Great video, thanks My 85 126SD continues to have a dead battery after 1 day of driving. So far I had 2 mechanics who put in 2 new batteries and 2 alternators replaced and now on the 3rd still have erratic charging from the alternator. Each of them acts in the same way, erratic sometimes it just has no output at all. While it is charging, if the headlight is turned on the voltage will drop, and a few seconds later it has no output.
Hmm. Assuming the battery is indeed ok then I would focus on two things: other significant amp draws and the alternator. I have seen some weird stuff happening with remanufactured alternators. When the same stuff happens with more than just one battery or alternator I am getting a little skeptical that this is the root cause. I would measure the individual amp draw on each fuse or take one fuse out at a time and measure your voltage. Good luck.
My Hella regulator started flickering after only 3 years. Changed to a no name brand recently. These alternators could need a cleanup after all the buildup
Yeah, unfortunately the quality of new parts and remanufactured alternators has not been great. Most original OEM units would last 10-15 years and most newer stuff barely makes it 3 years,.
Hey ralf! my w126 (300sel) has been sitting for 1.5 yrs.. when i tried starting it, it just cranks, no start.. any tips to get it running? many thanks!
Oh boy. That can have a variety of reasons. Start from the fuel pumps. Are they both running? Check on fuel filter and the pre-filter in the fuel distributor. Crack one of the fuel line open a little bit while trying to start the engine. There should be fuel coming out. Careful: fuel is very flammable. If that checks out pull out a spark plug and connect to the electric plug and position the threaded part on the cylinder head so that the threaded part makes good contact. Don't hold it. Start the engine and see if you have a spark. Good luck.
You may have to take the alternator off the engine to have better access to the screws. Giving each screw head a good whack will typically loosen them. Use vice grips or pliers to get them going. In the worst case you may have to drill off the screw heads so you can take off the regulator. Good luck.
Your videos are amazing and cataloging these things on these old benz's here is going to do some people a great service as time goes on!
Thank you! I am glad this is helpful.
That video saved me , thank you sir I got lucky to find genuine Bosch voltage regulator and solved the issue the brushes were out of town 😂
Glad it worked! I just got another replacement shipment in from Bosch made with pride in - CHINA.
Hella is also made in China
Its always good to carry a spare voltage regulator, for these vintage MB.
It is indeed a good practice for certain.
Great video, thanks
My 85 126SD continues to have a dead battery after 1 day of driving. So far I had 2 mechanics who put in 2 new batteries and 2 alternators replaced and now on the 3rd still have erratic charging from the alternator. Each of them acts in the same way, erratic sometimes it just has no output at all. While it is charging, if the headlight is turned on the voltage will drop, and a few seconds later it has no output.
Hmm. Assuming the battery is indeed ok then I would focus on two things: other significant amp draws and the alternator. I have seen some weird stuff happening with remanufactured alternators. When the same stuff happens with more than just one battery or alternator I am getting a little skeptical that this is the root cause. I would measure the individual amp draw on each fuse or take one fuse out at a time and measure your voltage. Good luck.
Thanks Ralf!
Glad you liked it.
My Hella regulator started flickering after only 3 years. Changed to a no name brand recently. These alternators could need a cleanup after all the buildup
Yeah, unfortunately the quality of new parts and remanufactured alternators has not been great. Most original OEM units would last 10-15 years and most newer stuff barely makes it 3 years,.
Hi Ralf,
Great video! Is the malfunctioning regulator a “no name” part? Did that come with a new Bosch or remanufactured Bosch Alternator?
Peter
Yes, no brand name on it and it was a reman unit. There is a lot of junk out there, right?
@@straybenzes yes there is
@@inovahightechltd :)
Hey ralf! my w126 (300sel) has been sitting for 1.5 yrs.. when i tried starting it, it just cranks, no start.. any tips to get it running? many thanks!
Oh boy. That can have a variety of reasons. Start from the fuel pumps. Are they both running? Check on fuel filter and the pre-filter in the fuel distributor. Crack one of the fuel line open a little bit while trying to start the engine. There should be fuel coming out. Careful: fuel is very flammable. If that checks out pull out a spark plug and connect to the electric plug and position the threaded part on the cylinder head so that the threaded part makes good contact. Don't hold it. Start the engine and see if you have a spark. Good luck.
I can't get to the lower screw! I have HELLA replacement parts - But the old one is attached with flathead screws non socketed
You may have to take the alternator off the engine to have better access to the screws. Giving each screw head a good whack will typically loosen them. Use vice grips or pliers to get them going. In the worst case you may have to drill off the screw heads so you can take off the regulator. Good luck.
@@straybenzes I just can’t reach it thru the top - I have a sideways ratchet, thenother came off easily
@@Guitarwolfluke I feel your pain. Most alternators are no longer the original one and the screw head types are all over the map. Fun stuff, huh?
@@straybenzes thanks for replying - I am fighting the 560SEC!
@@Guitarwolfluke Nice car!