correct spark plug leads for 1969 280SL

[rutger kohler]

I want to find out what the correct spark plug lead ends are for the above car.  It does not have transistorised ignition. I have read the technical manual on this website  and think that the metal ends for the spark plugs themselves are correct?  A photo would be very useful.

[mdsalemi]

Rutger, yes Beru brand metal ends are correct. They are straight, with 1K ohm resistance. They have a "wood screw" end where the plug wire fits in, or rather, screws in. You use these with [near] zero resistance copper core plug wire, also from Beru. The 1K resistance ends are available, but sometimes hard to find, and are not cheap--USD$20-$35 each. Many of our usual suppliers can help you source what you need.

[rutger kohler]

Hurray! thank you Michael, 71 reads and finally a response. My car came with modern blue silicone wires when i bought 4 years ago with about an 8Kohm resistance overall.  Although these work perfectly well there have been mutters at events that they are not quite kosher.  i have read the section on the in the manual , on this site, but it still left me wondering a bit and if i am going to lash out on replacements they might as well be the correct ones.

thanks again
Rodger

[mdsalemi]

Rutger,

Now I'm back home and can even provide a better detail for you.

Believe it or not the plug ends/wire sourcing is not as easy as you might think, particularly if you want to do it correctly, or be true to originality. You can go into any auto parts store in the USA, and what you'll get for maybe $40 or so is a set of wires that are resistor wires with carbon core; a set of rubber ends, and usually one of the plug wires is 90 degrees instead of straight. Will it work? Sure, but not the way it was intended.

You have to search a bit but you can find (perhaps off island, being in your own little world down there) people that will sell you the Beru wire (100% copper core) and the plug ends. Or you can go to some of our retailers listed here and hopefully they'll construct a set for you.

The end connector is like this one: http://www.ebay.com/itm/like/150817196444?lpid=82

I had my set made by a firm in California about 10 year ago, using all the proper ends and wire, at that time it was about USD $150 or so. When a Bosch set was $35 at the local store, this was a bit hard to swallow. Today, however those spark plug ends appear to be over $25 each. So add up all the parts you need to construct a set--and you'll know why a good and proper set might cost so much.

Contact the usual retailers here, see what they offer, and ensure they'll sell or put together what you want. SLS in Germany, or maybe Bud's, SL-Tech would be a good start here in the states.

Be advised that some absolute purists might pipe up here and tell you that where the wire goes into the above connector isn't quite correct versus what came from the factory. Of course. To expect a product to remain unchanged over half a century is just unrealistic. However the above is about as correct as you can find new, short of someone offering new old stock (NOS) and my guess is that would even be more costly!

[garymand]

We were a bit chicken to respond because there are 3 versions on the spark plug ends.  My 250 has all tan plastic stuff shields, the picture in the tech man here shows the 2 later versions.  One has a complete metal jacket and one has a partial metal jacket.  My 280 motor came with full metal jackets.  All use screw on resistor ends and solid core wires, as Michaels says stranded copper wire.  Duplicate the picture.  If you can find a wrecking yard with 80 and 90's the plug covers are used on mamy models.  i've got 8 on my 560.  As you have experienced the resistance is not that critical, but original is 1K ohm on each end.

[mdsalemi]

Well, Gary--he was quite specific as to model and year. I guess the earlier versions don't count for him, and the later ones don't count either as if I read that correct, the factory electronic ignition had 5K ends? (personally I thought that the "factory" electronic was post-1969, but the tech manual has a '69 with "factory" electronic.

Anyway, surely Rutger, a switch to something like I pointed you to is not going to raise too many eyebrows like blue silicone wire sets! 

[KevinC]

I just bought a set from K & K in Michigan. Nice OEM Style.

George sells them too...

http://www.authenticclassics.com/230SL-250SL-280SL-Convertible-113-Chassis-s/1.htm?searching=Y&sort=2&search=plug%20wires&show=16&page=1

[garymand]

Wow,  that is a great price!

 Mercedes 280SL Ignition / Spark Plug Wire set - Copper Core - 1K OHM
Our Price: $79.95
Sale Price: $67.95

I can't show the picture, but it shows all 7 wires with metal jackets and 90 degree cap ends. 
Mercedes Ignition / Spark Plug Wire set
 
" Fits 280SL and other Six Cylinder Models listed below.  Wires are 7mm Silicone Jacket Tinned Copper Core with 1K Ohm Resistance Shielded Spark Plug Connectors and 90 Degree Distributor Wire Connectors.  Spark Plug Connectors are Screw on type and can be removed for installation of wires through Guide Tube on applications where necessary.   Includes Dielectric Grease for Spark Plug Connectors
 Fits:
250, 250C 1970-72 - M130.923
250T 1977-85 - M130.920
280CE, 280E 1978-80 - M110.984
280S 1967-71 - M130.920
280SEL 1968-71 - M130.980
280SL 1967-71 - M130.983 "

[rutger kohler]

Hi Guys, thanks for coming back to me.  I have talked to a NZ guru on MB who served his apprenticeship at the NZ agents when these were coming into the company (and continued to work for them for many years). He has also won several concours events with his cars.  he tells me that the W113's that came into NZ had the bakelite spark plug connestors until the transitorised ignition which was just after my car.  I am going to go with these despite the evidence you have produced about American cars. I like the understate look, but thanks again for your comments, much appreciated.

[garymand]

My 67 has the all tan hard plastic,  I like it better than the full metal jack and have no radio noise.  Not sure why they went so elaborate.  I haven't looked but you might be able to take the jacket off if that is all we can get now.

[KevinC]

George has both...black and metal jacket..

http://www.authenticclassics.com/230SL-250SL-280SL-Convertible-113-Chassis-s/1.htm?searching=Y&sort=2&search=plug%20wires&show=16&page=1

[tel76]

Why such a huge discrepancy in price  $239.95  $64.95  and 54.95 ?

[Garry]

Maybe one came with coil.

Garry

[mdsalemi]

Why such a huge discrepancy in price  $239.95  $64.95  and 54.95 ?

Really, quite simple: the most expensive one, if you read the description, is original Mercedes-Benz parts in the OEM bag. This is what you would get from ordering at the Classic Center, or a dealer. The $67.95 model, thought it does not mention brand, appears to be OEM parts, but not Mercedes branded; this could be custom assembled using Bosch or Beru (or other?) parts that look and act proper. The least costly one does not have the metal jacketed (and costly) plug ends; it has the Bakelite plug ends that Rutger's New Zealand MB Guru says are correct for NZ cars.

It's quite possible that the difference between the MB part, and the next one, is merely the labeling. They both might use the exact same wire and plug ends. George at Authentic Classics is a stand up guy and will be happy to tell you any difference. That the parts MIGHT be 99.99% identical but vastly different in price is one reason why (see other posts recently) there can be vast differences in the costs of a restoration. Some restorers will only go to the dealer for parts, and as that restorer in Harmony PA notes on his website, "markup by 25%". Add that 25% to the discount he receives, and he's making quite a bit on the parts. Think of all the parts this could apply to and you'll begin to see how cost differences begin to add up.

My 1979 BMW 320i had the Bakelite plug ends, but the Bakelite was reddish (like the color of a distributor rotor) not black.