It is normal for newer (pencil-style) glow plugs to stay on for a couple minutes after engine start. This produces smoother and cleaner idle until the engine warms up. On older cars (like my 82)the alternator isn't big enough to supply all the load for those few minutes so some battery discharge occurs but it is quickly recharged in a mile or two. But it is quite possible for the glow logic to stick or fail, which would drain the battery even with a good alternator. A couple voltage checks at the battery would be in order. Like I mentioned, a free quick check at Autozone, Advanced, Pep, etc. will tell you if the alternator and battery are working right. They have a cart they wheel out to your car and it only takes 10 minutes if they aren't busy.
-----Original Message----- From: Mercedes [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Rich Thomas Sent: Friday, August 09, 2013 10:12 AM To: Mercedes Discussion List Subject: Re: [MBZ] 300SD battery/alternator problem Well now the mech tells her that he has poked around and it has confounded him. He found that the glow plug relay stays on for some period after the car starts, which he somehow thinks is causing the battery to run down. Some mention was made of a red wire coming from a box going to short, but I am not sure which red wire or box. The girl was going to find out, and take the car to the Benz shop next door. It is clear the guy is not familiar with the car, guess I can't blame him. The GPR is fairly new as are the glow plugs, so I doubt if that is the problem. And even if it does stay on awhile that would not drain the battery, unless it is stuck even with the key off, somehow. She says the light comes on, so that should be OK -- in any case I don't think that would drain the battery. I gotta get this other car sorted and get it up to her and get this one back. --R On 8/8/13 9:34 PM, Scott Ritchey wrote: > > > I don't know the year/model but these alternators have only two connections: > One or two heavy wires that go to the battery + terminal (maybe via the > starter or a junction block) and a smaller wire for the idiot light. In > some models the alternator needs a trickle of current through the idiot > light to get the alternator started. In other words, if the "charge" idiot > light doesn't come on with the key in run the alternator may not charge. So > I'd first insure that light comes on when the key is first turned to on or > glow (assuming a charged battery). > > Going that, you probably need a real mechanic unless daughter unit fancies > herself to be one. By the way, almost any FLAPS will test the alternator in > or out of the car. > > Scott > > -----Original Message----- > From: Mercedes [mailto:mercedes-boun...@okiebenz.com] On Behalf Of Rich > Thomas > Sent: Wednesday, August 07, 2013 11:50 PM > To: Mercedes Discussion List > Subject: Re: [MBZ] 300SD battery/alternator problem > > Kinda funny, there is one like 2 doors down from her new apartment. I might > send her there. > > She had this guy do the alternator a coupla weeks ago before she moved so > that is why I told her to go back there. I'm thinking that might not have > been the actual problem, maybe a bad wire or connection or short or > something. > > --R (sent from my miniPad) > > On Aug 7, 2013, at 6:53 PM, Peter Frederick <psf...@earthlink.net> wrote: > > You need for her to find a real mechanic, this isn't rocket science, but > it's obviously out of the current "mechanic's" area of expertise. > > Look for an independent Benz mechanic. > > Peter > > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > > > > _______________________________________ > http://www.okiebenz.com > > To search list archives http://www.okiebenz.com/archive/ > > To Unsubscribe or change delivery options go to: > http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com > _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com _______________________________________ http://www.okiebenz.com To search list archives http://www.okiebenz.com/archive/ To Unsubscribe or change delivery options go to: http://mail.okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
