do I have to wait before firing up??!

[glojo]

The point i was making was that a cdi engine will always start from cold without waiting for the glowplug light to extinguish, even if the glowplugs circuit was disabled the engine would still cold-start..

As for you saying that the glowplugs are nothing to do with emmisions...not true......here is part of the article in the link below.....

..."Because of this, some engines require that these glow plugs continue to operate even when engine is already running to regulate emission.

Among the automakers who also include these glow plugs in the vehicles they make is Mercedes Benz. Being a German automaker who lives in a country where cold season comes and go, they made their Mercedes Benz Glow Plug to be precisely engineered to work in this season and to reduce emissions and attain a significant fuel economy"....

http://www.guang-an.com/Directory/articles/1173.html

Nothing to do with emissions per sea

Just stop and please think what your saying.

On a really cold CDI engine if you do not wait for the glow plug light to go out the engine might not fire up straight away. If it does not start immediately, then fuel passes through the cylinder without igniting, thr engine then fires up and you get shed loads of smoke.

ANY diesel engine will start without the aid of a glow plug, it's just taht this great aid makes the starting so much easier. If you take the time to do a search on this forum you will find threads where owners have complained about there modern CDI engine taking up to 10 - 15 seconds to start first thing in the morning. There wasslight embarrassment when it was pointed out they should allow the glow plug warning light to go out, but the important point was this resolved the issue.

I respect your stance on this and it's all about choice.

Regards
John

 

[panason1c]

ANY diesel engine will start without the aid of a glow plug,

Absolute rubbish.


I would just love to watch you trying to start a cold Peugeot without the glowplugs working, including many other makes!

 

[glojo]

Absolute rubbish.


I would just love to watch you trying to start a cold Peugeot without the glowplugs working, including many other makes!

Your digging a hole.

In the 50's when we had real winter conditions my father owned a haulage company and I cannot recall any of his diesel powered trucks having an electric glow plug system. On a really freezing morning he would sometimes light a diesel soaked rag and chuck it under the engine to warm it.

I have worked off Iceland and had to start the old Enfield diiesel engines which had NO electronics whatsoever so please don't say you cannot start a diesel without glow plugs.

John

 

[panason1c]

Your digging a hole.

In the 50's when we had real winter conditions my father owned a haulage company and I cannot recall any of his diesel powered trucks having an electric glow plug system. On a really freezing morning he would sometimes light a diesel soaked rag and chuck it under the engine to warm it.

I have worked off Iceland and had to start the old Enfield diiesel engines which had NO electronics whatsoever so please don't say you cannot start a diesel without glow plugs.

John

You are the one digging a hole my friend, you appear to misread or misunderstand my posts, i simply stated that cdi engines will start from cold without the use of glowplugs, i agree that glowplugs will ASSIST a cold start but that they are also there to reduce emmissions....which you deny even though i've produced an article that supports my statement.

You then state that ANY diesel will start without using glowplugs!....well that, my friend, is completely untrue!.........there were some direct injection diesel engines produced (as were fitted in the Montego, etc) that would start without glow but also there were indirect injection diesels such as fitted in the earlier Peugeots, etc, that were IMPOSSIBLE to start without glow, even if a couple of plugs went down they wouldnt start!.

I might be wrong, but didnt truck engines fall into the direct injection category, hence why they would start without glowplugs?

 

[panason1c]

This article explains the difference between 'Direct Injection'
and 'Indirect Injection' diesel engines, it also confirms my thoughts that truck engines are direct.........


One of the biggest differences between diesel engines that can start without glowplugs and those that need glowplugs is the pre combustion chamber.This is a small chamber in the head of the engine, the diesel is injected into this chamber and ignition starts there.
Engines that can start without glowplugs do not have this extra chamber and are called direct injection engines. Some direct injection engines also have glowplugs to assist the starting.Smaller car engines are normally of the sort that do need glowplugs but big truck engines and some industrial engines used for waterpumps etc do not have glowplugs.
On some engines without normal glowplugs there is one glowplug in the intake manifold together with an injector. While the starter is operated this glowplug and injector is energised. This injector does not work like a normal one but is an electric device. This set up supplies the engine with some preheated diesel in the airsupply and helps the engine to start. You will find this on some tractors.

http://answers.yahoo.com/question/index?qid=20070901162756AAKqiPv

 

[glojo]

I might be wrong, but didnt truck engines fall into the direct injection category, hence why they would start without glowplugs?

Correct, your wrong regarding the engines I am talking about.

I think we are both looking to argue rather than find common ground. We both appear to agree that a CDI engine will definitely, undeniably start without waiting for the glow plug light to go out. It is simply better that when the engine is cold to wait..... That is all we are saying.

