Glow Plugs

[phoneman(ret)]

Hi,

 

Another topic, 

 

About three years ago, a service showed up one failed glow-plug. Got some useful advice on the forum and changed all four (Bosch). Hard to get out (warm engine) and even harder to get back in !! They didn't all go in same distance (within a turn) due to very nervous of snapping plug.

 

Now another one has failed (number 4 this time, last time number 3). Have got a good quality socket to fit the plugs, but is there any form of lubricant I could use the ease their entry ? or should the engine be at normal operating temperature ? Should plugs last longer, or have I been unlucky ?

 

The indy that has done servicing for a number of years, I believe,  cleans the threads out before fitting new plugs. Would not doing anything lead to problems with the failed plug ? Gone through 2 winters on three plugs and never any problem starting (nice heavy duty Varta battery).

 

Cheers,

 

Lloyd

[skodacarman]

From Haines manual: Great care is needed when inserting plugs as tips must not contact any part of the cylinder head or they may suffer damage. You must use a torque wrench. Set torque to 15 Nm. The threads must be clean if you're reusing plugs.  Do not lubricate the threads, as this will result in a wrong torque reading.  Skoda insist that ECU must be checked for any stored glow plug faults.  If any are found do not re-start the engine.

No mention of need for hot or cold engine.

Hope this helps.

[chrisund123]

I can't vouch for VW engines, but on my previous car I used copper grease on my glow plugs after hearing horror stories of snapping off in the head.

[SuperbTWM]

A while ago somebody mentioned glow plug reamers on the forum. These are to be used to make sure there are no carbon deposits around the tip of the glow plug. It may be worth trying to make sure this isn't the reason why they were so hard to remove/replace

[phoneman(ret)]

Thanks for the information, will leaving a failed glowplug in cause any problems ? 

 

As for torque settings, I don't think that any of the plugs would have gone in at that value ! Looks like I was lucky they didn't break !

 

At the last change, none of the plug tips were very sooty, no visible difference between the failed plug & the three good ones.

 

Would a carbon build up cause a plug to fail ? and would any long term fuel treatment (Red X) help.

 

Lloyd

[skodacarman]

If they won't go in at the required torque, I would say it is a sure sign that the threads and/or seats are fouled.

 

Cars get put together in cleanliness conditions like an operating theater,  we then have to maintain them under cow shed conditions!