P38A Oh no not this again...

Evening all,
sorry about this - its another 'my 2.5 DT is difficult starting...' thread.
Ok - Only first thing, it needs a bit of cranking. Then it starts up with a puff of white smoke. Fine for the rest of the day. I've tested the lift pump, its fine. There's 12v going to the glow plugs whenever the lamp is on. I replaced them all only about 18 months ago.
I'm sure its not a fuel problem, it runs fine, the only thing is this need to crank it in the mornings. I've got a feeling I need to get it sorted before the cold weather.
So - a few questions.
Anyone know what the resistance of the glowplugs should be? (mine says 60 ohms, that's all of them still wired together)
Why is there still 12v at the glowplug even after the lamp has gone out( but the engine not started)?
I haven't got a Nanocom. Should I just replace the plugs?
Thanks, as ever, for any help.

Check your spill (leak off) pipes...if they are getting on a bit they can allow air bubbles into the injectors giving difficult starting after being left standing for a while.

The glow plug light has no real time meaning for glow plug heating, you should have a relay which if your getting 12v at the gp it sounds OK I would pull the plugs and test then across the battery I bet its a glow plug issue

Be good to get a Nanocom on it. Mileage? Battery good?

What happens if you turn the ignition on and listen until the pump has stopped In the tank? I know you don't think it's fuel related but it sounds like fuel run back?

Things that I have done to aide cold starting with my derv over the last month.
1, New glowplugs
2, New spilloff pipes
3, 5 rebuilt and 1 new injector
4, A good well charged battery. I'd let it drain by leaving lights on. Put it on the charger at work. Brought it back to life.

The last 2 made the most difference.

Thanks for replies.
I changed all spill pipes a couple of months ago. The battery is good, mileage is about 160k. My intuition (!) tells me it is the plugs
Anyone any idea of any measurements I could do before removing the plugs?
I feel like if I'm going to the trouble of taking them out (manifold off etc.) then I might as well replace them with new...

Not sure about the BM diesel but some glow plugged diesels do an after glow for a few seconds after the engine has fired.

Littelwill said:

What happens if you turn the ignition on and listen until the pump has stopped In the tank? I know you don't think it's fuel related but it sounds like fuel run back?

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I don't think I can hear the pump in the tank. But when I took the pipe off the filter housing it was pumping at a good rate (around 200ml in 10 secs)
I change the fuel filter regularly - couldn't be that blocking the flow could it? Like I say, it runs fine once its going.

What make were you last glowplugs?

G~

gencybay said:

What make were you last glowplugs?

G~

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The guy who did them showed me empty NGK boxes ...
There were a couple of other things which made me wonder about his cred tho'...

plumbfisher said:

The guy who did them showed me empty NGK boxes ...
There were a couple of other things which made me wonder about his cred tho'...

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Would be my starting point.

Wammers of the Grump is fussy on this but he is 100% right.

G~

So maybe I should just get some good ones and change them all?

Yes, but get some decent lube (not WD40) down those threads before giving it welly. The heads break off.



G~

Plusgas or Lever...a good quality penetrating fluid is required if they were not coppa-slipped on fitment....

Having a warm engine can help get the old plugs out too....

Heh, sounds like I will never be getting mine back out again. I forgot to copper slip them.

I think I paid £30 for a set of 6 Bosch plugs.

Bix said:

Heh, sounds like I will never be getting mine back out again.

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You might not need to - aren't Bosch meant to last forever?
I'm hoping that the guy that did mine did at least copperslip them. But if he put crap ones in, do you think that he would care that much? We'll see.
Found some NGK ones locally for 40 quid, so I'm off to get them tomoz. Do the job Thursday maybe. I'll keep you posted. Thanks.

plumbfisher said:

You might not need to - aren't Bosch meant to last forever?
I'm hoping that the guy that did mine did at least copperslip them. But if he put crap ones in, do you think that he would care that much? We'll see.
Found some NGK ones locally for 40 quid, so I'm off to get them tomoz. Do the job Thursday maybe. I'll keep you posted. Thanks.

Click to expand...

Hopefully. At least last long enough until I can park up the bus and strip down the while engine and give it a top to bottom refresh as it is now over 205k on it.

When it came to doing the plugs the most awkward part for me was getting to the last few manifold bolts (really awkward places, but I did it at work so I could use some of their tools) and putting the nuts back on the plugs. A guide online said to put a small but of tissue over the nut then put it on the socket. It worked nicely.

'Morning all,
the bit of tissue over the nut trick works really well, thanks, (along with a long 12mm socket). I've got a Stanley 3/8 drive ratchet that also turns by twisting the handle. A great help too for that bottom rear manifold nut...
Anyway, I must humbly admit that I did the guy who changed them previously a dis-service. They were all NGKs, and he had copper greased them. They came out really easily. Sorry, my cynicism was out of order.
I found two that were not working. Replaced them all, it starts on the button again!
One thing that did bother me was the amount of gungy oily crap in the manifold. Cleaned it out with petrol, and thoroughly cleaned the EGR too. Following advice on here I'd disconnected the EGR a year or more ago. EGR valve is shut ok. Is all this crap from previously when the EGR was working?
But if it is coming from the breather on the rocker cover is there a danger of this going into through the turbo and fuelling the engine?
Can a M51 do this even with all the electronic control it has?