The specific engines you mention might be worn out, or they might be designed to start with the aid of a glow plug?? BUT a diesel engine works by compressing the fuel, the compression heats the fuel and this heat then causes the ignition. In countries that suffered from really cold temperatures they used to sell a different diesel mix which offered easier starting by igniting at a lower temperature. I have no idea if this is still the case but it would make sense,

A glow plug will also assist in this.

John

 

[Bazzle]

A glow plug assists the starting process BUT having experience with many diff types of diesels over the years we have always been able to start with faulty or inop glow plugs.
Generally the rule is that you need a battery with enough cranking power to continue to spin engine as it coughs and farts. Eventually when started even on 2 cylinders there is enough compression heat to fire all cylinders. Lots of white smoke and unburnt fuel but thats just the way it is.
This includes stationay generator sets, commercial diesels and light diesels in cars.

Of course you can cheat and squirt ether etc into intake...............

http://www.nulon.com.au/products.php?productName=Start_Ya_*******_Instant_Engine_Starter

Bazzle

 

[glojo]

Of course you can cheat and squirt ether etc into intake...............

They were the days

 

[BTB 500]

I hired a boat in the 70s and that came with a can of "Easy Start" for use every morning.

 

[sweeper]

For what it's worth, some kind of preheating is required on diesels engine to assist starting, direct injection engines start much easier and at lower temperatures without the use of preheating, modern diesel engines (and going back 10-15yrs) even direct injection car engines had glowplugs that stayed on during cranking and after start up to aid emmissions during warm up. generally speaking these new type of plug were a slightly different shape in that they were tapered at the end instead of bullnosed and were designed to be switched on for much longer.
The other type of preheat is known as flame start and basicly heats the air intake by igniting fuel in the inlet manifold. This was and is more common on large and direct injection engines.

 

[MBManInKen]

You then state that ANY diesel will start without using glowplugs!....well that, my friend, is completely untrue!

In a diesel engine, the combustion happens as a result of compression, which increases the temperature of the fuel. If compressed high enough, the temperature will exceed the self-inflammation point and the diesel will ignite. Therefore, in principle every diesel should be startable without using glow plugs.

However, the metal blocks of the engine are good conductors for heath energy and so it is possible that initially a lot of the heat generated by the compression gets absorbed by the engine block, which can keep the temperature of the fuel mixture under the self-inflammation point. That is why glow plugs are used on some engine designs.

In practice therefore, it could be hard to start a diesel engine without the use of glow plugs, although in most cases it should be eventually possible (well, if you have enough battery charge to keep trying ).

 

[MBManInKen]

Jadefox, you might not be meeting all of the requirements for starting when you experience this problem.

For example, on my s-class, the gear selector has to be in Park or Neutral and if the key was in position 2 (for example because you stopped somewhere and turned the engine off, but left the key in 2), it has to be turned back to 0 before starting again. All this is documented in the manual .

 

[BTB 500]

The small diesels I used for r/c aircraft were variable compression (via a contra-piston at the top of the bore), and it was normal practice to increase compression for starting ... more pressure = more heat, similar idea to plugs I suppose. As they warmed up you had to back the compression off.

 

[glojo]

The small diesels I used for r/c aircraft were variable compression (via a contra-piston at the top of the bore), and it was normal practice to increase compression for starting ... more pressure = more heat, similar idea to plugs I suppose. As they warmed up you had to back the compression off.

Don't forget all those cut fingers Happy days

Regards
John

 

[stats007]

All auto MB's with the DAS 3 key (electronic one) have tip-start.

That includes R129s from 1997 I think. I know MY99 cars definitely had it.

 

[BTB 500]

Don't forget all those cut fingers

Worst I had was from a 15cc glow 4-stroke ... that got me a trip to hospital

 

[glojo]

(and going back 10-15yrs) even direct injection car engines had glowplugs that stayed on during cranking and after start up to aid emmissions during warm up.

Ten years.... A small drop in the ocean of time
I note you come from Peterborough the land of the Perkins engine, 30 plus years ago I had to do a course where we had to strip down a P4 Perkins, do a top overhaul and put it back together?? I'm still trying to figure out why??

Before glow plugs, we used to start these engines in really cold climates by using a quick start, usually ether based. This lowered the temperature of ignition and made the starting easier, especially if we needed to hand crank it. Another method that was used was the de-compression lever. Use that to crank the engine and then move this lever and watch your hands. on bigger engines we would use a petrol donkey engine which would turn over the bigger diesel, plus of course there were the compressed air option which would again get the engine to spin until the diesel ignited, so yes the glow plug is a great aid and it is possible that some engines might not start without its use but it is plain wrong to even suggest that a compression only engine will always need an electrical glow-plug to start.

John

 

[robert.saunders]

Perkins, still at it here in P'boro - although we are famous for other things right now

 

[glojo]

Perkins, still at it here in P'boro - although we are famous for other things right now

I was going to start another thread regarding that issue Not nice.

Regards
John