SL-Class (R129) 1990-2002: SL 280, SL 300, SL 320, SL 500, SL 600, SL 60 AMG

SL/R129: leaking seal for rotor adaptor? beads of antifreeze in passenger side distributor cap

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Old Oct 11, 2018 | 09:05 AM
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leaking seal for rotor adaptor? beads of antifreeze in passenger side distributor cap

1992 R129 500SL engine 119.960 looking for blow up pic of parts for ignition rotor adapter seal ? and seal part number if there is a seal that can be replaced..
opened up distributor caps to see if carbon tracing might be shorting out my spark when engine gets hot and found what looks like to be condensed beads of antifreeze? inside the passenger side distributor cap took everything out including the rotor adapter.looks like it sits in a seal, looking for mercedes factory repair diagram of these parts and seal ..

please advise

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Old Oct 11, 2018 | 10:27 AM
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R129.067 (500SL '93), EQE, MGB
What makes you think it is antifreeze? The common M119.960 problem is just moisture and dirt in distributor caps and rotors. Especially if your car's storage is prone to condensation. There is a large red seal ring A0209970548 on both sides.
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Old Oct 11, 2018 | 11:24 AM
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the copious amounts of ?condensation? that I found has an oily feel to it, and it was only in the distro cap on the passenger side of the car, the driver side distro cap was bone dry - the seal you are talking about is the distributor cap sea that seals to the fibeglass cup behind the rotor and the rotor adapter
-- I'm talking about a possible seal behind the fiberglass cup that the rotor adapter passes thru, then attaches to the cam shaft with a 5mm allen bolt.
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Old Oct 12, 2018 | 09:48 AM
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R129.067 (500SL '93), EQE, MGB

17 is the oil seal.
Yes, there is a seal for the camshaft. Pls report back when you find the root problem; I do not get, how coolant could find its way to the distributor.
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Old Oct 12, 2018 | 01:21 PM
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the older guy at the local MB dealership that works on classic MBs like this said there was no seal to be replaced and that condensation is a common problem for this distributor type -- Im thinking now that it isnt antifreeze but that the condensation is a mixture of water and oil vapor that is leaking through that old 26 year old seal into the distributor cap is my guess, because it has access directly into the interior of the distributor cap area from behind the backside of the rear of the distributor cap, that mates up with the cup at the rear that the rotor adapter passes thru, then thru the seal,and is attached to the cam shaft via a 5mm allen bolt.

what I find curious is that the ID of the cam seal sold on many internet sites for this MB is much bigger than the approximate 18-19mm that I measured as the OD of the ignition rotor adapter that attaches to the end of the cam shaft -- I will have to check it out some more -- I dont want to be pulling this seal out if not necessary

is this seal easy to pull out and replace with the valve cover in place -- or does the valve cover need to pulled and the seal pressed in ??

also, where can I get as many diagrams like this for my 1992 500SL ? and is there a repair manual available anywhere? I've scoured the internet for months and cant find anything anywhere -- and the mercedes and bosch books havent been any help as they only generalize about theoretical operations and function but dont get into specific details or mechanics or how to solve problems and repair issues .. thanks
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Old Oct 13, 2018 | 02:29 AM
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Clean your distributors and rotors. Make sure there are no cracks and if in doubt renew. See if that addresses your issue. If ignition misfire, the next usual suspects are high tension leads and coils.
There is no traditional repair manual available for the R129 but this bi-lingual DVD comes close to. The attached picture is from MB Electronic Parts Catalogue (EPC). On the DVD there is also a somewhat limited R129 EPC (plus wealth of other information). This forum and the Internet are also great resources for repair info; search is your friend.
Good luck!
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Old Oct 13, 2018 | 03:15 PM
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https://www.mboemparts.com/oem-parts...0012907?c=az0x
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