Author Topic: 280S Ignition Troubles  (Read 211 times)

rob280

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280S Ignition Troubles
« on: 26 April 2019, 03:35 PM »
Hi All!

I've owned my 1976 280S for 16 years now. The point ignition was always a PIA. I then bought a Bosch magnetic distributor from a fuel-injected M110 engine and hooked it up to a MSD, it ran fine for over 13 years . Now here in the past year and a half  I have been through 3 MSD units, they do not seem to be of the same quality. I spoke to a friend of mine who owns a hotrod shop and said I may be able to wire the Bosch distributor directly to the coil. I tired it and it did not work. My question is, can I do this or do I need and ignition box? I f so can I just wire up the original system that came in the W116's with electronic ignition. I know I will need to use the solid core wires that came with the car and removed the carbon core MSD recommended. I even bought another Bosch Distributor online, so I know that's not the issue. I'm thinking the original system would be the way to go since they seem to be trouble free. Any help would be greatly appreciated.

ROB
1976 280S
300SEL 6.3 (Someday)

irvine

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Re: 280S Ignition Troubles
« Reply #1 on: 27 April 2019, 02:46 AM »
Have you looked at the pertronix ignition system.
I’m thinking of using it myself, seems to get good reviews.


Neil.

TJ 450

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Re: 280S Ignition Troubles
« Reply #2 on: 28 April 2019, 06:14 AM »
Back when I had a 280S, is swapped the whole setup with one from a K-Jet 280SE. The only issues I had were setting up the coil as it runs at a lower voltage (blue coil), hence the two ballast resistors. I think I had it running at 6v the whole time. The risk of running the black coil is that it may burn out the transistor over time. Running the blue coil at a continuous 12v may cause it to explode, particularly if you accidentally leave the key in Pos II by accident.

With the magnetic pickup, yes you need the amplifier module to switch the coil.

Tim
1976 450SEL 6.9 1432
1969 300SEL 6.3 1394
2003 ML500

rob280

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Re: 280S Ignition Troubles
« Reply #3 on: 29 April 2019, 09:59 AM »
Tim,

I figured the distributor would have to be wired to an ignition box. Do you have a wiring diagram for hooking up the OEM coil, distributor, resistors, and ignition box? Also, would you have the part numbers? Thanks for your help, the ignition system off a K-Jetronic seems to be reliable.

Rob
1976 280S
300SEL 6.3 (Someday)

ptashek

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Re: 280S Ignition Troubles
« Reply #4 on: 30 April 2019, 11:42 AM »
Tim,

I figured the distributor would have to be wired to an ignition box. Do you have a wiring diagram for hooking up the OEM coil, distributor, resistors, and ignition box? Also, would you have the part numbers? Thanks for your help, the ignition system off a K-Jetronic seems to be reliable.

Rob

Does this help?
https://www.circuitlab.com/circuit/5ag5z6/mercedes-benz-w116-ignition-control-circuit/
1993 "Pearl Blue" W124 280TE
1979 "Icon Gold" W116 450SE (history, resto)
1977 "Milan Brown" W116 350SE (parted out)