Outer Limits 4x4 Board

Okay, i am a bit dumb when it comes to diesels. I have never driven one until I got the GQ. The glow plug timer had s**t itself, so I had an auto eleccy put a push button in to heat the plugs until I get a new timer box. Of coartse I was warned to watch the time we hold teh button in otherwise we'll blow the plugs up.

Now, its having trouble starting in the morning. At LCMP yesterday had to use aerostart to get it going (it was about 5 degrees overnight). And this morning back at home it took a while to go also.

Q) Have we done a glow plug???
Q) Where the hell are they located?
Q) How easy are they to replace?

Forget the glow plugs - the temperature will freeze up the wax in your fuel and not help to get going!!!!

Just pay for teh timer to be be replaced - and stay places that are warm!

80diesel4play wrote:Forget the glow plugs - the temperature will freeze up the wax in your fuel and not help to get going!!!!

Just pay for the timer to be be replaced - and stay places that are warm!

man that's not really helpful. even with summer blend diesel you should not have any waxing until below zero degrees C. We have a month or more sub zero mornings here every year and both my diesels start first time every time. you should not even need to glow if the ambient temperature is over 20 - 25 degrees C.

if your truck won't start at 5 degrees chances are more like 3 - 5 glows are dead - having 3+ working is enough to start a 6 cylinder engine. probably a bit rough and smoky at first. I'm not familiar with Nissan glow systems but if they're anything like toyotas then the glow timer circuit will hit the plugs with 12V for a few seconds to get them hot quickly then drop the voltage to around 7v to keep them warm for start/run - if you've been using a pressbutton system which dumps 12v across the plugs it's possible you've burned them out.

the glow plugs are located on the top of the head, off to one side a bit, near the injectors. their centre electrodes are connected together by a strip of metal which is connected to a wire that will head off to the glow circuit relay. I agree that you should get the glow timer fixed or replaced, a GQ one shouldn't be that expensive from a wrecker and it should be a plug-in part so not hard to replace.

to test the plugs before removing them, undo the nuts that hold the strip to the centre electrodes, and remove the strip. test each plug individually for continuity (use a test light or multimeter) from the centre electrode to the negative terminal of the battery (ground). their resistance is very low so they should read continuous - if they read open circuit or more than a couple of ohms then they are bad.


the other thing you need to check is the condition of your injectors - if they are dirty or worn and the spray pattern is less of a spray and more of a dribble, it will make starting very difficult, running rough or smokey (black smoke), and fuel economy ordinary. if it's your first diesel you might not be all that worried by the fuel consumption since it's phenomenal compared to a petrol vehicle - a near stock GQ 4.2 litre diesel, no turbo, should deliver around 11 - 13 litres/100km if the engine is in good nick.

do you know the engine history esp with regard to injector servicing? how many km does it have - a 93 I'm guessing close to 200,000?

cheers

Brian

dumbdunce wrote:man that's not really helpful.

Agree....

dumbdunce wrote: if your truck won't start at 5 degrees chances are more like 3 - 5 glows are dead - having 3+ working is enough to start a 6 cylinder engine. probably a bit rough and smoky at first.

if you've been using a pressbutton system which dumps 12v across the plugs it's possible you've burned them out.

Okay thanks....

dumbdunce wrote: the glow plugs are located on the top of the head, off to one side a bit, near the injectors. their centre electrodes are connected together by a strip of metal which is connected to a wire that will head off to the glow circuit relay. I agree that you should get the glow timer fixed or replaced, a GQ one shouldn't be that expensive from a wrecker and it should be a plug-in part so not hard to replace.

about $250, genuine about $700!!!!

dumbdunce wrote: the other thing you need to check is the condition of your injectors - if they are dirty or worn and the spray pattern is less of a spray and more of a dribble, it will make starting very difficult, running rough or smokey (black smoke), and fuel economy ordinary. if it's your first diesel you might not be all that worried by the fuel consumption since it's phenomenal compared to a petrol vehicle - a near stock GQ 4.2 litre diesel, no turbo, should deliver around 11 - 13 litres/100km if the engine is in good nick.

do you know the engine history esp with regard to injector servicing? how many km does it have - a 93 I'm guessing close to 200,000?

cheers

Brian

170,000 now. I had injectors and pump overhauled when I bought it, about 8,000k's ago. and the economy is about spot on.

Excellent, thanks. Answered all my ?? really appreciate your time with that. Thats whats happened then, I have done glow plugs. Off to the wreckers we go for a timer, and get some new glow plugs.

HeathGQ wrote: about $250, genuine about $700!!!!

ow! Japanese parts are a rort :( find a diese GQ in a carpark and stel their timer

Heathcan'tstarthisGQ wrote:170,000 now. I had injectors and pump overhauled when I bought it, about 8,000k's ago. and the economy is about spot on.

that's all good then. a lot of first time diesel owners wouldn't bother, then would complain when it gives up without getting any love. there's not much cost benefit in a diesel when all's said and done but for simplicity and reliability it's no contest as long as maintenance is upheld.

