Temporary Refusal to Start

[jaxxonia]

Hello 113 group. As always, I must start by thanking all of you that are kind enough to respond to questions and problems discussed in this forum. Over the last 6 years of ownership, the Pagoda Group has provided me with many solutions, ideas and better ways of keeping my '70 280SL automatic humming along. I couldn't have done it without you and I thank you all.

Once again it is time, if you wish, for the technically inclined to play "Stump the Mechanic". Last evening, my wife asked to go for an evening ride. I know it is hard to believe, but after 6 years, she has finally learned to enjoy my other partner, too. I turned the key to give the fuel pump the usual 7 or 8 seconds to do it's thing. I turned on the ignition, but the car would not start. The typical starter sound was absent and all electrical system immediately shut down. No dash light, no glove box light, nothing at all. I waited about 10 seconds, and electrical power returned (lights worked). I tried starting again with the same result. No starter motor sound and the loss of all electrical power. And a third time.....same situation.

Saturday morning arrived and I thoroughly checked everything that I could. All fuses are intact, all electrical connections seem solid, battery appears fine. Once again, I attempted to start. Once again, same result. My mind had visions of the AAA flatbed tow driver saying something like "What do you expect.......the car is 36 years old!.

I decided on one more attempt before I made use of my Auto Club membership. Guess what....the car started up without any drama or strange noises at all. I could swear it even sounded a bit smoother than usual. At this point, I have driven the car a number of times with its typical reliability and no starting problems at all.

So now I am trying to figure out what happened (or didn't happen). Did the starter stop on a "dead" spot? Am I about to experience the need of a new starter? Or ignition? I'm at a loss. Maybe someone has had a similar situation or can offer a Pagoda-educated guess as to what is up?

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[George Davis]

I'd suspect a bad electrical connection, probably one of the following:  battery positive, battery to starter, engine block to chassis ground (both ends), or battery ground cable (both ends).  A tight connection doesn't guarantee a good connection.  I'd recommend taking each of these connections apart, cleaning and reconnecting.

Good luck, and beautiful car!

George Davis
'69 280 SL Euro manual

[ja17]

Hello,

Yes I second George's answere.
Sounds like a bad battery connection. Take the cable ends off and clean the battery posts and the cable ends. If your car has had the cable ends replaced with the standard autoparts store replacement ends, unfasten these at the connection and clean this area also.

Joe Alexander
Blacklick, Ohio

[Tom230sl]

Great photo. Were was it taken? Looks like the top of Stunt road in SoCal!??

[Cees Klumper]

Any possibility of a loose fuse?

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[tuultyme]

Be careful with those battery quick disconnects.  I had one that would occasionally need retightening for the car to start.  Until one day while at a light it worked loose and the engine died and messed up the alternator which subsequently had to replace.  So I took off the quick disconnect.

Bruce; 268Blaugrun(green) 1970 280SL; IL

[jaxxonia]

Thanks to all for your timely, and I must say, accurate responses. George was right about a tight connection not necessarily being a solid connection. As Joe suggested, I disconnected the battery cables, cleaned and brushed the battery posts and cable connections, some redressing, and I am now back enjoying the Mulholland corridor on top of the Santa Monica mountains! Yes, there was some corrosion/grime which has now been banished. With the vibration and heat cycles our engines go thru, this will now become a bi-annual maintenence routine for me. And, Bruce, I do have a quick dis-connect on there now, but will probably lose it after hearing your story. It's not a very thorough theft deterrant anyway. Maybe the car won't disappear, but all the chrome still can.

I'll probably jinx myself for saying this, but after 6 years of ownership, I still have yet to spend $$ on an unforeseen repair. I take good care of the maintenence, but the car has been pretty near bullet-proof. Come to think of it, My SL was hit by a bullet once, but that is another story.

Thanks again to you all. Happy motoring!!

Jackson

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