changing spark plugs on E430 - PeachParts Mercedes-Benz Forum

#1 02-13-2003, 08:35 AM

Are there special tools needed to change the spark plugs on an E430/M113? I'm assuming I'll need a boot puller as the wires are encased in metal, or do these metal boots twist off? Is there a special spark plug wrench also? "Engineered like no other car in the world" - you bet!!

placo1 · #2 02-13-2003, 01:10 PM

You'll need the right socket wrench to pull install the plugs.

I'd also recommend looking in your owners manual for the gap setting of the plug. You'll also find the torque setting on the same page which tell you how much to tighten the plugs. Get a good torque wrench capable of handling the lower torque settings.

#3 02-13-2003, 01:12 PM

Thanks for the help. Do you know if the plug boots twist off or can be pulled off? They're encased in metal...

placo1 · #4 02-13-2003, 01:21 PM

Honestly I don't know, I haven't seen your engine setup. Maybe someone else can chime in on that one.

I changed mine last weekend and my ends were made of rubber with a metal center. They pulled right off with some force and pushed back in just the same. They weren't easy to remove but they weren't difficult either. No tools were required to remove them.

If you do get a boot puller make sure to spend the money and get a good one. I remember buying a cheap one many years ago that tore up the rubber of the boot. I had to replace half the boots!

Good Luck

S-Class Guru · #5 02-13-2003, 02:45 PM

Just be careful and pull straight out on the metal boots; they have ceramic inserts and can break. Removing them while still warm seems to work better. I found that a good straight jerk while holding the metal portion works best. If you do break one, the wire just screws into the end, and the insert can be replaced without replacing the wire. Don't pull on the wire, of course.
When replacing them, use a dab of dielectric grease on the end of the plug, and also use some anti-seize grease on the other threaded end of the plug while you're at it.

cerbomark · #6 02-13-2003, 03:42 PM

CMBENZ, Let us know what kind of a job it turned out to be with any helpful hints. How many miles were on you old plugs and what did they look like. Maybe I ll try mine when you report back, Thanks

#7 02-13-2003, 03:53 PM

So you want me and my car to be the guinea pigs eh? I'll let you know - I have to buy 8 more plugs as there are 16 on the car - two per each cylinder.

Gilly · #8 02-13-2003, 04:10 PM

The tool MB advises to use to remove the plug wires is a 17mm open end wrench with a real severe offset. The original use for this wrench was to adjust valves on an M110 engine. It is inserted into the skinny part of the metal tube, then the wrench can be pried against the valve cover to lever off the plug wires.

Gilly