1984 300dt starting tourbles, battery problems
 

I am a MB diesel veteran and am stumped... kinda.

Heres the case history:
She has gone through and ruined 4 batteries in the last 4 months. Theya re warrantied so I just bring them back to sears and get a new one free. Each time it was either really really cold for a few days in a row, or I left my headlamps on by accident (the only time i ever did it). Anyways she keeps ruining $150 batteries and leaving me stranded.She hads been starting rather tough when she does start anyways.Yesterday I had a very very tough time with it but she turned over and began to run. I had to keep the key all the wy to the right and give it a ton of gas to get her to start and kepe running. finally i stopped and she died down. She emitted a tremendous ammount of smoke and soot. So, today i went to return the battery and used a second, cheap and small battery to try to get her to turn over. She turned over a little bit but was very very far away from starting. I am in massachusetts and its winter so I began to think it is poor glow plugs that are causeing my problems. The car was originaly form the south so she may still be on her first set. However someone else told me maybee it is the alternator and or alternator regulator/relay.

any help, tips, suggestions greatly appreciated.

RE: 1984 300dt starting tourbles, battery problems
 

Update:

I am replacing the glow plugs and ave bought them. Also I am considering replacing the voltage regulators

How do I know which voltage regulator I need? Internal or externall?

RE: 1984 300dt starting tourbles, battery problems
 

What about the regulator in the Altenator?

RE: 1984 300dt starting tourbles, battery problems
 

Test the Alt to see if it's putting like 14.2 volts to the battery.

RE: 1984 300dt starting tourbles, battery problems
 

renew grounds both motor and chassis. then check with an amp meter to see if there is an open circuit consuming power. it is unlikely that one open relay would drain the large battery but it my be contributing towards your problem. i am almost certain you will need the voltage regulator bolted onto the alternator. it is easy to replace and run about 20-30 dollars.finally check all battery connections for corrosion and make certain the power line to the starter is tight. i have had two bad batterys in a row, but four is very unlikley.

RE: 1984 300dt starting tourbles, battery problems
 

I have ordered the voltageregulator on friday off ebay and am waiting for it now. Hopefully this will help. Also, how much of a pain in the butt is "renewing the grounds, both motor and chassis". I assume what you mean by this is replace the negative grounding wires which ground the battery to the chassis and to the motor? I'll let you know how it goes. thanks.

RE: 1984 300dt starting tourbles, battery problems
 

Back already! I found this post:

https://mercedesforum.com/m_59384/tm.htm

and I figure that if it is not the voltage regualtor, then the next thing to replace is going to be the belt which he replaced. Was he just talking about the drive belt. The belt coming off the end of the alternator? Also, what is the "battery bulb" which he is talking about? Might that be my problem?

thanks

RE: 1984 300dt starting tourbles, battery problems
 

well, I replaced the voltage regulator (took 3 weeks to be delivered). There have been no problems since. I still have to replace 4 of the glow plugs. thanks yall