Ignition Condenser
 

Hi

Our W116, D Jet, is having starting issues. The engine cranks, but will not fire.

I think the ignition was left on "accessories" for about 10 minutes, which caused the issue.

I've pulled the lead off the distributor (from the coil), and there is a weak spark between the conductor and an earth.

There is no spark at the spark plug, though

I'm thinking it might be the condenser. (the entire ignition system, except for the condenser, was recently replaced by me a few months ago, and she started first time every time).

The issue arose after the car was driven for about 20 minutes, then engine was off for 10 minutes. Car won't start now.

Anyhoo, I was wondering if anyone had the part number for the condenser. I can't see anything on it.

The distributor part number is 0231 306 002 PFUDX6.

Any other pointers appreciated.

Does the car have a white ceramic ballast resistor? Check that for condition and continuity, if failing it will provide low primary voltage to the coil. IMO the condenser is possibly the issue but unlikely.

In normal conditions spark into the cap but none to the plugs is a cap/rotor problem but weak spark into the cap was indicated. Check the rotor for burning and continuity.

yes check your resistor bars , on my Djet I replaced the old ignition with an electronic version, ended the gap/condenser issues . You may want to consider that . One issue with upgrade is that set up for sure does not like the ignition left on
I used the Pertronix 1885
good right up here
https://www.benzworld.org/threads/74-450sl-ecu.1518076/#post-4135440

The condenser was eliminated from all Djets. No need for one, at least on our V-8s. What is your model year and engine type? If Pertronix is available, it would be a good upgrade.

By all means check the two big resistors. On our V-8s, they are 0.4 and 0.6 ohm. Check that connections are clean and not broken.

In particular, check that the (green?) wire that runs from the distributor to a connector in the same area as the resistors is connected and not grounded anywhere.

Also check the connections on the ignition coil are clean and sound.

It could be that the Switchgear (electronic ignition module) is failing. Hopefully not, but if it is, the Pertronix can be installed in a way that allows that to be eliminated.

Good Luck.

as always , good advice Graham, good to see you are still active! Funny thing, was cleaning out the shop today and ran across that old steering box - thought of you:)

back to the thread , had a no start on a 220 - that daggone green wire was grounded out ... go figure

Hi Ron,

I mentioned that green wire because I once had my 107 die on a major highway near us. I thought I had run out of gas. Luckily car died almost right at highway service center. I walked to center, bought a can of gas. Put that in car, but it still would not run :( (I was actually on my way to buy a new cell phone, so couldn't even easily call for help!) In desperation, I opened hood and had a look. Somehow that green wire had come in contact with exhaust manifold. The insulation had melted and it grounded out. In a few minutes I was back on road :)

We had booked for a month at Myrtle Beach starting about now. But my wife had a small medical issue that prevented her from getting medical travel insurance, so we cancelled. I had in back of mind to contact you about that steering box while we were down there. But, thinking about it, other than as a bench rebuild project, I can't see myself changing one of those boxes at my age. Besides, the Lucas snake oil seems to have finally stemmed the small leak I had! I really appreciate you offering it to me, but maybe someone else would like to have it?
Cheers,
Graham

Mine shorted out because I routed the wire wrong during a distributor upgrade...


and .. I understand, I love Lucas products since I have been attending NHRA drags in indy , the cars are beasts and all the pit crews swear by Lucas products. :)
Hope you wife is OK , and as far as the box, Ill let it be known I have it , like you , as I age big projects are less desirable, but until it finds another home your name is on it (literally) lol

Thanks gents

I've replaced both resistors and still no start

I'm not sure I'm following re the green wire. Any photos available

I'm waiting for a new condenser, but in the mean time, is there anything else I can check

I'm pretty sure the ignition was left on for a whiles and that's when the problem started.

From some other posts, it looks like you are in Australia? If so, likely a ROW car that many here would not be familiar with? From distributor you quoted, it seems it is an M110 6-cylinder.

I mentioned that condensers were eliminated or removed, but you ordered one? They were completely removed from North American Djets. EPC for M110 does still show a part number whether it is needed or not!

Post the model, year and engine type so we are all on same page. I described where the green wire is in a previous post. Maybe this will helphttps://i.ebayimg.com/images/g/lyEAA...OU/s-l1600.png

Many thanks for the reply

Yep, I'm in Australia

My first post has a pic of the distributor showing a capacitor

The wire into the distributor, is spliced with another wire, but I'm not sure what for. Bit weird

Vehicle is a Mercedes 280SE 1975, D Jetronic

VIN - 116024 22 049694

I believe the engine is M110.983

Have you done basic things like check points (set to about 0.014"), cap properly seated, contacts clean and rotor in good shape.

Looking at your picture, you can see the green wire poking out where it exits the distributor. Make sure it is not grounding onto the distributor or the shielding wire that covers it at that point. Then check it along the way and at other end. Without that wire properly connected, the car won't run.

If you don't have manuals with wiring diagrams, this section from our V-8 should be more or less the same. Ignition system is covered in 07.5.
https://www.tonk.ca/Index/117.4index.html.

Worst situation, is that you messed up the switchgear (or coil). If switchgear, a Pertronix is the low cost solution. It would also replace the points. But you would need new coil for that too.

Ok, so thought I'd post the fix to my situation

So, I'm quite sure the ignition was left on

this caused one of the ballast resistors to fail and also the the condenser

Replaced those parts, but still wouldn't start

Started checking the switch gear unit, and thought this was the problem

However, got a spark and the engine started when the battery was on the charger

So, apart from the the resistor and the the capacitor make sure your battery is properly charged

Ok, so thought I'd post the fix to my situation

So, I'm quite sure the ignition was left on

this caused one of the ballast resistors to fail and also the the condenser

Replaced those parts, but still wouldn't start

Started checking the switch gear unit, and thought this was the problem

However, got a spark and the engine started when the battery was on the charger

So, apart from the the resistor and the the capacitor make sure your battery is properly charged

Have had a few of those cars :
with a V8 sometimes a 6 the Power steering Pump can leak and ATF Oil gets

on the D Side Fender well shorting out all that ING stuff
Pressure wash is the fix sometimes and then the oil leak