No "glow" Glow Plugs

greg_g · Oct 11, 2004

Re: No \"glow\" Glow Plugs

( What you've described is just plain -Parallel- electrical conection... I know it is a tad nit picky.. but for the electrical novices that have just taken basic ac and dc electronics.. the use of series and parallel in the above fashion may confuse some)
You're not considering the whole circuit Chris. When ganged by bussbar (jumper wire on two cylinder models), the glow plugs represent a parallel segment in a series-parallel circuit. It's dead simple to draw out yourself. At the risk of being redundant, it goes
SUPPLY
battery (+12v)
cable
starter solenoid
wire #2
system fuse
wire #3
ammeter
wire #5
ignition switch
wire #12
All in series so far, agreed? None of the paralleled glow plugs will operate if there is an open anywhere in the supply segment of the circuit. Series. So let's take it from wire 12 again, still in series:
wire #12 (series)
bussbar or jumper wire #13 (parallel)
glow plugs (parallel)
cylinder head (parallel)
GROUND
negative cable (series)
battery (-12V)

A 30A system fuse will blow long before a bussbar/jumper could possibly melt, so any open in the paralleled segment will not interrupt the circuit to the other glow plug(s). But an open in either series segment, kills the entire circuit. Series-parallel.

I keep saying, that one of these days you're actually gonna have to BUY a Chinese tractor. Once you've invested some troubleshooting and maintenance hours on these things, the dinosaur technology will start making more sense to you.

//greg//

Inspector507 · Oct 11, 2004

Re: No \"glow\" Glow Plugs

 when any glow plug burns out, the current is reduced and the voltage increases 

In a 12 volt system the voltage can never go up higher than 12 volts. And the glow plugs ARE rated at 12 or above.

Inspector507 · Oct 11, 2004

Re: No \"glow\" Glow Plugs

OK, you have a combination series-parallel circuit. What CHRIS (Soundguy) said was the glow plugs are connected in parallel, but just that part of the ciruit.

RICHARDG · Oct 11, 2004

Re: No \"glow\" Glow Plugs

OHMS,VOLTS,AMPS,,I got a simple test for you,,its starting to get cold,right? Well,,,,I have a 254,,,but I bet this part works about the same,,,,the first morning or evening it gets down to about 35 degress,,try starting it without glow plugs,,,see how that works out,,if yours is like mine it will take a few trys with out glow plug useage,,,now the next cold morning,,pause your switch on the glow plug postion,give it 1/8 to 1/4 throttle,,give it 15 seconds or so,,,than try it,,if yours is like mine,it will start in first try,you will know if glow plugs work or not,,,and yes nortrac is very good about standing behind what they sell,,mines a nortrac too. thingy

Soundguy · Oct 11, 2004

Re: No \"glow\" Glow Plugs

( You're not considering the whole circuit Chris. When ganged by bussbar (jumper wire on two cylinder models), the glow plugs represent a parallel segment in a series-parallel circuit. It's dead simple to draw out yourself. At the risk of being redundant, it goes )

We may be running into some terminoligy and nomenclature problems.

When i went to school, the series / parallel issue concerned the load on the circuit, and current flow.. The fact that a wire runs from a battery to a fuse to a switch and then to two parralleled lamps, and then to ground does not specifically make it a seriesl parallel circuit, because there are a couple non load components in the circuit. The load components being parallel are the main 'makeup' of the circuit.

Change that and have battery, fuse, switch, resistor, and then two paralleled lamps and then you have a circuit that has series and parallel load components.. or as you said.. a parallel segment in a series circuit.

Again.. this may be pure nomenclature. You don't here people refering to accumulators when talking about 'registers' in modern computers. condensor is generally used only when refering to 'old' equipment.. whereas capacitor seems to have more widespread usage. Same with rentogens vs rads when looking at radioactive measurement. I'm not sure how it was taught when you were picking up your electronics background. I pretty much was taught to view a circuit as current flow. A circuit that has a battery in common, and lots of loads that each reference positive and negative, is a parallel circuit.

In the circuit you mapped out in your messgae.. there are lots of wires, switches, etc.. but each load device is essentially directly referencing positive and negative. There are no series loads in that circuit. The relay is referencing +/- .. the glow plugs are also each individually referencing +/-.

