250TD GLOW PLUGS-Easy To Change?

[mar96]

Hi there, I've just acquired a c class 250TD.
Are the glow plugs easy to get at and change?
A horrible friend of mine says I'll have to get one of the manifolds off
to replace them.
How do I test that a plug is working-I have a multimeter.
Many thanx. mart

 

[SilverSaloon]

your friend is correct assuming you have the 605 engine

you may be able to access 1 or 2 of them without using a bendy socket set but doubtful unless you've removed them before and applied copper grease to aid future removal....

you can test with a multimeter by following this how-to on the relay.

be careful - they can snap in the head on removal if you dont take care

Mercedes Diesel Glow Plug Repair

 

[Supacool1]

If you do remove the intake manifold get some new o-rings from MB as the olds one will be flatted!

 

[mar96]

your friend is correct assuming you have the 605 engine

you may be able to access 1 or 2 of them without using a bendy socket set but doubtful unless you've removed them before and applied copper grease to aid future removal....

you can test with a multimeter by following this how-to on the relay.

be careful - they can snap in the head on removal if you dont take care

Mercedes Diesel Glow Plug Repair

Hi there,
Thanks for all the advice-it was as you said. I found the manifold was pretty easy to get off. Took it to the garage and they tested the plugs and found the front 3 faulty.
The centre one was already rung off and the front two are jammed, and they didn't want to take the chance of snapping them-fair enough.
My horrible mate says the head'll have to come off-is there an alternate or unusual way I might get them out? Seems I may as well try it, as if the head has to come off
anyway, it's worth giving it a desperate shot beforehand.
Thanx again, mart the glow plug.

 

[mar96]

Hi there, Thanks for the o ring advice. The last person who had the manifold off had used hylomar to seal the flattened rings already. I have now got the snapped glow plug problem. Cheers, mart

 

[peapod]

hi mar 96 , I did mine 100k ago at that time one broke off and I had it drilled out by derrik wells mercedes of stowmarket. this month at 180k no 1 failed. so they last 100k with luck. BE WARNED BEFORE YOU DRILL MAKE SURE THE HARDENED CENTRE ELECTRODE IS OUT OR YOUR DRILL WILL WANDER. If you search glow plugs you will find a post on drilliing them. I advise I ahve not done this job myself but teh routine is break them off dont wind them round and round if stiff best to break them off to avoid wrecking the threads. then pull out the electrode, then drill down to theoutside diam of the threads get this diam from a new plug. next clear the threads, then tap the centre of the remaining hollo bit ( the lower end of the plug) and use a slide hammer to pull it out. As I said, I have not done it myself yet maybe next time, but this is the way. With great care the threads in the head are not damaged. Use copper ease putting the new ones in or they too will get stuck.

 

[SilverSaloon]

the head doesnt need to come off if you've got a broken plug.

just follow this guide:

PeachPartsWiki: Broken Glow Plug Removal

good luck.

if they havn't already snapped, then just try to remove them with LOTS of WD40 and careful pulling/turning. hopefully they will come free. let them soak in WD40 for a good while and also remove them when the engine is nice and hot.

hope it helps

derek

 

[mrsdoyle]

YouTube - CDI broken glowplug repair wo/thread repair kit

maybe ask these guys if they know anyone in your area they have supplied with this tool.
WELCOME TO KLANN TOOLS LTD

 

[SilverSaloon]

remember to put some copper grease on the threads when you refit.... to aid removal next time.