Definately grabbing at straws here, Peter N, what do you think ?
I only have a little air coming from the filter/pumo housing, and only really when revving high.
This morning, the clear tube from here to the injection pump was 99% full of fuel (just a small bubble at the top by the filter/pump housing), meaning that the injection pump had absolutely plenty of fuel.
Still took probably a minutet to crank uo and file, slowly getting faster until it fired. In this process, there is always quite of black smoke coming from the exhaust, also indicating that there is plenty of fuel (albeit probably unburnt). Eventually it starts and does so each time throughout the day.
Maybe I will try changing he oil and filter. The car originally came from Italy last Christmas and probably has summer weight oil.
Maybe it is indeed a cranking speed issue but not being a diesel specialist, I don't know just how critical this is ? It doesn't crank all that slowly in the morning, as I have abrand new battery, but it definately fires as the enqine gets up to full crank speed.
Opinions/debate most welcome..............ebt
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Hi,
If you are getting black smoke when you finally get going you are getting fuel to the cylinders and that is unburnt diesel. It sounds as if you need something to heat the cylinders or the air going into them. As you mention temperatures of -20 this is most likely the cause. I remember years ago a particularly harsh winter, where the firm I worked for had a truck that would refuse to start when cold. The only way we got it to start was with a hair dryer shovved up the air intake. The hot air would make it fire up almost immediately. I can't offer a solution to your problem, but maybe its worth a try with a hair dryer once. If it works you know you're on the right track to fixing it. You may have to fit some kind of pre heat system in the air intake.
Hope this helps
Robin the Technician
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Interesting Robin, thanks. Not sure "she indoors" has one, but worth a try.
When I lived in upstate NY, they use to use oil pan (sump) heaters overnight in the winter to aid starting.
I'm gonna bite the bullet and go for an oil change first as it may indeed have Summer weight oil as the car originally came from Italy.
ebt
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Greetings Comrade,
Replacement Fuel filter (inc primer) Finis 1096950. Price in UK £78.28.
Re connectors - scrapyard is your best bet in my opinion.
If i were you I'd try sealing off the plunger "seal" with thick grease. lower viscosity oil , in fact everything the Eleckie & A/C Doc says.
hth
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Cranking speed IS critical with a diesel as the air in the cylinders has to heat by compression.
If it`s on `Summer grade` oil - perhaps a mineral 15w40 given it`s age. It has absolutely no chance at -20c.
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Thinking I'm gonna have to invest in Mobil 1 0W-40 and a new filter, but again, EXPENSIVE I think..... :-)
SQ
Edited by Dynamic Dave on 21/01/2010 at 12:42
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Ouch !!! last option that will be at £78.28.
Are you saying the air goes in around the plunger edges ? Grease sounds like a good diagnostic option. I may bypass it temprorarily as the best diagnosis, but I simply can't work outside at -20c, as it is today. As stated earlier, more air seems to ingress as revs increase, (logical).
SQ
Edited by Dynamic Dave on 21/01/2010 at 12:42
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Those 1.8 engines do tend to start like that, you have to wind them up, my son has one in a P100 pick up, as you say if there is smoke from the exhaust when cranking air ingress is probably not the problem. Cranking speed is of the essence in those sort of temperatures so as others have suggested, a very thin oil would seem to be the remedy. What I did many years ago on my Perkins powered vehicles was to fit an extra battery in parellel with the existing one, or you could connect another battery in series with it to start, giving 24 volts, but make sure its only connected to the starter.
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I couldn't afford Mobile 1 0W-40 but am changing oil and filter tomorrow morning.
I'm going for Esso 5W-40, fully synthetic, which my local garage and combined parts supplier sells and installs all the time for the local cars, all of which operate in the same climate as mine.
I have a brand new battery, so the car starts each morning, but I am concerned at the cranking time and would like to resolve it for peace of mind.
Will update with new news when available.....ebt
(thanks for your opinion, much appreciated)
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I would think that would improve it considerably.