If there were load or other ballast type resistors in line with the positive feed wire then it would be another story.. Or if they were using load devices in series.. say two 6v lamps in series to handle the 12v power source... etc.

To view it another way.. current in a series circuit is constant . No matter where you break a simple series circuit and insert your meter, the current reading will be the same.

Current flow in a grouping of paralleled circuits may not be the same, it will depend on the load in question. To ilustrate this.. take 4 resistors of differing values.. wire them in series, and connect to a power source. No matter where you break the chain and insert your meter.. the current flow will be the same. Take those same 4 different value resistors and place each of them across the power supply.. because each has a different resistance value.. the current flowing thru each resitor will be different.

Mix those two circuits, and you will have a constant current reading when taken in line with any of the series components, or with the paralleled segemt, measured as a hole.. move into that segment, and different parts of the segment will be conducting different amounts of current, that when taken as a whole, will equal the current that is flowing thru the other series components elsewhere in that circuit.

( A 30A system fuse will blow long before a bussbar/jumper could possibly melt )

On paper sure... in the real world, all it takes is corrosion on that buss bar.. or physical damage to make it fail Generally though, not counting a failure.. you are correct. If the system fuse blows.. the rest of the circuit should be unpowered. However.. after reading back messages here.. the chineese engineers wiring these things don't seem too accurate, or consistant. I've just went back and found at least 4 instances/reports on non-standard wireing involving fuses, lack of fuses, extra wires on dash gauges.. etc. On new tractors.

( I keep saying, that one of these days you're actually gonna have to BUY a Chinese tractor )

Again.. no need to buy a chineese tractor to talk about an electrical circuit design.

( Once you've invested some troubleshooting and maintenance hours on these things, the dinosaur technology will start making more sense to you )

That technology is 'george jetson' light years ahead of some of my tractors. Consider the 30's era science that went into the fords i collect and work on. Leather seals in the engine, non pressurized cooling systems, Simple user controlled charge rate by adjusting the third brush on a dc generator, etc. Mechanical lifts on some of the earlier machinery, hand clutches, etc.

Soundguy

schmalts · Oct 11, 2004

Re: No \"glow\" Glow Plugs

Actually, its because the Flux capaciter is not putting out 6.6 gigawatts of power.

greg_g · Oct 12, 2004

Re: No \"glow\" Glow Plugs

( Actually, its because the Flux capaciter is not putting out 6.6 gigawatts of power. )
Ain't that the truth.....ToolManRick is probably in hip boots by now.

//greg//

ToolManRick · Oct 12, 2004

Re: No \"glow\" Glow Plugs

Slush, slop, gurgle gurgle. Deep breathing...

Hey, got that little amber diode indicator light installed on the glow plug circuit. Put it on the dash in between my parking brake light and the charge/run light. Easy to see. Cute little light beams a nice amber glow whenever the ignition switch is passing over the "H" position. AND, should the ign. switch screw up and juice the glow plugs in the run position I'll know it for sure. Now if those replacement glow plugs were only here.

ToolManRick · Oct 14, 2004

Re: No \"glow\" Glow Plugs

Update.
Haven't installed the new glow plugs yet. I did get three new ones UPS yesterday evening. I did put an OHM meter on them and ARRggg, 2 read 1.7 ohms and 1 read --- (open). Drat. Called Kirk at NorTrac again and he was openly disappointed about 1 being faulty and put another one on the truck. They have been very good about it. They still didn't want the 4 bad ones sent back for verification. Good sports they are. Hope they checked the one they sent yesterday. I'm going to look like I'm trying to rip them off if it too is faulty. Got my fingers crossed.

Soundguy · Oct 14, 2004

Re: No \"glow\" Glow Plugs

You would think they would have checked ALL of them before they sent them.

QC in action...

Soundguy

JohnS · Oct 14, 2004

Re: No \"glow\" Glow Plugs

SoundGuy,

I think you are being a bit harsh on the dealer. Does JD and NH dealers do QC on parts before sending to the customer? They probably assume they are good from the manufacturer. Unless Northern has seen a high incedence of open glow plugs, which we don't know, I wouldn't expect them to test every part that leaves their shelves. Sounds to me, they sent the parts out ASAP, and was very responsive to the customer. Not something that they should be dinged for, IMHO.

