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They weren't Wellman plugs were they, the market seems flooded with Wellman but they went bust some time ago. A google search shows they seem to have problems.
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As I was involved in the development of fast glowplugs by a (now defunct) British automotive company, I have an interest in this problem.
Tip breakage is one of the most difficult failure modes of a glowplug and generally results in engine damage unless you are lucky enough for the debris to be discharged straight away via an open exhaust valve. The turbocharger also is at risk from this type of failure. As glowplugs have become faster (in terms of heating time), the thermal mass of the tip has decreased and this type of failure has become more likely.
Factors incresing the likelihood of tip breakage are incorrect injector spray pattern and incorrect injection timing. The injectors should be checked if any parts are transferred to the new engine and the timing carefully set.
I too would be very interested to know the make of the failed glowplug. Have a very careful look at the others too. My recommendation has always been for Beru plugs - based on a lot of testing.
659.
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The make is Bosch. The outer casing of the tip broke off where it changes shape (like a crayon does towards its tip). What is interesting is the angle of the break - about 30 degrees to the horizontal when holding the plug vertically. The other three plugs have distinct marks on them in the same place and same angle.
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Bosch is a quality make, Have you asked Bosch automotive to look in to your glowplug issue?
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I am not an expert, but it does seem likely that you have faulty glow plugs as the other three are showing similar damage. The other possibilites are that you were supplied with the wrong glow plugs or the head design by Vauxhall is poor.
I think I would contact Bosch in the first instance and see what they have to say. I think I would be looking for answers as to why I was facing a £3000 bill and seeing if I could find somewhere to lay the blame.
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Roger
I read frequently, but only post when I have something useful to say.
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I don't think Bosch arevery good these days, and are one of the reasons many Gern and European makes which use their parts are unreliable. My Father had a similar thing happen to a Bosch Platinum plug in a BMW engine, the electrode and ceramic were gone, luckily they seemed to have been pulverised and blown out with the exhaust gas. Bosch said it was likely to be engine knock at high speed, yet both the plugs and the car had only done a few thousand miles and was cruising at about 45mph so seems unlikely.
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The presumption in law is that these glow-plugs were faulty at the time of installation, it is up to Bosch to prove otherwise, or that they were fitted incorrectly.
Get some professional legal advice and take out a claim in the Small Claims Court.
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the presumption in law is that they were fitted by a trained competant man and not by someone with a bicycle spanner set and a free sunday morning.................
i suggest spanners before you start taking professional advice and small claims action you talk to the customer service dept of the manufacturer they can tell you exactly why it broke,my theory is too much heat ,a colleague says wrong spray pattern of injector etc ..................
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I wouldn't consider any claims action against Bosch (or anyone else in a case like this). I've seen a few disputes over glowplug tip damage go to court, and you'll lose as soon as they turn up with their technical experts. They have had loads of practice fighting these claims and know all the tricks.
The angled mark on the plug tip you describe is normal. This is because the edge of the fuel spray cone from the injector is arranged to intercept the glowplug tip in order to initiate a rapid cold start. The degree of interception is very critical - hence the importance of a good spray pattern. Too little, and cold starting will be poor; too much and you'll cook the plugs.
My views for what they are worth: There is very unlikely to be an inherent problem with a Bosch glowplug correctly fitted and of the recommended type. It's vital that you check the applications list as plugs which look the same can be different. Injector spray pattern and timing have been mentioned, but I forgot an obvious one - are the plugs switching off after post-heat? Finally, and importantly, you must check the other three plugs - the impingement area should be well matched and there should not be any sign of a thermal fatigue line at the break point of the failed plug.
All told, not a lot of help to you, but it would be interesting to hear the results if you are able to make the checks I suggested. What make were the OE plugs?
659.
OE = original equipment.
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Just looking at your original post (always a good idea) I'm very surpised the OE plugs failed at under 45k miles. Depending on what make of OE plugs were in there, I would suggest that there could be an engine or system defect which caused this. Decent plugs well applied to a modern engine will generally last at least 75k miles. Even then, only an odd one will fail, rather like lamps in a chandelier. My PSA diesel hack still has one original Beru plug at 120k miles.
