Spark Plug Wire Routing

[mrfatboy]

Does anybody have pictures or can describe the proper routing of the spark plug wires?  I have seen several pictures and they are all different.  I have even seen the temp gauge capillary wire routed with them in the engine mounted bracket.  I'm not sure if that is correct or not either.

Also, is there a possibility with these cables to have "cross talk" with the cables when firing?  I don't remember reading anything about it but I thought I would ask.

 

[ja17]

You may be asking the question everyone was afraid to ask!  I have seen the factory rout the cluster of spark plug wires above the injection lines and also below the injection lines. If yours is a later 280SL which had the plastic cover on the distributor, the wire cluster had to be routed below the injection lines. A large diameter section of black  plastic sleeve collected and covered the group of spark plug wires as it passed over or under the injection lines. Two black plastic spark plug wire holders are mounted on the "cross over rod" brackets. They each have six positions. The top position is for plug wire #6 then the next down is plug wire #5 etc. Not all the slots in the rear or front holder are used. Yes the capillary tube for the temp gauge is also held in place between the plug wires.

Studying the BBB engine photos closely will reveal a lot of original information. Some factory sales photos are also most likely correct. Some details vary depending on year and model W113 cars.

Good subject to cover. A nice original well fitting wire set looks so good and correct!

[mrfatboy]

"You may be asking the question everyone was afraid to ask! "

LOL.  I would bet money on it!

I'm confused by your comment that all the rear black plastic spark plug slots are filled?  Did you mean all the front slots?  If I fill all the rear slots, wiring for cylinders 1,3,5 would be going all the way to the rear and than back to the front to the plugs. Can you clarify?

Does the capillary wire route directly in the middle (3 holders above and 3 below) of the wire brackets?   

[twistedtree]

I think it's a typo.  I think he means "'not' all the slots on the read holder are used"

Those of us who can't type can recognize our own kind.

[twistedtree]

Oh, that's pretty funny.  I just spotted my typo.  That's "rear", not "read".

[glenn]

More evidence that MB did not build two car alike...   Diversity....

[49er]

I posted this photo of my 280SL taken the evening I drove it home back in '68. Not the best quality photo but might be of help
http://www.sl113.org/forums/index.php?topic=13651.msg93171#msg93171

John

[mrfatboy]

LoL. That's one of the photos that I have been using as a reference. However, I was told it was a late model 280sl because of some other features      If you bought the car in '68 that information must be incorrect.

[ja17]

Yes of coarse, all the slots in the plastic wire holders are not filled. Not sure what I was thinking. #6 wire does start at the top, then #5 etc. I guess I need to go back and fix that post....

Nice original photos !

Notice the fan shroud on the radiator and no AC.  Also notice the two plastic wire ties on the valve cover vent line rubber at the intake. Lastly note that the spark plug wires are routed under the injection lines as a result of the plastic distributor cover.