spark plug question

[mdsalemi]

quote:Originally posted by merrill

Michael,
so, even if I had the aftermarket set, should the wire & connector resistance for the #1 cylinder still be higher than the rest?

the #1 connector is at a 90 degree angle while the others are straight.  Another difference is the #1 connector is red and there is a scrw on the connector that the wire goes onto.

the rest seem to be molded ends and with the exception of the metal cover are black in color

Matt

Matt
66 230 sl - "white"
78 300 D - Blue
98 C230

Matt,

You can check with the normal suppliers, but you can get the spark plug ends individually.  They should all be Beru or Bosch, all be straight, and all be around 1K ohm resistance.  That's the resistance for the radio supression.  They have a metal jacket over rubber, so they look substantial and made of metal.

The screw you speak of is normal for some connectors; the wire is cut flush, and the connector is screwed up into the wire and this screw makes contact with the conductor.  At the cap end you usually see the insulation cut back, the wire (about 1/2") brought up around the insulation, and then a fitting crimped on, making contact with the wire and crimped into the rubber.  You spoke of red; there are wire sets out there, Bosch in particular, that have all their ends made of red bakelite plastic.  My old 320i had this kind of wire set as standard.

You can buy the solid wire by the foot, too.  Here's one place--and only one place--that sells all the little fittings, spark plug connectors, boots, etc.  Do a little sleuthing around their site and you'll find what you need.  I saw all the little fittings for the distributor cap, the wire, and a selection of either OEM, Beru or Bosch spark plug connectors.  I've never bought from these guys, but they seem to have this standard interface that so many other places have.  Your usual parts suppliers should be able to help.

http://www.prostreetonline.com

Here are two more places that have the connectors:

http://www.discountmbparts.com
http://www.stopshopanddrive.com

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[merrill]

So, received new spark plug wires and bosch WR 9 DC plugs from K and K today.
verified all plug gaps and wire ohms before installing.

installed both and no more stumbling!!!!!!!!

set the timing to 31 degrees at 3000 rpm (I konw it is a little advanced, will retard it tomorrow)

took the car for a spin and what a nice ride!

now to torque the head, check the valves and double check the co2.

matt

Matt
66 230 sl - "white"
78 300 D - Blue
98 C230

[rwmastel]

quote:Originally posted by merrill

So, received new spark plug wires and bosch WR 9 DC plugs from K and K today.

Is that a resistance spark plug?

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[merrill]

Rodd,
according to the bosch web site, the R = wirh resistance suppression

when I look up the 66 230 sl the web site refers to these plugs

4016 PLATINUM PLUS GAP=0.032"
4216 PLATINUM GAP=0.032"
7500 SUPER GAP=0.032"
7900 SUPER PLUS GAP=0.032"

Interesting that the WR9DC is part 7512 which is not referenced on the bosch web site.

hmmm,
matt


Matt
66 230 sl - "white"
78 300 D - Blue
98 C230

[rwmastel]

Bosch probably doesn't list it because we don't use "R" plugs on our SLs.  Also, "9" is pretty hot, but I've read that people use them and like them, specially if their car is running rich all the time.  I think "7" is most common.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[merrill]

Rodd,
I took 7's out,  what is interesting Is when I ordered the plugs and wire set from cheryl at K and K she "knew" exactly what plugs to sell me.

I mentioned the NGK's that have shown up in other posts and she would not hear it.   Since I had purchased new coil, condenser, points, capacitor, wires from K&K I figured they would know the proper plugs to sell me.

As a note, the car runs great with the 9's and when I pulled the plugs today (after 200 km) they had some carbon but it wiped off easily.

matt

Matt
66 230 sl - "white"
78 300 D - Blue
98 C230

[Bob G ✝︎]

I have a question :
I purchased a set of orginal copper corespark plug wire set from Van Dike many years ago. this is thefactory set of ignition wires for the 280SL. I have the Bosch coil wire because the coil wire was not offered in the kit "strange" I have the factory stock spark plug wires Bossch I got from BAP-GEON and the red top coil which I understand is 250SL. I am not quite sure what ballast Ithink it might be 1.8 .
I do notice a carbon problems with my plugs and am not sure this is just a tune up setting oran ignition component problem? could you suggest what to look for ?
Also the distributor is a later alumiumn model. I am replacing it with a rebuilt Bosch 09 thanks to Dr. Benz
Bob Geco

[ja17]

Hello Matt,

All the "WR" series Bosch plugs are resistor plugs.  The ignition on these cars was originally designed for non resistor plugs. Your car should run ok with resistor plugs but you are adding another 5,000 ohms resistance to each plug wire circuit.  This may not cause any problems at present, but down the road you may have ignition failure sooner.
Using non resistor plugs may be an acceptable compromise to some. If you are using a modern ignition systems with higher voltages than original, it may handle non-resistor plugs better also.

I have heard Bosch is phasing out the non-resistor spark plugs.  Other manufacturers will continue to produce non-resistor plugs I assume.

