heater plugs on mercedes 300 td

[snowey]

HI, The no one heater plug will not undo, I am thinking that it will break off if i try to get it out, can anyone help please?.

 

[pikeydave]

Is the engine hot or cold?
If not, replace the ones that you've already removed (it might be a good starter on 5 new ones- if so leave the tight one in there!) and try with a hot engine well soaked in a penetrating oil.

 

[Ellsy Tanners]

Yeah, you need to get it at full operating temp, then some oil and hope for the best.

Good luck

 

[Frontstep]

My tips for removing seized heater plug
Wire brush scrape as much crud out of way
Lash penetrating oil on offending item
Wire brush scrape more crud out of way
Use tight fitting socket and T Bar
Whilst engine is hot spray plug with freezer spray a lot !
A short length of pipe insulation is very useful.
Turn plug carefully to tighten first by as small an increment as possible
Keep lashing penetrating oil on most of it will evaporate but it gives you some help
Do not attempt to do anything other than "rock" the plug in and out by the smallest possible amount
Hopefully you will now be removing plug but remember back and forth all the way out
Clean thread with tap hoover out sellotape pipe on end to remove crud.
Have a biscuit
Replace plug with heat proof ant-seize compound
Tell her indoors you have just rebuilt engine, tosh but she won't be listening any way.

 

[turbopete]

everyone suggests a hot engine for this job. and yes it works. the problemthough, as ive said before when someone had this problem, is removing the inlet manifold to access the heater plugs without 1.burning yourself on various hot items you work near, and 2. you have to be quick removing the inlet manifold otherwise the engine cools too much!

 

[Frontstep]

gloves and masking tape cloth on arms

 

[turbopete]

now why didnt i think of that?.......