I have a 85 300sd, and when I bought the car it ran great!
About 3 days later, I went out to start it, and it just "clicked"...after a few tries, it started right up. So I went and had the battery tested. But it is fine!

For 3 weeks, not a problem!...Always started right up.

Yesterday, I took my family for a ride. Stopped at a food store, and shut it off out front, 10 minutes later, tried to start it, and there it was again!

Just clicks...like the sound of a dead battery!...But after 5 minutes later, and trying 5 times or so, it fired right up, and restarted the rest of the day.

This is confusing,. because it does it so far apart, and hard to pinpoint it.

Is this the starter locking up?...I cannot figure what else would cause this....It is just a "click", like the battery would be dead, but I still have lights and horn, and good battery....Please Help!

I have had these same symptoms with my '98 E320 for the last FIVE YEARS. It happens every 20-50 times my wife tries to start the car, but it has never proven to be a real problem, after several tries the car does start. The symptom is always the same: turn the key and you get one click (sounds to me like the solenoid) but no crank. After another 1-3 tries the car will star as normal. Go figure.

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64 230sl, my daily driver
94 E500, sold
98 E320, family and dog hauler
04 C240, safe machine for teen drivers, but a poc
08 audi a4, yes we have gone to the dark side

Exactly....It is frustrating!....I wanted to take my family about 3 hours from home to the lake, but kinda nervous about it now.

I did notice one thing. I looked for corrosion, etc...and while looking, I noticed marks on the back of the starter, like someone was hitting it with something. It is real evident, that someone was smacking it with a hammer or something.

I have only had the car for three weeks now, and runs great, until it does this wierd thing on me...I am just afraid of getting stranded far from home with 4 kids....ugh!

For both of you, your starter commutator has one or more bad spots. The problem happens When the armature stops on a bad spot.

Replace or rebuild the starter and your problem will be fixed.

I will do that. Just ordered one actually, told me 48 hours.

I wanted to run it past a few of you, cause I couldn't think of anything else it could be!

thanks again!

I had the same symptoms with a Jag XJS that ended up being a bad chassis ground. It had the battery in the trunk and the battery ground strap connection to the chassis had some corrosion/rust. Once this was cleaned up I never had this problem again.

I thought that it was a sticky solenoid because tapping the back of the starter with the solenoid energized got it started. Thats how the marks on the back of your starter got there.

As far as the starter commutator having a bad spot from HarryM. I am wondering how the starter can advance past the bad spot.

Bad / sticky solenoid maybe because the starter motor does not get power untill the solenoid engages. If you pull out the starter and jumper it and it spins ( be careful ) it is more likely a poor power conection. Starters take a lot of AMPS.

For my '98 E320, the intermittent starting problem I described (every 20-30 times the starter or solenoid would just click, but would eventually start normally after 2-4 tries) persisted after replacing the starter and after replacing battery. We have just learned to tolerate the problem over these past 5 years.

As for replacing the starter, this is one of the only jobs I have given to the dealer. I had no success and no one dared come within 100yards of my garage while I was cursing the thing: it looked like an easy R&R but turns out you need to remove the engine (well, not really, but the mounts do need to be slackened) to get the thing out. I am convinced that when they built this car they started with the starter motor and built everything else around it!

Good luck,

g

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64 230sl, my daily driver
94 E500, sold
98 E320, family and dog hauler
04 C240, safe machine for teen drivers, but a poc
08 audi a4, yes we have gone to the dark side

The clicking of the solenoid has an effect similar to tapping the starter with a screwdriver handle, and moves the armature a tiny bit every time.

I had a very similar symptom for several years on a Citroen SM (Masserati engine). The problem was finally solved when I disassembled the solenoid and found the contact bar was bent slightly and thus not making good contact when the solenoid 'pulled in'. The starter would bench check perfect, then work erratically installed. I suspect a defective starter solenoid is the root cause of the erratic start. A bad commutator segment is very unlikely.

My '91 300SE eventually starts, 8 or 10 attempts, and I can hear the starter motor turning if I hold the key in "start" momentarily after the failed start. this is usually when cold but after the car is driven to town, 15-20 miles it will start 1st time til it gets cold again. Commutator or...... I have installed a new solenoid and did have the NSS bypassed, no help. What am I overlooking or don't know about??

Thanks everyone

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1991 300SE (my ride, 279,000 miles, looks almost new
1954 Cadillac (21 yo son's car, he bought when age 15)
1972 SeaBird 19 ft runabout (old but solid, slant six, Volvo sterndrive perfect condition, undergoing complete overhaul and refit)
1998 Toyota Rav4 (my sons daily driver when he is in the Continental US, PROUDLY serving in US Navy)

ground. check and clean all grounds and cables. battery to chassis, engine to chassis. and if that doesnt work sometimes it is necessary to put on a n auxiliary ground from battery to a starter bolt.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I had neutral start switch fail on my 84 and it did the same thing. I would move the shifter and it would start right up. The switch failed to a point where the car would only start in neutral and not in park.

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2009 CLS550 55,000
2004 ML350 144,000
2004 X5 95,000
2002 X5 165,000
1996 320S 155,000 (sold)
1991 190E 192,000 (sold)
1989 300SE 160,00 (sold)
1984 300D 210,000 owned since 85, (sold)
1984 300SD 160,000 (sold)