659.
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The original glow plugs were the GM gactory fitted ones.
I asked Vauxhall about faults in the glow plug circuit and the possibility of the plugs being always on - they said they could remain on however the warning light would also remain on instead of extinguishing after about five seconds which in my case the light went out as normal.
Injector spray pattern is a bit of grey area I have heard that diesel injectors can corrode (then effect spray pattern) because of the high water content in cheap supermarket fuel (don't know how much truth is in that statement). All injectors looked normal when I saw the engine in a thousand and one bits.
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All glowplugs stay on after the warning light extinguishes tho ' only for about five seconds until the engine picks up.If there is any water in diesel tanks at a supermarket,it will sink to the bottom of the tank,and be drained thro' a trap.Water is more likely to be found in local garages with less throughput and usually less maintenance-having said that all diesels are fitted with a very fine filter and a water trap which should be checked regularly.
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The glowplugs on your Zafira will surely only come on when the temperatre drops below 5c as with other Vauxhall diesels. So they wouldnt be operating at this time of the year.
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The extinguishing of the warning lamp is no indication as to whether the plugs are on or off. It is a common misconception that plugs switch off when the lamp goes out - in fact they remain on during cranking and post heat (the duration of which depends on jacket temperature). My PSA diesel will post heat for up to 5 minutes under very cold conditions; at this time of the year there is zero post heat. A faulty controller could leave the plugs on with no dashboard indication.
You can't check an injector spray pattern by looking at the nozzle - you need a test rig. The water issue is a red herring. Firstly, there is nothing wrong with supermarket fuel if it meets the appropriate standards (which they all do). Secondly, the filter will stop anything other than gross amounts of water getting through and finally, the pump would be damaged by water long before the nozzles.
659.
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Yet more problems getting my background info together before deciding whether I should point my broken glow plug at someone and ask them to pay:- I seem to have encountered problems confirming whether the plugs I was supplied with are 1) The right type and 2) Not fake. According to the Bosch website the part number etched on the plug does not exist. It is marked up as 0 250 202 042 and made in France. Any one know of any website links that may help find out if I was sold the correct item?
Got my car back, very nice quiet sounding, smooth running diesel engine costing a meer £2790 all in.
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www.segeka.lt/content/files/iskra.en.html
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TourVanMan TM < Ex RF >
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www.denso-europe.com/uploads/Glowplug/DENSO_GLOWPL...f
will give you bosh part numbers (exclude the spaces) to denso/car part numbers
------------------------------
TourVanMan TM < Ex RF >
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The Denso list shows two totally different plugs as the equivalent to a 0250202042-different sizes,diameters,fitting-when you see errors like this,you doubt the accuracy of the rest of their info.
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Go to a Bosch diesel service centre with your suspect plugs - all will be resolved.
659.
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Would seriously doubt a quality problem with bosch products but get to a bosch diesel service centre as mentioned above.
Bosch dont run away from genuine claims/problems.
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bosch bulbs arent up to the same quality they used to be mind.........as a buyer of these they seem to import them and stick their name on the box ,not very clever i dont think...got a flyer off osram yesterday their stuff still seems first class ........but never been offered it by the motor factors? suppose everything comes down to the old line in this country of "HOW MUCH"?????????
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Hi 659FBE,
As you know about Glow Plugs can I ask if the failure rate is any different between metal and Ceramic plugs?
I have just purchased a set of Denso Ceramic glow plugs for an old isuzu diesel engine in the VX cars(which have a post heat time of upto 6-8 mins), should I be worried about the these failing and causing engine damage as they are from Denso? Also is the use of copper ease on the threads worth doing?