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OK, Esso 5W-40 fully synthetic oil and filter replaced this morning.
It was -23c in my car this morning and even some of the locals diesels didn't start.
The brand new Fiamm battery continued to crank this morning until it started :-)
Update tomorrow............ ebt
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In summary, I think it was all about managing my expectations.
The max/min thermometer today I put in was car last night read -25c.
The car started after about 30 seconds of cranking, in fact it's like this each morning when it's so cold.
I guess I expected it to start in the same manner as when it's +20c here, which of course is stupid. This is the first year I have lived in such a cold climate and I didn't reset my 'expectations'.
If anyone has any experience of running diesels in such low temps, I'd appreciate their feedback on cranking times.
Of course, if I had a garage, it would be different/ But imagine it - the engine/head block is an almost solid mass of steel, sitting at around -20c out in the cold wind. IT HAS to be more difficult to fire diesel fuel as such low temps compared to +20c.
It will take time to build up the correct temp to ignite the fuel air mixture, even with a fuel heater and glow plugs.
Any feedback on this logic would be appreciated.
I used to tell people that on older cars, new plugs/leads/distributor cap was a good investment in winter to negate the obvious failure possibilities.
Now, I firmly believe that a tip top condition battery is key for diesels in freezing conditions......ebt
Edited by Dynamic Dave on 23/01/2010 at 13:57
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When I first started running diesels back in the '60s you would never be able to start one in this country at that temperature, apart from the lack of cranking speed the fuel used to solidify. Lorry drivers used to light a fire under the engine. The technology is far better now though but because a diesel is a compression ignition engine its always going to struggle in very low temperatures.
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I suppose it also possible that there may be marginally less compression due to metal shrinkage...
(coefficient of linear expansion and all that :-)
Thanks Pete.........ebt
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Was in Poland before Xmas, and everyone that give me a lift, seem to preheat there diesel engine 2-3 times, even when the car was warm.
Maybe worth giving the glow plugs an extra heat or two tomorrow.
Good Luck.
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I actually have been doing it for 4 or 5 times. I also learnt (by reading the Preheating section in my Hayes Manual) that the glow plugs are kept connected and hence hot) for between 10 and 30 seconds after the car has started, depending on the ambient temperature.
And all these years I thought they were taken out of circuit when the glow indicator goes off on the dash ! :-)
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Well, it was -28.8c in my car overnight and guess what-----NOBODY'S car started, even one petrol based Golf. I think that some of them had stood for maybe a day, but battery o/p at that temp was simply not enough to crank my engine long/fast enough to fire up.
SO, I popped down to my cellar (or underground as the Latvians call it) and got my last battery to help. I keep it constantly charged to the full (with an intelligent microprocessor controlled charger) and the ambient temp is between +10c - +12c down there.
Guess what, the car fired up VERY quickly and I was then able to help out others.
Think I'll just keep that spare battery for just these sort of freezing morning !!!
Cheers everyone....................ebt
Edited by Dynamic Dave on 24/01/2010 at 11:36
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All's well that ends well !! Was only -13c last night and it fired up almost immediately.
Couple of questions for Peter N or someone else if time permits.
1/ In a non common rail diesel, where is fuel pump and what type of pump is it that moves fuel from the tank to the priming pump, filter, and eventually the injection pump.
2/ In a common rail diesel, am I right in assuming that there there is a high pressure pump supplying fuel to common pipe/rail and this then feeds individually ECU controlled injectors ? Where does it get mixed with air ?
Cheers......ebt
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Common rail engines have a pump in the fuel tank to deliver to the high pressure pump mounted on and driven by the engine, your assumption is correct, the pump delivers fuel at a constant pressure to the fuel rail and into the injectors which are ECU controlled.
The mixing of fuel and air takes place inside the cylinders, as with all diesels. On the inlet stroke each cylinder takes a full charge of air which is compressed bringing its temperature high enough to ignite the fuel, a measured ammount of fuel is then injected determined by the throttle position.