Soundguy · Oct 14, 2004

Re: No \"glow\" Glow Plugs

I'm not sure it was too harsh. As 'nice' as it was to try to get the parts to the person fast.. I don't see 'high' marks for sending out defective parts. I tend to think the responsibility falls more with the actual manufacturer.. but as we all know in business, the dealer is the 'face' the customer sees.

When I get an incorrect meal at a restaurant.. we all know it is pretty much a kitchen/chef fault.. not the waitress.. yet she is the one that has to go get it fixed.. etc.

Besides... If you pay your money ( warranty is a paid ahead item) you should expect correct working parts.. I realize we are all human and accidents / errors happen.. but in those cases.. the dealer / manufacturer needs to take the responsibility/financial burden ( and blame ).

As for qc checks on parts from the dealer? Hmm. I can't answer with any certanity.. however.. I can say I've never got a wrong/defective part from the JD NH and MF dealers I deal with locally.. Not sure what that says.

When i worked in a water meter manufacturing facility we spot checked units for calibrated flow , say 1 out of 100. However each individual unit got a blow test before being packaged. The blow test was done with air and confirmed the rotor in the meter spun and made the meter move.

We shipped out about 10k meters a day with 4 production lines. So.. qc to some degree IS possible even in hi production environments. In the 4 years I worked at that plant ( ABB ) I very seldom recall getting DOA meters back. Of the few I ever did see that were returned immediatly.. most were damaged in transit.. or had a cosmetic defect. However we did get the occasional early failure back. ( Our units carried a 2 year complete repair/replace warranty.. and a 20yr limited warranty... we built good products and stood behind them.. )

Soundguy

JohnS · Oct 14, 2004

Re: No \"glow\" Glow Plugs

Well, I doubt that Northern sent out a known defective part. QC belongs back at the manufacturer, which at best is a sampling method. Are you willing to pay the price for 100% inspection and test of every part, that goes into the tractor and testing of the tractor? You are talking military pricing and higher. So, given your requirements, if Northern sent out an alternator, that should check all the windings and do a load test prior to shipping? I don't think that is realistic. Given this kind of expectations, I suggest you not to purchase a Jinma, from anyone.

RICHARDG · Oct 14, 2004

Re: No \"glow\" Glow Plugs

Northern shipped me a steering arm,thingamagigy,just because I heard somewhere,that a couple had broke,free,never used it,,sent me a new hydro screen,overnight,cause when I took mine out,it had two dimed sized holes in it,free,,,they also sent me a new trans dipstick,free,,just cause I heard that some were hitting gears,,[mine wasn't],,and I wanted one for plugging and one for checking.They also paid for a new battery,,,complete reinbursal of a very good name brand. When you go to auto parts store and buy any part,,its not checked to see if it works right or not at the store,,,the manufactor is supposed to do that,,,northern don't make these tractors,or their parts,they just stock them,,,,but I bet you all one thing,,cause of this,,they will take note,,and probably do something in the positive about it,,,but one thing nobody knows but northern,,how many they sell/replace,,,I've never heard of anybody having to replace their glow plugs on any of these boards in the two years or so that I've been bothering people on them,,,the manufactor of any item is responsable for q.c.,,,the customer dictates what standards he wants,,he is q.a.,,northern may dictate that all glow plugs be tested before shipment,,,this of course could make glow plugs cost twice as much,,,so if nothern only issues/sells 12 glow plugs a year,and all but one worked,,well....... thingy

Harrygoodwrench · Oct 14, 2004

Re: No \"glow\" Glow Plugs

Speaking from personal experience right up to today I find defective parts on equipment every day and this is stuff made right here in the good old USA.
What really annoys me is the "lack of workmanship" and this I accuse all manufacturers of, including many in my own USA companies I see.
With that said its hard to throw stones at anyone dealing with overseas parts etc. Which I might add are mostly oversees components but assembled here.
QC it seems interfers with production and that takes precidence. I'm all for quality control but its hard to expect a parts guy to guy what a Ohm check is supposed to be noetheless how to check it.
When was the last time you spoke to a "real" parts guy? There are some still around but not many.

