski slopes operating in Winter sometimes and some highway passes do get blocked occasionaly.....I now live in the warmest part near to the Kruger National Park!:)
 

Yetiboy01

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So my 2005 CRD has been taking a few seconds longer to crank over on a morning now that the night time temperatures are getting a little lower here in Scotland. Nothing really bad but 3 or 4 seconds cranking before starting with a puff of grey smoke so I decided id change the glow plugs. Removed the alternator and took the first plug out to check what it had fitted before ordering new ones and found that it looks like the previous owner replaced them pretty recently (I bought it 3 weeks ago) but has used NGK 11v plugs instead of the 5v or 7v ones I was expecting to see.
Would I be correct in thinking this is the cause of the slower starting as the plugs wont get up to temperature when only being supplied with 7v?
I tested it with a 5v supply and it got hot but didn't glow, unfortunately I don't have a 7 v supply. 12 volts across it had it glowing red as I expected.
I fitted 5volt Bosch Part No: 0 250 402 003 / 0250402003 to my 7 volt system, jeep starts instantly, they have been infor 2 years now & still working well
 

Elv73

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I fitted 5volt Bosch Part No: 0 250 402 003 / 0250402003 to my 7 volt system, jeep starts instantly, they have been infor 2 years now & still working well
I swapped out the 11v plugs for those same Bosch 5v plugs yesterday and glad to say its fixed the slow starting and started straight away this morning with no smoke with the temperature at 0.5°c here in Scotland. It was a pig of a job but I'm glad it's done now before winter sets in.
 

Yetiboy01

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I swapped out the 11v plugs for those same Bosch 5v plugs yesterday and glad to say its fixed the slow starting and started straight away this morning with no smoke with the temperature at 0.5°c here in Scotland. It was a pig of a job but I'm glad it's done now before winter sets in.
They definitely aren't the easiest to change, I had 2 ceramic tips missing when I pulled mine out, not sure what happened to the tips but they weren't in the cylinder's? ( checked with a borescope, no damage could be seen ) very strange.
 

Elv73

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They definitely aren't the easiest to change, I had 2 ceramic tips missing when I pulled mine out, not sure what happened to the tips but they weren't in the cylinder's? ( checked with a borescope, no damage could be seen ) very strange.
Thankfully the plugs I was replacing were steel not ceramic, just the wrong voltage. They looked like they'd been changed pretty recently and thankfully came out pretty easily. The EGR elbow not so much lol
 
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