# Glow plugs and carbon build up



## BillCreer (Jan 23, 2010)

I had my van MOT'd last weeks at the small garage I've used for about 30 years. I know the two owners very well now and while I was waiting for my MOT to be done I overheard someone receiving the news that they had a £600+ bill for replacing the glow plugs.
When I asked what made it so expensive they explained that there was quite a common problem now with carbon build up on glow plugs which makes removing the plugs almost impossible.
When they come across this problem they have to get a specialist in who uses very special equipment. He has to drill down the centre of the stuck plug and insert another tool to cut away the carbon but even after this has taken place there is a good chance that the thread will be stripped off on removal.

Lesson is, I guess, is to remove and inspect your glow plugs regularly.


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## ingram (May 12, 2005)

Well, I don't know about glow plugs ( how many does a modern common rail diesel engine have? ) but this is a problem with injectors. This may not apply to all makes / engines but some injectors are held in by a clamp, rather than being screwed in. The seal is similar to a spark plug washer. These can leak possibly causing burn through and causing a carbon build up around the injector. This then seizes the injector into the cylinder head.

My son's Merc Vito suffered from this recently. He is a mechanic but had to get the 'specialist' with special tools to remove one of the injectors.

Harvey

ps. I think that the injectors were about £100 each but a lot cheaper than those from a 'main dealer'


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## SomersetSteve (Oct 4, 2011)

I'm now feeling that the £90 I paid to get mine changed was a lot less than it might have been...


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## spatz1 (May 19, 2011)

interesting....

but why would anyone change them all when you can test and identify the one thats gone with a simple + ve wire ???


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## SomersetSteve (Oct 4, 2011)

I only had one working! Seemed sensible to change that one as well whilst doing the job.


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