300 Tdi won't start...just out of the blue!

Angus, You need two things to run an internal combustion engine, 1/ Oxygen 2/ fuel, and of course those elements must be in the correct proportions, Your thoughts that the LPG injection system is the culprit, would, I think be spot on. If for some reason LPG is injecting before the engine is started that would indeed give such a rich mixture in the cylinders deplete of that essential oxygen that the engine would not fire up easily on the starter or when it did eventually get enough oxygen into it, the massive fuel load will cause a severe detonation, (the start up noise you are hearing), which by the way has the potential to severely damage your engine.
Some of the first heavy transport trucks to be fitted with these LPG systems reportedly broke cranks, rods and destroyed pistons until systems were refined.
As previously advised, turn off the gas system at the bottle and see how that works out, there may be an issue with the injection system.

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Originally Posted by big guy

Put that battery on charge if possible, Its still under warranty actually, receipt should be in the folder I gave.I believe its nationwide.

I never put new plugs in but had the ones in there tested and the spray pattern was fine. Took it to diesel tuner after the LPG was fitted and in conjunction with the EGT gauge had it checked and tuned bu a diesel tuner. Receipt should also be in the folder.

You may wanna check the alternator for charge rate but its a newish Alternator so that should check out o.k also.

To get you out of trouble, just swap batteries over, the 2nd one is not a cranking battery but will be fine for a little while.

Cheers

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Hey Big Guy, I think you might mean you had the injectors checked as glow plugs are just a small element that heats up the combustion chamber a little bit and doesnt spray anything.

The glow plugs are very easy to check.

Just disconnect the wire off the top of it (8mm 1/4 drive socket) being careful not to drop the nut, use a deep socket (can't recall what size) to pull one out at a time to keep them in order (just my pedantic ways) and by clamping the body/thread with the negative jumper lead clamp and holding the positive to the top where the nut was you will see it glow with in about 5 seconds.

If they take more than about 8 seconds they are getting old and wont work as your timer only lasts 8 seconds and if they dont glow at all, touch them on a piece of paper to see if they are getting hot at all ***not a good idea to actually touch them***.

The light will go on even with the glow plugs disconnected as they are on separate circuits from the timer, I know this as mine were disconnected for 4 years as previously mentioned.

300Tdi's will start in normal Australian conditions relatively easily without glowing and the GP's are there mainly for those few times where it will be colder than it will allow the diesel to ignite from the heat created by the compression only so don't stress about the glow plugs.

I would still if it is not starting easily when cold look at the filters and the lift pump as they both affect cold starting considerably and I know from experience that they will crank slow when low on fuel or when the lift pump does not pick up fast enough.

Glad to hear all is well though, put a good 600+ CCA battery in the bugger and they start well, I run twin Delcor Calcium batteries in mine, have done for 5 years and they are still going strong.

Pricey but well worth it, just make sure your alternator is charging at over 14volts and Calcium batteries will live for a long long time, if your staying with standard lead acid then you want it under 14volts or else they can have a shortened life.

Cheers Casper.

OOps. My mistake, had the injectors checked for pattern and plugs for glow.

I do agree to some degree with you and also not.

The 300 tdi is a old donk and as the air gets compressed and heats, the fuel(diesel or alternative oil as diesel were originally intended to run on) gets injected. The plugs prewarm the chamber to aid a more complete combustion.

I would still recommend especially now in winter here in Oz, I know its not 10C below but still cold it will not harm but reduce diesel getting washed down bores and reducing wear.

About 9 months ago I had the pleaseure of heaving both the head chef and one of the mechanical engineers from Mercedes in Bremen(North Germany).

Although some was lost in translation, I pretty much understood what he was trying to say.

He also funny enough adds a litre of petrol to the tank every now and than.
Not the newer diesels but likes of the Landy donk. Cleans fuel lines and injectors and is much cheaper than a dedicated injector cleaner.

Makes it go a bit better too.

Detleff(his name) has a 300d which has done over 500k km's he recons and frequent oil and filter changes are the key plus letting them warm up gradually by driving normally and also putting under load on a regular basis will prolong their live to stop glazing or something on the bores.

Anyhow Ben, I am pretty confident that a good charge will do wonders on the battery and as said at least 600cca starting battery.
The guys(auto electrician said that what is in there is what is recommended but by whom they never said.
They did a few things on the car at the time and I trusted them untill 3 months later when I did an oil change and found the little battery.
I actually went back and their anwer was that it starts and that is fine.

Well, it wasn't fine as I wanted a big ass cell there and they just did what they thought was right.
Although it never gave me trouble, I thought it never cranked as well as it could have.

Let me know how you get on.

Hi to your Mrs too.

Casper and Big guy are both correct.

Direct injection diesels (which the 300Tdi is), need glow plugs a lot less than IDI diesels.

200/300Tdis and 4BD1s will start quite happily anywhere in Australia in winter without glow plugs.