This arrangement is one of the things that makes the diesel more efficient, it can run on a very lean mixture, if you run a diesel at full throttle it looses a lot of its economy, they reward gentle driving and strangly, a larger enginen can give better economy, not if you use all the extra power of course, but for a given power output it will be using a leaner mixture.
Peter
Edited by Peter.N. on 29/01/2010 at 17:51
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So the measured amount of fuel (governed by ECU/throttle position indicator) is injected into the combustion chamber AFTER the air has been compressed and ready to ignite the fuel ?
Wow, there must be tremendously high pressure in the common rail then ? However, I assume the outlet of the injectors much be extremely small, or the pressure needed would be astronmic ?
I assume the injectors have a valve/some sort of shut off to prohibit blow back upon combustion ?
Lastly (and thanks) where and what type of fuel (delivery) pump is used on
non-common rail diesels ?
Have a good weekend.............ebt
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>>So the measured amount of fuel (governed by ECU/throttle position indicator) is injected into the combustion chamber AFTER the air has been compressed and ready to ignite the fuel ?
Even pre-common rail they were 'intelligent' enough to inject the fuel in more than one pulse per cycle. I remember being very impressed on reading this for the Perkins Prima in my old Maestro. Apparently it was done to reduce the diesel 'rattle' (apologies to our Mancunian friend).
>>Wow, there must be tremendously high pressure in the common rail then ?
Yes. Don't even think about 'cracking an injector' on one of these.
>>I assume the injectors have a valve/some sort of shut off to prohibit blow back upon combustion ?
Only the piezo crystal (?) valve they use to regulate flow. Fuel can't combust in an environment that doesn't contain air/oxygen.
>>Lastly (and thanks) where and what type of fuel (delivery) pump is used on
non-common rail diesels ?
All my pre common rail diesels used a mechanical pump.
Anyone else can feel free to point out any errors I've made here.
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>>I assume the injectors have a valve/some sort of shut off to prohibit blow back upon combustion ? Only the piezo crystal (?) valve they use to regulate flow. Fuel can't combust in an environment that doesn't contain air/oxygen.
I wasn't concerned with cumbustion here, rather that the combusted charge in the chamber could blow back through the injector. How come that doesn't happen ?
>>Lastly (and thanks) where and what type of fuel (delivery) pump is used on non-common rail diesels ? All my pre common rail diesels used a mechanical pump.
But is this pump at the fuel input side of the injector pump or elsehwhere in the fuel line ?
Cheers................ebt
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Early engines used a lift pump similar to the early petrols, the fuel was then dilevered to the high pressure injection pump. Early ones of those looked very much like a small engine, with four or six 'cylinders' in a row, which were of course high pressure pumps. In the '50s they brought out the 'rotary' or 'distributer' type pump, these contained one pump but a distributer system wherby the fuel was directed to each cylinder in turn.
Modern IDI engines still used this type of pump and even some of the DI engines, athough with a much higher pressure. they are much more reliable than common rail systems.
I think that the best IDI engine produced was the Peugeot 2.1td, I have three of these in Citroen XMs and a life of 300,000 + miles is not unusual, and 50 mpg plus driven with a little restraint.
I did my first diesel conversion in 1959 when I fitted a Perkins 4/99 engine into a Vauxhall Cresta, that engine was one of the first to use rotary pump. Perkins did a series of conversion kits to fit a large proportion of the cars made at the time.
About 25 bhp per litre was about the norm then, seems to be about 100 now! The Perkins 'Prima' engine that the previous post mentioned was one of the first direct injection diesels and a considerable advance in technology, the early ones were very noisy but as mentioned the mechanical two stage injection quietened them considerably by making a small pilot injection before the main one so that the fuel was already burning when the main injection took place, resulting in a much smoother and quieter burn.
Injection systems have always been very tough, the early ones use a pressure of around 2,500 psi, in those days there were dire warnings of fuel spray penetrating the skin, now the pressure is about ten times that and can be lethal.
Edited by Peter.N. on 29/01/2010 at 22:47
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Thanks for you insight and memories Peter...ebt
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