Joe Alexander
Blacklick, Ohio

[merrill]

Joe,
so,
based on your post below would either of the plugs below be ok

NGK BP5ES
4016 PLATINUM PLUS GAP=0.032"
4216 PLATINUM GAP=0.032"
7500 SUPER GAP=0.032"
7900 SUPER PLUS GAP=0.032"

Right now the car runs super smooth, and thus far I am very happy with the way the motor is running.

matt

Matt
66 230 sl - "white"
78 300 D - Blue
98 C230

[Vince Canepa]

The BP5ES is too cold.  BP6ES, gapped at .032" are what NGK recommends.  BP9ES are awful hot if you run hard.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[J. Huber]

quote:Originally posted by Vince Canepa

The BP5ES is too cold....

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

Hi Vince. I don't dare challenge your knowledge on such things but what does this mean, exactly. As I mentioned earlier, my car has been running on these for sometime -- with good results.

James
63 230SL

[66andBlue]

quote:Originally posted by J. Huber
....  but what does this mean, exactly.  ..

James,
NGK has a nice write up on that.
See: http://www.ngksparkplugs.com/techinfo/spark_plugs/overviewp2.asp?nav=31000

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Alfred
1966 blue 230SL automatic

[Vince Canepa]

James - The link Al supplied defines it quite nicely (thanks Al).  The net effect of a hotter plug is less deposits forming on the electodes.  Back in the day of leaded fuels, this was very important.  In the US, where we could not run the cars as hard as in Europe, a slightly hotter plug was appropriate.  It helped to keep the lead deposits off the electodes.  These old M-B would develop a high rpm miss after 6,000 miles or so (the spark plug change interval was/is 12,000 miles).  The miss was caused by the lead deposits.  That is why most folks preferred the B7ES over the B6ES.  If the plugs became fouled a good high load run would usually burn the deposits off.

The problem with too hot a plug is pre-ignition - where the electodes don't cool fast enough and they ignite the mixture too early (sort of like a glow plug in a model airplane engine).  All of this really applies to hard driving and most of these cars aren't driven that way anymore.  If anything, I think they are driven too gently, but that also means a hotter plug will work nicely without the pre-igniton problem rearing its ugly head.

I've used the B7ES since 1971 and found them just about right.  In fact, that is what the dealer in Monterey, CA, where I bought my car, installed when they serviced these cars.  I went back to Bosch for a while about 5 years ago, but I felt the car didn't run as well, so I went back.  There was also a discussion about the NGKs in a Road & Track Long Term Test article (around 1971/72) by then engineering editor Ron Wakefield, who owned a 250SL for quite a while.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[J. Huber]

Thanks Guys, I think I get it. I am curious if my car might run even better with the 6 or 7s. I am planning a tune-up for Spring -- so we'll see. Good luck Matt!

James
63 230SL

[Vince Canepa]

Wouldn't you know it - with all this discussion about spark plug connectors, one of my originals went bad.  As I stated in an earlier reply, my car was fitted at the factory with Beru 5K ends.  I was doing my usual winter tune-up/lay-up and found one of the ends at about 10M ohms!  Note - you could not tell it was bad by the way the car ran at idle or under load or in the way it started.

Finding the proper end to match my originals is impossible.  I tried the links supplied by Micheal Salemi and they are no good.  What looks to be the correct part will not work.  They do not have the screw that goes into the end of the wires.  On top of that they shipped 3 that matched - the rest was a mixed bag of mis-matched parts.  Note that these suppliers are getting their parts through World Parts, the same warehouse as Benz Bin, Mercedesshop, etc.

I went where i should have gone in the first place - to my local dealer.  We have a great parts guy and he was able to track the original P/N 000 156 28 10 5K ends through numerous substitutions to the current P/N 000 156 52 10.  The 52 10 is a 1K ohm connector, Mercedes having apparently come to the conclusion that the 5K was not necessary for adequate radio suppresion (I'm sure this will make Dan Caron happy).  The metal jacket is not gold cad, as were my originals, so I had to order 6.  They aren't cheap at about $20 each.  But at least they match, they fit and don't look too out of place.

I can't see any difference in the way the car runs or starts with the 1K ends but then, it ran fine with one bad end at 10M ohms).



Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[mdsalemi]

Vince and others,

[regarding the three links I suggester earlier in this thread]

Moments ago I just tried Stop Shop and Drive, plugged in my year 1969, my make Mercedes, and then Ignition and had no trouble finding Beru ends; their part number is MBZ005175.

I just did the same with Discount MB parts, and followed similar links to drill down to Spark Plug Connector and found 3 different ones.

Lastly, I went to Pro Street Online just now as well, and essentially the same links come up as the previous, with 3 different connectors, one of them Beru.

So, perhaps these are not exactly what you might be looking for, but these are indeed Beru Supressor Spark Plug connectors, from three different sources and these website/links do indeed work.  Again, I tried all 3 just moments ago and found Beru ends at all 3 places.

That being said, if you are trying to match something old, give me a call--you know where to find me.  I think I have the very original wire set from my car and would be happy to help you with a Spark Plug connector.  I don't know if it is exactly what you are looking for, but it might do the trick.  I can always send a photo to you.