There are plenty of truck/tractor/industrial DI diesels around with compression ratios 18:1 or higher and no glow plugs.

The tdi and 4BD1 diesels are around 16:1.

It can't hurt to use glow plugs, but they shouldn't really be needed. I noticed that with the retarded ignition on my 300Tdi the glow plugs made a big difference.

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Originally Posted by isuzurover

The tdi and 4BD1 diesels are around 16:1.

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The compression ratio of the 300Tdi is 19.5:1 . :) Reference is the owner's manual.

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Originally Posted by nice1guv

The compression ratio of the 300Tdi is 19.5:1 . :) Reference is the owner's manual.

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Ah - cheers. I thought it was about the same as the 4BD1.

There are plenty of 19+ :1 diesels out there which were never fitted with glow plugs.

Quote:

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Originally Posted by big guy

OOps. My mistake, had the injectors checked for pattern and plugs for glow.

I do agree to some degree with you and also not.

The 300 tdi is a old donk and as the air gets compressed and heats, the fuel(diesel or alternative oil as diesel were originally intended to run on) gets injected. The plugs prewarm the chamber to aid a more complete combustion.

I would still recommend especially now in winter here in Oz, I know its not 10C below but still cold it will not harm but reduce diesel getting washed down bores and reducing wear.

About 9 months ago I had the pleaseure of heaving both the head chef and one of the mechanical engineers from Mercedes in Bremen(North Germany).

Although some was lost in translation, I pretty much understood what he was trying to say.

He also funny enough adds a litre of petrol to the tank every now and than.
Not the newer diesels but likes of the Landy donk. Cleans fuel lines and injectors and is much cheaper than a dedicated injector cleaner.

Makes it go a bit better too.

Detleff(his name) has a 300d which has done over 500k km's he recons and frequent oil and filter changes are the key plus letting them warm up gradually by driving normally and also putting under load on a regular basis will prolong their live to stop glazing or something on the bores.

Anyhow Ben, I am pretty confident that a good charge will do wonders on the battery and as said at least 600cca starting battery.
The guys(auto electrician said that what is in there is what is recommended but by whom they never said.
They did a few things on the car at the time and I trusted them untill 3 months later when I did an oil change and found the little battery.
I actually went back and their anwer was that it starts and that is fine.

Well, it wasn't fine as I wanted a big ass cell there and they just did what they thought was right.
Although it never gave me trouble, I thought it never cranked as well as it could have.

Let me know how you get on.

Hi to your Mrs too.

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I definitely just wait for the glow plugs to warm up each time and it starts first crank no problems...so long as the battery is up to it of course ;)

That's really interesting about the petrol...so would you genuinely say it's a good idea to put in a litre of petrol and run it through the car every now and then and this would be a "good" thing and wouldn't wreck anything? People are always so careful not to put normal petrol in a diesel...that'd be pretty interesting if that does good things for it though.

Cheers Frank, my wife says she's still after some of those crumple cups she saw at your place...I think you can get crumple glasses too, very cool design those things...not cheap though dammit hahaha I guess if I can have a Landy though she can have some crumple cups eh ;)

Thanks everyone for the info too, this really is a great forum.

Hey Big Guy, I'm not against glow plugs just that they are not the be all and end all when it comes to starting a 300tdi.

My Disco has now done 383,000kms and for about 200,000 of that I have not had the glow plugs working and it's still going strong.

Thanks Isuzu Rover for explaining it a bit better, I have seen several Deutz, Kubota and Yanmar engines big and small with de-compressors over glow plugs along with several small stationary engines such as Robin (Subaru) which do as well.

Mercedes had a de-compressor in one of their diesel cars as well, I can't recall the model but one of my old bosses had one and when I used to move it to wash it I used to get a laugh out of the huge puff of smoke when it started.

I always waited until the gardener was walking past to start it :D

Cheers Casper

I hear you all and seen much of the glow plug debate.
Not until a trained engineer has explained it to me, have I taken the time to always start on plugs, I even wait for the Navara glow plugs to pre-heat.
My wife on the other hand in the Golf is always in a hurry and just gets in and goes.
At least I try.

With the petrol thing, I admit I often put a litre in the tank with the petrol and was fine.
As far as doing damage, I will not put my name to it but surely can't do any worse than injector cleaner?!

Give it ago and see. Those old 300 tdi's I build tough, very tough and the pumps from my info I got from the net can take it too.

Now, the crumple cups are wicked and only last week, did a friend brake another one and now will have to get another.
I will look into the glasses too, might get some for the Bar.

Cheers mate and fingers crossed it all works out.

Perhaps a battery charger would not go astray in your shed either, always very handy.

Cheers

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Originally Posted by big guy

Now, the crumple cups are wicked and only last week, did a friend brake another one and now will have to get another.
I will look into the glasses too, might get some for the Bar.



Cheers

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off topic,
but what are these crumple cups you are talking about?