H9DC0 Spark Plugs - PeachParts Mercedes-Benz Forum

stormyc88 · #1 12-24-2012, 10:12 AM

Happy Holidays!

Does anyone know if you can still get the Bosch H9DC0 spark plugs here at peach parts? The link that I had saved as a bookmark was working until recently, now the link brings me directly to this forum.

Also, does anyone know what torque setting should you use when installing the plugs with anti-seize compound? The shop manual says 15ft-lbs, but that is without anti-seize compound.

Thanks much!
-Chris

Gilly · #2 12-24-2012, 03:44 PM

I don't recommend using anti-seize, just torque them to the correct spec and they will come out just fine without it.
In general I don't recommend anti-seize for anything other than keeping the tube of anti-seize filled.
But if you do use it, the plug is being torqued up directly agains the head so I see no reason why the torque value would be any different, just because your threads are slimed up with that anti-seize junk.
I did a search here for H9dco and came up with nothing, here is a link, good luck in finding them, I guess hard to get non-resistor plugs now.
Non resistor spark plugs

As an alternative you could get resistor plugs and put non-resistor plug wire ends on your current wires possibly? Or maybe that would require new wires.

stormyc88 · #3 12-24-2012, 07:13 PM

Thanks Gilly, I have read that you're supposed to use different torque values when you use anti-seize compound versus no compound. Just curious about others' thoughts on that.

Anyways, Happy Holidays!

Gilly · #4 12-24-2012, 07:22 PM

I can see where it would make it easier to turn in/out, but the torque value should remain the same IMHO. I would again also maintain that in a properly maintained engine the antisleaze is totally unneccesary.

lsmalley · #5 12-25-2012, 12:34 PM

H9DC0 are available at the dealership. It might cost you a bit more, but at least you are getting the correct plugs.

teezer · #6 12-25-2012, 12:43 PM

well, i'm a believer in using anti-seize on plugs on engines with aluminum or alloy heads where just a little dab will do ya

over the years have pulled alot of plugs with the head threads on them and see no downside from using anti-seize

btw ~~~ have over a 100 bosch german h9dc plugs available

PM me if interested

..

stormyc88 · #7 12-25-2012, 04:34 PM

Quote:

Originally Posted by teezer

well, i'm a believer in using anti-seize on plugs on engines with aluminum or alloy heads where just a little dab will do ya

over the years have pulled alot of plugs with the head threads on them and see no downside from using anti-seize

btw ~~~ have over a 100 bosch german h9dc plugs available

PM me if interested

..

Definitely interested, I just sent you a pm. Merry Christmas!

rayhennig · #8 12-26-2012, 11:25 AM

Quote:

Originally Posted by lsmalley

H9DC0 are available at the dealership. It might cost you a bit more, but at least you are getting the correct plugs.

What's wrong with other brands? I've been using Beru for ages and have just installed a set of NGKs.

I can't imagine getting in a state of tension looking for Bosch.

RayH

DieselPaul · #9 12-26-2012, 01:54 PM

They just need to be non-resistor. NGK or Beru is fine as long as they don't have a resistor.

RobertFini · #10 12-26-2012, 11:12 PM

I used the Champion part number shown in my owner's manual; they were about $2.00 each, easy to get at my local NAPA and they work just fine.

mpolli · #11 12-27-2012, 12:00 AM

The rule for antiseize or oil of any kind on a fastener is its OK to put it on the threads but not under the head. The head is where most of the friction occurs upon tightening. As long as you keep it off of the head area then it shouldn't affect the torque too much. There might be a spec somewhere. I would not reduce much on a spark plug. The consequences of it loosening are too serious.

lsmalley · #12 12-28-2012, 10:11 AM

Quote:

Originally Posted by RobertFini

I used the Champion part number shown in my owner's manual; they were about $2.00 each, easy to get at my local NAPA and they work just fine.

I have searched for all the other brands and all are resistors. Even when I came upon some Champion plugs they were not what my manual recommends, which are S12YC, they were S12RYC )or something like that) and my understanding is that when there is an R designated in any manufacturer number of the spark plug it is a resistor in "almost" all cases.

big dog 2 · #13 12-28-2012, 01:46 PM

My local Napa store did not have the non-resister Champions.

DieselPaul · #14 12-28-2012, 01:56 PM

My napa could not get anything suitable for my 190E. A lot of plugs superseded, cross referenced, or came up as "OE" that were actually resistor plugs.

The guys I deal with at napa are really good, we searched for a while even got out actual books... A rarity in today's parts stores.

R in a part number does imply a resistor according to NAPAs book.

I ended up buying what rock auto claimed were their last 6 loose Bosch plugs.

S-Class Guru · #15 12-28-2012, 03:48 PM

You can still sometimes find the NGK BP6EFS or BP5EFS. The "6" is a slightly colder plug, specified for the Euro market (wonder why? Maybe cause they drive faster, or don't have as strict emissions stds?).
Both have been recommended by guys herein.

DG