300Tdi - Slow start in cold weather - New glow plugs needed?

And mid 20's here, not a cloud in the sky, Xmas dinner was turkey sandwiches on the beach. I can feel a couple of days venturing offroad into the back country moving towards the top of the agenda - all I need is to find another like minded individual (the bloke I usually go with is freezing his bollocks of in Wales) and I'll be off.

On or around Fri, 30 Dec 2005 09:00:45 +1300, EMB enlightened us thusly:

whereabouts? tell 'im to call in for a coffee...

Update:

All 4 glow plugs are dead as a dodo. I've only had one of them out and it has big grey burnt bit on one side of the tip. I can't get my test light to light up when connected between the +ve battery terminal and the top of the glow plugs - so the plugs are apparently not earthing.

Have tried a few shops but nobody seems to have any of the right type (and it's New Year's Eve afternoon so most places are shutting now).

No hurry though, as even at -3.5 deg C it was still starting eventually last week.

Thanks for helping with the diagnosis.

Judith

Ahem.

Richard

I wasn't ignoring you, Richard.

A colleague at work only managed to change two of the plugs of his

200Tdi so he's given me his spares. I reckon 2 out of 4 is better than none so will fit them this weekend.

Judith

Don't. Get a full set. As each plug blows the current draw, and consequently voltage drop lessens which leads to excessive voltage to the remaining plugs causing them to either fail or have a significantly shortened lifespan.

Seems to be a common complaint - neighbour had a similar issue with his car[1]. Gave up and tasked the local tech with the job of fitting the remaining two.

[1] blue, diesel - possibly made in france

On or around Fri, 06 Jan 2006 13:14:14 +1300, EMB enlightened us thusly:

not on a parallel-wired one, though? they all in theory get 12V nominal. Mind, if the power distribution is not balanced there may be a minor effect that the one at the end of the line gets less voltage.

The effect on battery voltage is minor, or should be, and in any case the plugs are mean to be able to handle 12V.

There's also the point that on a TDi, 2 plugs are probably enough to make sure that it starts...

Still good practice top replace the set though - it's like spark plugs, no point in changing part of a set, except if one gets broken or something.

That and the drop in the feed.

Steve

Check the voltage rating on the glow plugs - most '12V' ones are rated at between 7 and 11 volts. The voltage drop in the wiring brings the voltage at the glow plug down to this level - reducing the current draw (eg a dead plug) lessens the voltage drop and thus increases the voltage across the remaining glow plugs.

A quick test on my Hilux this morning shows 10.2V at the glow plugs, removing the connection to one glow plug raised this by 0.5V which has got to lessen the lifespan of the remaining plugs.