Soundguy · Oct 15, 2004

Re: No \"glow\" Glow Plugs

( Well, I doubt that Northern sent out a known defective part )

I take that as a given. I'm sure if they picked up a bag with the part in it and it was cruched into powder.. they wouldn't ship it.

( QC belongs back at the manufacturer, which at best is a sampling method )

I'd agree to that, mostly.

( Are you willing to pay the price for 100% inspection and test of every part, that goes into the tractor and testing of the tractor? You are talking military pricing and higher. So, given your requirements, if Northern sent out an alternator, that should check all the windings and do a load test prior to shipping? )

Not every part.. but at least some parts.. especially ones easy to test.

Every genny/alternator/starter I've ever bought has ahd a test tag on it or I say the rebuildre put it on the bench before handing it over.

Same with injectors. I don't recall ever having had injectors rebuilt and handed back over wiothout a pop test done on them first.

The list goes on. A part like a glow plug should be abale to be assembly line tested for go/no go with a simple continuite check. May electronic devices are checked in this manner.

I guess what we are getting down to is not to expect above average parts and qc service from an economy company. ( this isn't specifically a negative view. As you more or less point out.. the money savings comes from somewhere, and as was also pointed out.. the warranty is still covering the continued stream of defective parts that is leaving the factory.. even if it is taking a few more days to do it.. )

Rought casting don't bother me... minor parts changes, fluid changes and battery changes, and oring problems don't bother me either. I just have a hangup about being shipped a defective part. Part of this comes from my comercial background. When one of my 500,000$ pieces of cat equipment is brok down on a job.. and I order a part from cat.. I darn well expect it to arrive in working order, as I'm probably loosing 4digit income per day while the machine is down... Heck.. I expect the parts from my NH dealer for my hobby tractors to be correct too.. but then.. so far I guess I've been lucky.

Taking a step back to hobby tractoring and non comercial work, I see where this line of thinking doesn't fit in with an economy tractor that has in some cases.. hand fit parts that may not be assembly line 'identical' to other units.

Looking at the original post.. I'd give the dealer / manufacturer 'A' for effort.. but 'F' for performance. Lets face it.. getting 3 bad gp's on a machine is bad luck.. getting a 4th bad one in the shipment of 3 replacements isn't bad luck.. and it goes beyond inefective QC work.. it goes back to bad manufacturing process or tooling, or lack of workforce training. From a statistical point of view.. that's a terrible failure rate, especially when figuring parts dispersion...there is always the possibility of 'bad lot' however given the time difference between the practor assembly and the replacement shipments.. one would think that lot would be used.. unless we are talking a very close time frame.. etc.

To paraphrase.. I'm not criticizing the tractor in general.. just elements of its manufacture.. be that materials or tooling, or labor.

There is a point, when you are figuring 'total cost of ownership' that something ends being a deal when nuisance problems outweigh economy... For instance.. I don't think I'd rely on my old 8n for comercial work... too often you have to dink with it for a few minutes before working. However for hobby use.. that is half the fun.

Soundguy

Soundguy · Oct 15, 2004

Re: No \"glow\" Glow Plugs

( I find defective parts on equipment every day and this is stuff made right here in the good old USA.
)

I agree.. the overseas people don't have the patent on manufacturing defects.

( What really annoys me is the "lack of workmanship" )

The problem in question could very well have been a labor issue, as opposed to tooling or materials. And again.. theat's everywhere.

( When was the last time you spoke to a "real" parts guy? )

Ditto.. Unless I know that they are a good parts person.. I usually refer to them as counterperson.. as they only look in a book and read from the 'script'.. much like a telemarketer, they usually have no knowledge of the parts they handle. This is deffinately true of places like radio shack. I can remember 20 year ago going into a radio shack store.. and the people they hired wre more tech oriented than sales oriented. Nowadays, you walk in and they ask you if you want a cell phone. You say no and ask where the potentiometers are and they give you a blank look.. then you restate it as where are the rheostats? again blank look.. finally you drop to variable resistor.. and that resistor part usually gets them going enough to shove you in front of the tray of all their resostors, and them hoping you know what you are looking for... funny enough.. this reminds me of a 'jiffy store' story. Kinda along the same lines as radio shack. I walked in and asked for a pesticide.. got a blank look.. rephrased as insecticide... ( not being smart.. just in a hurry.. ).. 2nd blank look and I finally blurted out 'bug spray' which got a smaile and a point to the correct isle.

