Anyone having to pre-heat their 300tdi *three* times each morning??

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i'd never thought of that b4.. always started it as soon as light goes out.. thought the heat would soak into the block.. but i suppose thats what needs to happen.. if ya just heat the air, it will be blown out of the cylinders as soon as ya turn the key.. its the block ya need to warm really..
 
AFIK They come on for about 6 seconds, the light goes out then they stay on for another 6 seconds, both timings are altered by temperature of water in block.

I have noticed my light takes a good 2-3 seconds longer to go out now its cold.
 
but how do they aid initial combustion by glowing red hot? does the timer go off when they get to temp and they then release the heat into the air an fuel mix as it enters the combustion chamber? in which case youd be better starting when power is still being sent to the heater plugs surely.. when the light on the dash goes out is that the indication to start? i aint got a handbook wiv my disco. only had it a couple of months..
 
They are a very simple system, all it does is glow red, when the fuel spray hits it, it vapourises and will ignite much easier when required.

Yes, the time to crank is when the light goes out, according to the handbook.

All the timings are done in the glowplug relay i think.
 
oooooh....... didn't know about the "cold start procedure for the 300TDi"!

I'll try that tomorrow

Interestingly, this morning (at minus 2 or so), I preheated it once, left the ignition on for 10 seconds after the preheat light went out, then turned the key and it fired instantly.

Do the preheaters stay on even after the preheat light has gone out??

yes if you check with a meter on the glowplug rail ,you will see power remains on for quite a long time-on my old peugeot half power was maintained on the plugs for several minutes,to aid warm up-remove the power and the engine would die-would think landy's are similar
 
on our fourtrack you can hear the plu relay clicking in and out for a minute or two after a cold start... it supposed t make the warm up a bit smoother . we had a set of ngk plugs in a megane... they didnt last a full 12 months before two of them had died.
 
already been described how it works. (davek)
noticed it first when i was sorting abs codes, flicking ignition on and off while drivers door was open.
interior light would be on, hear relay click that turns dash light off, hear seond relay click and interior light glows a bit brighter as plug supply is turned off.
wont be noticable with engine running as alternator compensates for it.
just a little summat to watch for all you 2/3 timers of heater plugs!
 
Mightily pi55ed off, mine wouldn't start Sunday so wrongly assumed it was the battery.
100squid spent at halfrauds and still won't start, the motors cranking over veery slowly.
So then I found this thread - first Ive heard of preheating, and to top it all orf I can't get around the immobilser now!!
Am hoping it's due to leaving bonnet up whilst trying EKA code, 3wrong attempts and it locks out for 30mins.
Shall give it half an hr and if EKA code works have a go at preheating.
Stoopid question, but I guess the glow plug light on dash us the one which looks like a coil/spring affair (yellow symbol)?
 
Go straight to engine block not chassis, if its better then its the engine to chassis earth bad.

Not sure but you can supply the fuel solenoid direct from battery to bypass the alarm for a test??

If you are going to do that run another lead from battery positive to glow plug rail(CAREFUL-DO NOT SHORT AGAINST ENGINE METALWORK)-wait 5-10 secs,then crank over
 
as an update, i fitted new plugs from devon 4x4 yesterday. Left it overnight and it just started on the button... hurray
 
So... anyone else or is it just me??

If it is just me (i.e. it's not a generic Land Rover thing), what do you think the fault is?

If I preheat just once or twice, it will start eventually, but takes many seconds of turning over on battery before it fires!

Two preheats is better than 1 and 3 is better than 2 though, so it's not intermittent, it's just crap!

Sorted!

Always get good glow plugs, Bosch (OE) or Beru, they will reach full working temp within the time the glow plug relay provides them. Cheapy £4 a pop ones and old ones take an age to even start to look warm, so by the time the relay shuts down the plug is still not hot enough. My bosch plugs will be RED hot within about 4 seconds and going into runaway reaction within about 7.

Expect to pay £9-10 a plug for good ones.

Also - try decking the throttle on starting, on the Bosch injection pump this will work, unlike the Lucas pumps.
 
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