HeathisgonnaspendalottamoneyonhisGQ wrote:Excellent, thanks. Answered all my ?? really appreciate your time with that. Thats whats happened then, I have done glow plugs. Off to the wreckers we go for a timer, and get some new glow plugs.

test the plugs first! you only need to replace the dud ones! and get aftermarket ones from Don Kyatt or repco or something, factory ones will be something like $80 EACH :(

dumbduncebeingfunny wrote:find a diese GQ in a carpark and stel their timer

I have nearly done this. I know of a GQ being wrecked, so I will organise that.

Cant wait till next week when my little bro gets back from NZ, he's a mechanic, so he can deal with this crap!!!!

dumbdunce wrote:

HeathGQ wrote: about $250, genuine about $700!!!!

ow! Japanese parts are a rort :( find a diese GQ in a carpark and stel their timer

Something else i just remembered - Nissan apartently had different manufacturers of the circuit board/box, so i need to find the right one to match the cicuyit in mine.

gayness! at those prices/dramas I'd be thinking about building my own from scratch - handful of heavy duty relays, a timer circuit to turn it off after a set time, only difficult bit is if it is anything like the toyota setup, you need a current sensing circuit to step the voltage down from 12v to 7v (approx - sticks a big resistor in series) to stop the 7V plugs from blowing up.

if you're more than slightly electronically skilled it wouldn't be too difficult a circuit to design/build, but would take a little research and a big ammeter to determine when the voltage cutover should be.. myeh, the more I think about it, the cheaper and easier it would be to go back to your pushbutton system, making sure the resistor is in the circuit, then you will never blow them up but on cold mornings it will take 20 - 30 sec of glow time to get it started.

What are glow plugs???? Never used them with my 2.8, I`d get in it after it had sat for a month or 2 without being started and just crank it over and it`d start straight away. It was the same wheather it was 30 deg and in the shed or -2 degs with ice on the bonnett.

guts, your toyota superglow system puts enough heat into the glow plugs even while cranking the starter motor that as long as there is good compression and the injectors are good the engine will start under most conditions. If you disconnected the glow plugs I guarantee it will be hard or impossible to start on a cold morning and if it does start it will run rough and nasty for 30 seconds or so until it gets some heat into it. it's yet another sad characteristic of indirect injected diesels.

My glow plugs are dissconnected from my lux

Guts wrote:My glow plugs are dissconnected from my lux

I find that difficult to believe but I spose I've got to take your word for it! if you were talking about starts at ambient temps over about 20C it's quite believable, but for an indirect injected diesel to start and run smoothly at subzero temps without any glow is pretty incredible.

is the engine in stock trim apart from having the glows disconnected? and why are the glows disconnected?? enquiring minds need to know!

cheers

Brian

dumbdunce wrote:

Guts wrote:My glow plugs are dissconnected from my lux

why are the glows disconnected?? enquiring minds need to know!

cheers

Brian

Because the motor is not in my lux anymore. Only messing with ya dude ,

I never tied it with the plug dissconnected, but it was like I said on the starting.

you yutz!


I was all set to get up early and go try starting the bundy with the glows disconnected.

Dam I should of let you go on it over night

1 thing I did notice was that if the batteries were getting old it would crank over 2 or 3 times before it would fire, if batteries were good then it`d go after the 1st crank.

hrm then I would have been obliged to hire some goons to come and kill you, and I'm broke, so it's all just as well really.


I might give it a whack later in the bundy just to see how it goes, never tried to start it without *any* glow, last time I replaced them when they were down to 1 good one and it would start pretty easy but be rough as GUTS until it warmed up a bit.

well i have a 1978 bj40 1b, with a push button installed in the dash, how long should i heat it for on a cold start.

P.S – i didn't put the button in.

Reddo wrote:well i have a bj40 with a push button installed in the dash, how long should i heat it for on a cold start.

P.S – i didn't put the button in.

7v plugs - about 2 - 3 seconds. 12v plugs, maybe as much as 6 - 8 seconds on a cold morning. should only need them for the first start in the morning.. although I hear Tasmania is almost arctic, maybe you'll need them all the time

experiment - on a cold morning try starting after say 3 seconds of glow - if it goes, try cutting it back to 2 seconds next time. if it doesn't, then you know to try 4 seconds next time. if they are 12v plugs, and they probably are in a BJ40 (3.0 litre B motor), then you won't kill them in a short time by leaving them on too long but too much glowing will eventually shorten their lives.

dumbdunce wrote:

Reddo wrote:well i have a bj40 with a push button installed in the dash, how long should i heat it for on a cold start.

P.S – i didn't put the button in.

