Page 1 of 2

Jx glow plug query

Posted: 20 Jul 2014, 15:43
by what2do
Ordinarily, van starts on the button with some heat, BUT, just been out to start it and notice the yellow glow plug light didn't illuminate and it took 20 - 30 seconds to start. Balls.

Course of action required please. What's the first thing to be checking with the multimeter? Hoping to diagnose this tonight and make any purchases first thing in the morning.

Thanks in advance, mitch.

Re: Jx glow plug query

Posted: 20 Jul 2014, 15:58
by kit
Check the fuse first.

Re: Jx glow plug query

Posted: 20 Jul 2014, 19:08
by keith
Fuse doesnt look like a normal automotive fuse.....its a metal strip. Found in the black box at the rear left hand side of engine bay.
50p.

Re: Jx glow plug query

Posted: 20 Jul 2014, 20:12
by what2do
Thanks chaps, will be my first job in the morning - I hope it's nothing more than that, we'll see!!

Re: Jx glow plug query

Posted: 20 Jul 2014, 20:28
by what2do
Blow me, just been out and checked the fuse - all good. Turned the ignition on and the yellow light illuminated? Tried it a few more times, each time, it illuminated without fail. Turned the key and the van fired up like it normally does.

Good and bad really. Chuffed that it's back to normal but we all that an intermittent fault is the worse type!

Any suggestions, relay, earths???

Thanks. Mitch.

Re: Jx glow plug query

Posted: 20 Jul 2014, 20:45
by itchyfeet
User error? :D

didn't fill it with petrol or gas did you?

Re: Jx glow plug query

Posted: 20 Jul 2014, 21:51
by syncronized
When its very hot weather I don't get the glowplugs heating but I thought that was normal. Are they supposed to heat up regardless?

Re: Jx glow plug query

Posted: 20 Jul 2014, 21:54
by HarryMann
Sticky glow relay? Very hot & humid at the mo. Keep an eye on it. NB. Fusible link is 50 or 55 amps. 600 Watts... make sure it doesn't go anywhere it's not meant to.

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:31
by what2do
itchyfeet wrote:User error? :D

didn't fill it with petrol or gas did you?


If only there were an emoticon for sarcasm and 'duh, why didn't I think of that?'. The worse part was, I was in a pub car park where there were loads of people in the beer garden. My cranking away brought the attention of onlookers and when it did fire up they were smothered with white unburned fuel smoke - pleasant for them, I'm sure!

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:32
by what2do
HarryMann wrote: NB. Fusible link is 50 or 55 amps. 600 Watts... make sure it doesn't go anywhere it's not meant to.


What do you mean?

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:35
by Hacksawbob
It's very tight in the black box, just check the exposed metal fuse is not touching anything else if possible.

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:38
by ghost123uk
syncronized wrote:When its very hot weather I don't get the glowplugs heating but I thought that was normal. Are they supposed to heat up regardless?

I am no Diesel expert, but I thought this was the case, hot weather = no glow plug. Is their a sensor to turn them off in hot weather / hot engine situations ?

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:44
by HarryMann
They come on for length of time based on water temp. But if they don't come on should be hot enough to start... and OP said it took some goid few revs to fire and start.
Also and NMPKT...

...they affect the spray pattern in the Indirect pre-chamber.
I've just replaced 4 that had lost their tips due to running on oil for a few seconds...
So there's a bit more to it... and measuring their low resistance accurately (all in parallel)... requres more than a micky mouse multimeter.

Re: Jx glow plug query

Posted: 21 Jul 2014, 08:50
by HarryMann
So.

The scenario usually is (that can be avoided by changibg them asap)..
..steadily worse starting in cold or damp.
... steadily worn deteriorating starter motor (pinion bushes or field windings)
... maybe battery depending on alternator charge and length of runs.
... slower cranking and intitally occasional fail to start.
... finally biting bullet and replacing glowplugs.
I used NGK ones... instant starting again.

Re: Jx glow plug query

Posted: 21 Jul 2014, 09:36
by Plasticman
worth noting that i had a simmilar issue some time back and the fuse whilst looking intact was cracked and just enough left to make a connection but no more, they are very frail and deteriorate with age so take care,
mm