Cheers
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Im a mechanic and Ive been in the truck / plant business all over the world for 30 years and never had a kick back from a ( genuine) Bosch glow plug, and I can tell you now that there are lots of cheapo copies of the bosch glow plug online and it is these that are failing NOT the genuine item.... in fact, bosch are so concerned about it that they are now supplying their plugs in a special anti pirate box so you can see if they are the original item. Bosh, Beru and NGK are the best brands, dont even think about others. Beru are fitted by most European manufacturers in their new cars, some fit Bosch and japs usually fir NGK....BEWARE of cheapo copies online, only purchase from shops and other trusted sources. Yes..I recommend that you fit your plug with coppaslip or similar, another tip is to remove them when the engine is at operating temp, this helps stop the steel plug threads tearing at the alloy head if you have one. A healthy engine will fire up on a freezing morning with 2 out of 4 plugs inop, but will run initially for a minute with a LOT of diesel knock before smoothing out. If you dont have a torque wrench, just nip them up, if one isnt tight enough you will hear it chuffing away so nip it a bit more, better bit by bit than too much. Post 2002 cars have a long after start heating period, this is to help bring the cat up to operating temp quickly to reduce emissions during warm up but also places more stress on the plugs. you can expect a bosch plug to last 50,000 miles on a short run high stress basis so the average plug will need changing every 5 years normally, and as the best way to test them is by removing them, I recommend replacement.... at 50,000 or 5 years whichever comes soonest
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Whilst I would agree with most of the above, I would definitely advise against removing glowplugs with a view to refitting. Ceramic glowplugs should absolutely never be refitted - always fit a new one.
In fact, refitting a glowplug is unnecessary as the best way to test a glowplug is in-situ with an ammeter. Apply the rated voltage to the isolated plug (note that some plugs are rated considerably below 12V; 7V is a common figure for ceramic plugs) and measure the current with a suitable ammeter. An old vehicle type ammeter is ideal.
A good plug will draw a highish current (10 - 20A) for a second or two, which will then drop to a steady state current of about 7A. Test all of the plugs in this manner and change any failed plugs.
Ceramic glowplugs need to be handled with the utmost care prior to fitting - one knock to the tip may cause breakage in service. A torque wrench is advisable in order to reduce the chances of damage to the plug body. I also advocate the use of a copper based anti-seize agent to the plug threads - but not to the taper.
659.
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Better still, just test them with an ohm meter - they should be typically 0.3- 0.6 ohms when cold. When they fail they are either open circuit or very high resistance > 1K. You can even use a 12v lamp in series with the battery to check - a failed plug wont light the lamp.
Many years ago I had an incidident with Bosch spark plugs bought from a cheapo motorist discount. where the tip broke off and bent the exhaust valve on the way out of a Saab engine. Examining the boxes they came in I concluded they were chinese fakes. In those days the motor factors even sold "Dirling" Brake Padss!!!
Remember a lot of Bosch products are nowadays made in China, even my very expensive Fridge freezer has a compressor made in malaysia. Bosch is not the quality product it once was - it charges premium prices because of the name.
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You can't test glowplugs properly with an ordinary ohmeter - the only reliable indication it will give is an open circuit plug.
By way of an illustration, a cold glowplug (element and ballast) will draw say 20A at 11V giving a resistance of just over half an Ohm (550 mOhms) which will rise to about 1.6 Ohms as the current falls to about 7A.
A standard set of test leads have a resistance of about 0.5 Ohms, neglecting any termination resistances so unless a 4 wire measuring technique is used with a high resolution meter, the indications given with standard instrumentation will be useless.
Glowplugs are cleverly designed with a ballast section within the body of the plug and a heating coil at the tip. The ballast is wound from material with a high positive temperature coefficient of resisitance such that a large current will flow initially in the circuit which gives a rapid warm up of the heating coil. Such a high current if maintained, would burn out the heating coil so the ballast is arranged to increase in resistance after about 2 secs of operation to reduce this current whilst maintaining the tip temperature.
More information on the Beru website.
The ammeter test will show the integrity or otherwise of both the ballast and the element by allowing the change of current to be observed as the plug operates. This cannot be done with any type of ohmeter.
659.
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