You can also try contacting the manufacturer, and I'm sure they'll be able to help:

BERU Corporation
3800 Automation Ave, Suite 100
Auburn Hills, Michigan 48326-1782
Phone +1 248 7540 104
Fax +1 248 7540 113
Contact: eduardo.vultorius@beru.com

I had a wire set made for me using OEM Beru ends; the entire wire set was somewhat less costly then buying all the parts yourself.  My wire set came from Mercedesparts.com, was built with Beru ends on both sides of every wire, and Beru wire, and cost $50 for the set.  Grant you that was a few years ago, 2002.  The only problem with that set was a few of the wires were way too long; Dan Caron shortened them when he had my car 2 years ago.

And of course there is always the dealer, or Caliber (now Mercedes-Benz of Anaheim Hills).

If someone sends you the wrong part all it means is you got the wrong part, it does not mean it does not exist.  I've had wrong parts sent to me from a dealer, even Caliber...

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Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Vince Canepa]

Michael - Maybe you did not understand me.  Those ends you are referring to WILL NOT work.  Instead of a screw that can be threaded into the end of the wire, there is what looks like a brass stud nearly 5 mm in diameter.  I can't figure  out how you would attach them to the end of the wire.  They must be for some other application and incorrectly listed for our cars on the World Parts web link.  Also, they appear to be for 8 or 9 mm diameter wires.  They may be Beru, the websites may say they fit, but the reality is that they don't work on our cars.

My purpose here is so others can avoid the headache of getting the wrong parts.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[mdsalemi]

quote:Originally posted by Vince Canepa

Michael - Maybe you did not understand me.  Those ends you are referring to WILL NOT work.  Instead of a screw that can be threaded into the end of the wire, there is what looks like a brass stud nearly 5 mm in diameter.  I can't figure  out how you would attach them to the end of the wire.  They must be for some other application and incorrectly listed for our cars on the World Parts web link.  Also, they appear to be for 8 or 9 mm diameter wires.  They may be Beru, the websites may say they fit, but the reality is that they don't work on our cars.

My purpose here is so others can avoid the headache of getting the wrong parts.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

Well, one can contact Beru and get to the bottom of it--they are the guys that make the stuff.  I had no issues.  I know of the screw you speak of.  Perhaps this stud is made for some kind of automated manufacturing/crimping process instead of the screw on.  I've only seen screw on types and that's how mine were made.  Maybe they just sent the wrong parts to you.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Tom230sl]

quote:Originally posted by Vince Canepa

Michael - Maybe you did not understand me.  Those ends you are referring to WILL NOT work.  Instead of a screw that can be threaded into the end of the wire, there is what looks like a brass stud nearly 5 mm in diameter.  I can't figure  out how you would attach them to the end of the wire.  They must be for some other application and incorrectly listed for our cars on the World Parts web link.  Also, they appear to be for 8 or 9 mm diameter wires.  They may be Beru, the websites may say they fit, but the reality is that they don't work on our cars.

My purpose here is so others can avoid the headache of getting the wrong parts.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

You know, sometimes posting a pic is helpful for everyone.

[Vince Canepa]

Tom - The problem area I describe is down in a hole and won't photograph.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[mdsalemi]

quote:Originally posted by Vince Canepa

Tom - The problem area I describe is down in a hole and won't photograph.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

Vince is absolutely right--I took off one of the connectors (yes, I do have the original wire set with Beru 5K ends)--and short of some kind of fiber-optic camera there's no way to photograph what's down in that hole...I did contact Beru and hopefully they'll be getting back to me on their catalog items etc.

Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[ja17]

Hello,

Some later MB cars had spark plug wires with crimped on machine screw ends. Likewise the shielded spark plug connectors had machine screw threads. These are not the same as the originals.  However they may be listed as a "fits all"  replacement set. In reality, if the manufacturer  makes the wires long enough, it work on almost anything but fit correctly on almost nothing.

Joe Alexander
Blacklick, Ohio

[Benz Dr.]

There are two basic types of spark plug terminal ends.

The type we are concerned with use a length of spark plug wire that is simply cut off at the end. The plug terminal has a threaded screw at the bottom of the hole where the plug wire is inserted. All you do is push the wire in and turn the connector until it threads into place.
The second type is for more modern cars. This type has a treaded end right on the end of the spark plug wire. The spark plug terminal has a female thread at the bottom of the hole where the plug wire fits into.
You would find this type of system on a 380 SL.

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org
  1 877 661 6061

[merrill]

so, I was talking with cheryl at K&K today and I just "had" to ask why she sold me WR9DC when on their web site they sell  WR7DC's.

cheryl told me that in her discussions with gernold at sl tech it was found that the sl's would have a lot of carbon build up.

gernold uses the wr9dc's to help prevent the build up.

just some feedback

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

[rwmastel]

Both of those part numbers have that nasty little "R" in them for "Resistor".  I thought we were not supposed to use resistor plugs in our Pagodas?

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420