w123 starter problem>
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1983 300D
w123 starter problem>
So I have an odd issue and I'm worried that it may be the starter. Apparently MB suspends the starter in mid-air and then builds the car around it because that seems to be the only way to explain what a giant pain it is to replace it from what I've read online.
I have a 1983 300D. Uses a bit of oil but I check it regularly. I've had it for 10 years and no issues other than it tends to eat batteries so I've had to replace that every 12 to 18 months or so. With that new battery and for a while afters it starts well.
About a month ago, when it was nearly 100F outside here, I drove it on the highway, parked for about an hour and it refused to start. Heard the click of the solenoid but not even a hint of cranking. Towed it to my parents nearby and the next day came by and it started right up first try. I checked the batter before starting and it was full 12+ volts and when the engine running it was 13.5+ or so. So I don't think it was the battery.
Lately now, it seems like sometimes it starts with no issues, and sometimes it takes a second. ie, I hear the solenoid click, then a pause with nothing, slow crank, and then it cranks fine and starts. It's started every time but with that pause and slow crank I worry it's going to not start at all again.
It seems like it's correlated with heat, either driving the car for a bit or sitting out in the sun. But not sure. So I'm thinking it may be that I need to replace the starter. I've replaced tie rods, radiator, brakes etc. Do all the filters and adjust the valves gapping so I feel comfortable working on it but the starter seems like it's worth paying someone to do.
so:
I have a 1983 300D. Uses a bit of oil but I check it regularly. I've had it for 10 years and no issues other than it tends to eat batteries so I've had to replace that every 12 to 18 months or so. With that new battery and for a while afters it starts well.
About a month ago, when it was nearly 100F outside here, I drove it on the highway, parked for about an hour and it refused to start. Heard the click of the solenoid but not even a hint of cranking. Towed it to my parents nearby and the next day came by and it started right up first try. I checked the batter before starting and it was full 12+ volts and when the engine running it was 13.5+ or so. So I don't think it was the battery.
Lately now, it seems like sometimes it starts with no issues, and sometimes it takes a second. ie, I hear the solenoid click, then a pause with nothing, slow crank, and then it cranks fine and starts. It's started every time but with that pause and slow crank I worry it's going to not start at all again.
It seems like it's correlated with heat, either driving the car for a bit or sitting out in the sun. But not sure. So I'm thinking it may be that I need to replace the starter. I've replaced tie rods, radiator, brakes etc. Do all the filters and adjust the valves gapping so I feel comfortable working on it but the starter seems like it's worth paying someone to do.
so:
- Given the symptoms, does it seems like its the starter? Any way to test it while in the car?
- If not, what else could it be?
- Is the starter as hard to replace as is described online?
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Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
'83 300D... BULLETPROOF
So I have an odd issue and I'm worried that it may be the starter. Apparently MB suspends the starter in mid-air and then builds the car around it because that seems to be the only way to explain what a giant pain it is to replace it from what I've read online.
I have a 1983 300D. Uses a bit of oil but I check it regularly. I've had it for 10 years and no issues other than it tends to eat batteries so I've had to replace that every 12 to 18 months or so. With that new battery and for a while afters it starts well.
About a month ago, when it was nearly 100F outside here, I drove it on the highway, parked for about an hour and it refused to start. Heard the click of the solenoid but not even a hint of cranking. Towed it to my parents nearby and the next day came by and it started right up first try. I checked the batter before starting and it was full 12+ volts and when the engine running it was 13.5+ or so. So I don't think it was the battery.
Lately now, it seems like sometimes it starts with no issues, and sometimes it takes a second. ie, I hear the solenoid click, then a pause with nothing, slow crank, and then it cranks fine and starts. It's started every time but with that pause and slow crank I worry it's going to not start at all again.
It seems like it's correlated with heat, either driving the car for a bit or sitting out in the sun. But not sure. So I'm thinking it may be that I need to replace the starter. I've replaced tie rods, radiator, brakes etc. Do all the filters and adjust the valves gapping so I feel comfortable working on it but the starter seems like it's worth paying someone to do.
so:
I have a 1983 300D. Uses a bit of oil but I check it regularly. I've had it for 10 years and no issues other than it tends to eat batteries so I've had to replace that every 12 to 18 months or so. With that new battery and for a while afters it starts well.
About a month ago, when it was nearly 100F outside here, I drove it on the highway, parked for about an hour and it refused to start. Heard the click of the solenoid but not even a hint of cranking. Towed it to my parents nearby and the next day came by and it started right up first try. I checked the batter before starting and it was full 12+ volts and when the engine running it was 13.5+ or so. So I don't think it was the battery.
Lately now, it seems like sometimes it starts with no issues, and sometimes it takes a second. ie, I hear the solenoid click, then a pause with nothing, slow crank, and then it cranks fine and starts. It's started every time but with that pause and slow crank I worry it's going to not start at all again.
It seems like it's correlated with heat, either driving the car for a bit or sitting out in the sun. But not sure. So I'm thinking it may be that I need to replace the starter. I've replaced tie rods, radiator, brakes etc. Do all the filters and adjust the valves gapping so I feel comfortable working on it but the starter seems like it's worth paying someone to do.
so:
- Given the symptoms, does it seems like its the starter? Any way to test it while in the car?
- If not, what else could it be?
- Is the starter as hard to replace as is described online?
You can have loose or oxidized connections from battery to starter and back to Batt. with the dirty return GND strap.
Batteries should last 4 to 5 years or more... not 12 to 18Mo! Either you have drain or poor charging or even both is common.
Your Glow plugs and control deserve a tune-up.
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Joined: Jun 2025
Posts: 784
Likes: 248
From: USA
Sounds like the starter solenoid or brushes are worn, especially if it’s heat-sensitive. Classic symptom click then slow crank when hot. Test it by checking voltage drop at the starter during crank or tapping it lightly when it acts up (if it starts after, it’s the starter).
Could also be a bad ground or corroded cables check battery connections and chassis grounds first.
Starter replacement on the OM617 is a pain (tight access, have to remove intake manifold), but doable if you’re patient. If you’re not up for it, paying a pro might be worth the frustration. Heat soak makes weak starters fail intermittently likely yours.
Could also be a bad ground or corroded cables check battery connections and chassis grounds first.
Starter replacement on the OM617 is a pain (tight access, have to remove intake manifold), but doable if you’re patient. If you’re not up for it, paying a pro might be worth the frustration. Heat soak makes weak starters fail intermittently likely yours.
