Post Reply 
 
Thread Rating:
  • 0 Votes - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Glow plugs
Donny Dog
 

Posts: 773
Joined: Feb 2012
Location: United Kingdom
Post: #1
Glow plugs

I have an SD4 due in March. Having never had a diesel car before, I wasn't aware until reading the on-line manual that diesel engines still use glow plugs. The reason I say this is that I have a boat with Volvo D6 diesels which don't have glow plugs. From what I can gather, the high compression alone is enough to raise the mixture to ignition temperature. The design is very effective, as, even from winter cold, the engines start the moment you turn the key (so quickly you don't even discern any cranking).

May I ask of those who have Evoque diesels how quickly they start from really cold temperatures? Also, as they don't have auxiliary heaters, how quickly does the engine warm sufficiently to heat the car? As an aside, does anyone know why auto diesels use glow plugs when there are optional designs? Is it just a lower compression issue? Thanks!
07-02-2012 06:31pm
Find all posts by this user Quote this message in a reply
cjfp
 

Posts: 2,917
Joined: Nov 2010
Location: Hampshire
Post: #2
RE: Glow plugs

The other day at -6 I pushed the button and it took about 5 secs for the glowplug light to go out before starting.

Car is warming in minutes.

Pure 3dr SD4 Tech Man ; Firenze Red ; 19" Style 3 ; Pano ; Ebony / Ivory Int ; Auto dim rear view ; 2 seats ; Park Aid - Rear cam ; Ext. folding mirrors ; Adap Xenon ; Fogs ; Mud Flaps ; Side Steps - Rec'd 28/12/11 - Sadly going 6/6/14 - Gone, now running BMW X6
07-02-2012 06:35pm
Find all posts by this user Quote this message in a reply
Donny Dog
 

Posts: 773
Joined: Feb 2012
Location: United Kingdom
Post: #3
RE: Glow plugs

(07-02-2012 06:35pm)cjfp Wrote:  The other day at -6 I pushed the button and it took about 5 secs for the glowplug light to go out before starting.

Thanks. That seems quite a long wait to me! (Pleased to hear the car warms up quickly, though).
07-02-2012 06:41pm
Find all posts by this user Quote this message in a reply
cjfp
 

Posts: 2,917
Joined: Nov 2010
Location: Hampshire
Post: #4
RE: Glow plugs

It's the only time I've had to wait more than 1 sec.

Pure 3dr SD4 Tech Man ; Firenze Red ; 19" Style 3 ; Pano ; Ebony / Ivory Int ; Auto dim rear view ; 2 seats ; Park Aid - Rear cam ; Ext. folding mirrors ; Adap Xenon ; Fogs ; Mud Flaps ; Side Steps - Rec'd 28/12/11 - Sadly going 6/6/14 - Gone, now running BMW X6
07-02-2012 07:16pm
Find all posts by this user Quote this message in a reply
XFullFatTim
Bat wielding forum enforcer

Posts: 9,295
Joined: Oct 2010
Location: Somewhere between here and there.
Post: #5
RE: Glow plugs

They are pretty quick, it takes my Defender 10-15 secs at normal temperatures for the glow plug light to go out

A Pangea Green New Defender 110 First Edition is now sitting on my drive alongside British Racing Green Electric Mini Cooper SE Level 3. After 21 years in my hands my TDI300 90 was handed on to the next custodian on 15 July 2022.
07-02-2012 07:25pm
Find all posts by this user Quote this message in a reply
Donny Dog
 

Posts: 773
Joined: Feb 2012
Location: United Kingdom
Post: #6
RE: Glow plugs

(07-02-2012 07:25pm)XFullFatTim Wrote:  They are pretty quick, it takes my Defender 10-15 secs at normal temperatures for the glow plug light to go out

It sounds as if they are as good as they can be. I have no basis for comparison car-wise, but I still wonder why glow plugs are needed (as discussed in my first post).
07-02-2012 08:09pm
Find all posts by this user Quote this message in a reply
XFullFatTim
Bat wielding forum enforcer