7v plugs - about 2 - 3 seconds. 12v plugs, maybe as much as 6 - 8 seconds on a cold morning. should only need them for the first start in the morning.. although I hear Tasmania is almost arctic, maybe you'll need them all the time

experiment - on a cold morning try starting after say 3 seconds of glow - if it goes, try cutting it back to 2 seconds next time. if it doesn't, then you know to try 4 seconds next time. if they are 12v plugs, and they probably are in a BJ40 (3.0 litre B motor), then you won't kill them in a short time by leaving them on too long but too much glowing will eventually shorten
their lives.

Thanks very much for that, had me worried that i might of killed the little buggers.
they are the 12v kind and i never really heated the glow plugs longer than 7 seconds.

yor right about the weather, there was snow all over the place and if i get home in time might go for a spin.

Once again thanks very much for your help, It was much appreciated

Okay, well I found a good timer box from a wreck, and will be getting the auto eleccy to wire it in now. Get the glow plugs replaced, and the car will be back to normal again. Thanks for your input Dumbdunce.

good luck, hopefully that's all that it needs! hope you don't get screwed on the install!

Just as a extra point, one thing I have noticed in mine is that when I let the glow plugs warm up and the light goes out, if I wait a few moments longer you can hear the click in the engine bay as the others ready themselves, being in minus temps at times, it kicks over first time. Mind you I don't have to hold a button down. I can only imagine that this will happen on most diesels

Leprecaun wrote:Just as a extra point, one thing I have noticed in mine is that when I let the glow plugs warm up and the light goes out, if I wait a few moments longer you can hear the click in the engine bay as the others ready themselves, being in minus temps at times, it kicks over first time. Mind you I don't have to hold a button down. I can only imagine that this will happen on most diesels

Yeah I noticed that too. It must be the relay clicking to change the voltage down to the 7 volts (or lower voltage).

yeh my glowplug controller wasnt working (mq patrol), after reading the manual i found it was the temp sensor it wasnt working i just pulled the plug off it and they now heat for about 10sec, (should be 30 below 10deg).

I have ooe more question though mine always starts on less than 6 cylinders even with new plugs, and injectors could it be the fuel pump, or low compression???

btw as soon as you start it turns the plugs off and even if you turn it off it takes a couple of minutes in teh off postion for the timer to go when you turn it on

btw as soon as you start it turns the plugs off and even if you turn it off it takes a couple of minutes in the off postion for the timer to go when you turn it on

I'd hazzard a guess and say its your compression, cause I have a turbo diesel 4cyl and my compression is higher than normal I can't compare your problems to any that I have had So to an extent rules out the fuel pump as well as if thats playing up then your compression and power will be down as well.

Well, got into it last night. Glow plugs are 11v. Checked them all, resistance values were consistant 1.3 - 2.0 ohm. I replaced the 2.0 ohm with a new one (also 1.3 ohm).

With a multimeter checked the voltage going to em. Turn the key - 12v, relay clicks and down to 10.5v. To me, everything seems fine.


BUT THE F****** CAR STILL WONT START PROPERLY.

Once it starts, runs well. No smoke (apart from the big puff of white smoke), no sputtering, nothing.

(NED VOICE ON)Simspson, you are starting to annoy me.(NED VOICE OFF)

why not get tha auto leccy to swap your nissan over for a toyota

HeathGQ wrote:Well, got into it last night. Glow plugs are 11v. Checked them all, resistance values were consistant 1.3 - 2.0 ohm. I replaced the 2.0 ohm with a new one (also 1.3 ohm).

With a multimeter checked the voltage going to em. Turn the key - 12v, relay clicks and down to 10.5v. To me, everything seems fine.


BUT THE F****** CAR STILL WONT START PROPERLY.

Once it starts, runs well. No smoke (apart from the big puff of white smoke), no sputtering, nothing.

(NED VOICE ON)Simspson, you are starting to annoy me.(NED VOICE OFF)

As a idea what size battery are you running ? If this problem is really only happening in the morning could be you have a bad battery/terminals or connection somewhere.

when you arrive home and turn off the truck , give the lift pump a go to see how firm it is....then next morning give the lift pump another go to see how firm it is.....if its real soft and takes a while to pump up then you may have a leak in a fuel line somewhere .
my GQ had a leak in the lift pump around the shaft so i replaced the whole thing with a CAV unit.

funny thing is mine only sucked air in and never leaked diesel out....was a bugger to find what was wrong.

big red wrote:when you arrive home and turn off the truck , give the lift pump a go to see how firm it is....then next morning give the lift pump another go to see how firm it is.....if its real soft and takes a while to pump up then you may have a leak in a fuel line somewhere .
my GQ had a leak in the lift pump around the shaft so i replaced the whole thing with a CAV unit.

funny thing is mine only sucked air in and never leaked diesel out....was a bugger to find what was wrong.

I had the same problem with mine, was sucking in air, but for some reason one of the pipes connecting fuel line to the filter wasn't attached. Replaced tube and power went back up to 100%