vorstellung 450sl from California 1979 with TSZ-4

Hello,
New member here, from California with some ignition issues. Thank you for this site, I could download the correct testing procedure, the Mercedes CD manual that I have did not have the correct testing procedure for the R107 / 450sl 1979 with 46Kkm/ with he breakerless distributor.
In my case once the misfiring started, I pulled over and let the engine cool... it was a hot day, not even 20C, but the coil was very hot. I managed to drive home stopping every 10min. I installed one of the Jeep coil and it ran fine, albeit the specs are different. The last test drive was good but after 20min the misfiring and loss of power was very noticeable. Let the coil cool for 10 min while checking resistance numbers and realized that my voltmeter is not good enough to measure low resistance, so I will use a differential method. The engine restarted and had plenty of power to go up our many hills in San Francisco. Now I am back to testing the various output because I have the right instructions. Now I will be able to so some tests when the ignition starts to fail after 5 to 20 min.

I was lucky to find 2 450 at the local junkyard and retrieve 2 ignition box

I hope that google translate did not make too many awful mistakes

Cheers
Michel

Hallo,
Neues mitglied hier, aus den USA. Vielen dank für diese seite, ich konnte das korrekte testverfahren herunterladen, das Mercedes-CD-Handbuch, das ich hatte, nicht das korrekte Testverfahren hatte, weil unser R107 / 450sl 1979 mit 46Kkm / den breakerless Verteiler hat.

In meinem fall, als der Aussetzer losging, fuhr ich los und ließ den motor abkühlen ... es war nicht heiß, die außentemperatur 20 ° C, aber die spule war sehr heiß. Ich schaffte es alle 10 minuten nach hause zu fahren und anzuhalten. Ich habe eine der Jeep-spulen installiert und sie lief einwandfrei, obwohl die technischen Daten unterschiedlich sind. Die letzte Probefahrt war gut, aber nach 20 Minuten waren fehlzündungen und stromausfall sehr auffällig. Diesmal hörte ich nicht auf und schaffte es kaum nach hause. Lassen sie die spule 10 Minuten lang abkühlen, während sie die widerstandszahlen überprüfen, und stellen sie fest. Mein Voltmeter ist nicht gut genug, um einen niedrigen Widerstand zu messen. Daher verwende ich eine Differentialmethode. Der motor sprang an und hatte genug kraft, um die vielen hügel in San Francisco hinaufzufahren. Jetzt bin ich zurück, um die verschiedenen ausgaben zu testen, da ich die richtigen anweisungen habe.
Jetzt kann ich so einige tests machen, wenn die zündung nach 5 bis 20 min ausfällt

Ich hatte das Glück, 2x 450sl auf dem örtlichen Schrottplatz zu finden und 2 Zündboxen zu holen

Ich hoffe, das google translate nicht zu viele schreckliche Fehler gemacht hat

Grüße

Michel

Hi Michel,

there is absolutely no need to translate to German. We understand and communicate in English very well.

Welcome to jetronic.org and if you wish you can also have another look into my 107 SL website sternzeit-107.de . There we have much more German writing. But I'd love to see some more English writing there as well.

Hi,

am I right that the 1979 450SL is no D-Jetronic? Is, at least, the ignition system similar?

Best regards,
Recardo

Hi Recardo,

absolutely NOT!

450 SL KA-Jetronic has a breakerless igntion system TSZ-4 with an inductive sensor. 450 SL D-Jetronic always has a breaker even that is already transistorized named TSZ-k (k stands for Kontakt). They are totally different. The big problem is that the late unfied TSZ-k ignition module and the early TSZ-4 igntion module are compatible in connectors. Mercedes-Benz uses that in W114/W116 from the beginning (exception 250 CE) and in 107 as of late 74.

Dear Volker,

thanks for your explanation. I am always impressed about this incredible knowledge. Good to have you.

Best regards,
Recardo

Hi, it has been a long time to update my post, I hope that everyone is fine.
I found 2 extra switchgear at the local junkyard and the engine started in the driveway, for a few minutes run. One of these switchgear is installed, and I have another one ready if the engine stops running to do test and eventually do a quick road side swap.

Also in case the switchgears from the junkyard have the same issues I retrofitted a MSD CDI box to connected to the electrical system. I disconnected the coil wire and the switchgears plugs, and made a crude connection to the Green wire from the distributor which is a non standard "phono jack" or "radio antenna jack" This will be good for testing but in the future I will make a weatherpack connector if needed.

As soon as we are allowed to venture outdoor, we will take the little car for a drive

Thank you for the wealth of information available on the site, I have made a list of what to look at for the next roadside repair...

Stay safe, well and resilient

Michel