I do live in the south.. and I had already though of that answer.. and in a way.. it is an answer.. though just not for the south. Seems like the general education level of our country is on the decline. Things I take for granted as every day common public knowledge that I learned in high school are becoming increasingly less apt to be seen. A cynical friend likes to point out that the IQ of the planet is at a constant.. yet the population is growing ( people in general are getting dumber.. i.e. knowledge is getting diluted ). Makes ya chuckle to think about it. The smarter we get as a race.. the more we leave behind. Take computers for instance. I grew up 'banging' on bare metal. I missed the real dinosaur stuff like card wallopers.. but go in early enough to still learn and use them.. alsong with many of the early processors and systems in the mid 70's. A good computer tech back then was just as much into the hardware as the software. Problems with one could usually be traced to the other by simple observation and diagnostic procedure.

Nowadays.. the CLI is out and GUI is in.. people don't know how to format a disk unles it involves right clicking... I went in to an office supply store and had a question on a computer part.. they sent over their computer person... he knew virtually no hardware.. especially if it was out 3 months ago.. and he knew alot about a few of the common application softwares in use. past that he was a wet noodle... I did better by putting my glasses on and reading a few boxes and tring to glean usefull info out of the mix of buzzwords and marketing catchphrases that adorn 95% of the outter covering of most boxes I picked up. Same when calling for tech suport. As soon as I figure out that they are reading from a script.. I know the boat is sinking even faster. The rare exception when you get a real tech or product engineer on the line you feel very garetefull. The network administrator at the school my wife works at might as well wear bg shoes a red ball nose that lights up and a multi colored with with matching face paint. I'm guessing he's running their windoes server by cookbook. He constantly fixes the computers which usually then requires manual intervention by a teachers husband or son to come in and undo the damage the sysadmin has wreaked. He will answer questions about disk usage and allocation with frighteningly vauge answers. For instance.. my wife was unable to save some emails and he informed her that she had used up her alotted space. Knowing that she only had a few saved files, she asked where the space was being used. he remarked that he dint't know.. but 'something' was using alot of space.... I emailed him and asked him where all the space she was allocated was being used.. he couldn't even pull up a directory to view file sizes without my assistance. Turns out it was some sort of a file system allocation error.. ( probably due to his lack of maintenance of the system! ) How he landed that cushy job I'll never know...probably nepitism.

Oh well.. this one drifted quite a bit. Guess I better give the soap box a rest...

what were we talking about? tractors? Lets get back to that.. much more fun.. no matter what color they are.. or where they come from! /forums/images/graemlins/wink.gif

Soundguy

GRUMPA · Oct 15, 2004

Re: No \"glow\" Glow Plugs

Working in manufacturing in the states, here's how the parts thing works here. I work for a big manufacturing place but we make surgical and airplane parts mostly. When the parts are on the machine its up to the operator to check parts. Generaly a percentage of parts not all (takes to much time). When it goes to the inspection dept depending in the tolerance they will check only lets say 10 out of every thousand done depending on the tolerance. If a part has lets say .010 tolerance it will be 1 out of every 100 parts made. In this country they use standards like I.S.O (International Organization of Standards) and S.P.C. (Statistical Process Control). They use neither in other countries but are adapting them but at a snails pace.

Most small parts for any larger unit are sub-contracted out and not done at the main plant. When a plant orders lets say XXXXX units of whatever they expect the parts to be made according to the blueprint and wont check them until they get alot of rejections. Being in another country alltogether the main company will never know there product is bad because it never reaches there ears. Putting it this way you buy a car and you get a bad spark plug, the dealer just changes it out and your on your way, you actually think the manufacturer of the car will be notified, I think not. Especially if it dosent effect the whole line.

The parts we make if we assemble them are tested 100%, But foreign manufacturers dont do that, thats one reason they can sell things cheaper, it cuts down on costs.

ToolManRick · Oct 19, 2004

Re: No \"glow\" Glow Plugs

Just thought I'd bring this thread to a proper close. Got the remaining glow plug yesterday (it was a good one) and installed it. Now I'm all set for winter if it gets cold enough to need the plugs. Thanks guys for all the input.