Posts: 9,295
Joined: Oct 2010
Location: Somewhere between here and there.
Post: #7
RE: Glow plugs

Any diesel engine specialists here to explain? Here is the Wikipedia explanation http://en.wikipedia.org/wiki/Glowplug

A Pangea Green New Defender 110 First Edition is now sitting on my drive alongside British Racing Green Electric Mini Cooper SE Level 3. After 21 years in my hands my TDI300 90 was handed on to the next custodian on 15 July 2022.
(This post was last modified: 07-02-2012 08:41pm by XFullFatTim.)
07-02-2012 08:40pm
Find all posts by this user Quote this message in a reply
MartinP
 

Posts: 479
Joined: Nov 2011
Location: SOUTH WALES
Post: #8
RE: Glow plugs

Uh......I think I prefer blissful ignorance rather than trying to understand how it works and I guess I can wait a few seconds to start the car.

Retired! SD4 Manual, Prestige 5 door, Havana with Ambiance interior, plus lux pack and spare wheel.
Arrived! SD4 Auto, Autobiography 5 door, Kaikoura Stone with Tan interior, HUD/Solar glass, ACC, Lane Departure warning, Sign recognition plus spare wheel. Built 16 March. Collected 2 April.
[Image: 129200.png]
07-02-2012 08:52pm
Find all posts by this user Quote this message in a reply
RacingSnake
 

Posts: 1,267
Joined: Sep 2011
Location: Reading
Post: #9
RE: Glow plugs

(07-02-2012 08:09pm)Donny Dog Wrote:  It sounds as if they are as good as they can be. I have no basis for comparison car-wise, but I still wonder why glow plugs are needed (as discussed in my first post).
i have no direct industry experience, but I would hazard a guess that igniting purely by compression would require extremely high compression ratios, which combined with the reliability and mass-productivity required in cars would make it too expensive?

I do however, believe there are some cars out there without glow plugs, I believe the dodge ram is one, but it heats the diesel in the inlet before it is injected... So it has a similar effect as a glow plug, just via different means.

I dont know how long marine engines run for before an overhaul... 5000hours? 10,000hours? Not sure I could see them running for 200,000hours without work, which is what I think you should expect from a production car.

Ordered: Fuji Dynamic Lux Coupe / style 7 wheels / Privacy glass / adaptive xenons / something else which I've forgotton.
Should be end of April (was March, then April, then end of May/June).
Collected, Friday 13th Shocked April 2012
07-02-2012 09:58pm
Visit this user's website Find all posts by this user Quote this message in a reply
XFullFatTim
Bat wielding forum enforcer

Posts: 9,295
Joined: Oct 2010
Location: Somewhere between here and there.
Post: #10
RE: Glow plugs

The marine engines I deal with - really BIG ones not matchbox sized boat engines - don't have glow plugs at all, the fuel is preheated to very high temperatures before it gets to the fuel injector, also to start the engine we use compressed air to "blow" the engine over and momentum does the rest.
Big marine diesels run until they breakdown these days, its the ancillaries that get all the maintenance rather than the actual engine. The engines I sail with are very very big like 13.5m high weighing in at some 3000 tonnes. Take a look at the Wartsilla Sulzer RTA96c http://en.wikipedia.org/wiki/Wärtsilä-Sulzer_RTA96-C

A Pangea Green New Defender 110 First Edition is now sitting on my drive alongside British Racing Green Electric Mini Cooper SE Level 3. After 21 years in my hands my TDI300 90 was handed on to the next custodian on 15 July 2022.
(This post was last modified: 07-02-2012 10:48pm by XFullFatTim.)
07-02-2012 10:40pm
Find all posts by this user Quote this message in a reply
Post Reply 


Forum Jump:


User(s) browsing this thread: 2 Guest(s)
babyRR is an independent web site and not affiliated with Land Rover