Pagoda SL Group

W113 Pagoda SL Group => Electrical and Instruments => Topic started by: MBinIllinois on July 13, 2011, 16:10:30

Title: Starter doesn't engage...
Post by: MBinIllinois on July 13, 2011, 16:10:30
Hi everyone,

I am a new member from Chicago, owning a beloved '67 250SL (57,000 miles)  :)

Unfortunately, the car developed a starting issue over the last few weeks...

Here are the symptoms:

The ignition lights come on, the fuel pump kicks in and the usual clicks occur (cold start valve I assume), but the starter doesn't engage.
I read some of the posts here addressing similar problems but the one thing that puzzles me with my issue is the fact that after the failed starting attempt, everything involved in the start up process goes dead for a while: fuel pump doesn't come one, no clicking valves, no ignition lights...
If I try again the next day the same process starts over: ignition lights on, fuel pump, clicks, no dice.
Battery is good and fully loaded; all other electrical consumers work fine.

Any thoughts?

Thanks
MBinIL
Title: Re: Starter doesn't engage...
Post by: Naj ✝︎ on July 13, 2011, 16:38:43
Loose connection/bad ground?

There is a ground wire battery to chassis and another chassis to engine (left rear at bell housing).
Wires on battery or at starter may be loose?

Naj
Title: Re: Starter doesn't engage...
Post by: Jonny B on July 13, 2011, 17:28:56
Bad grounds can be a real devil as Naj indicates.

Did you check the fuses are all making good contact? One of my annual rituals is to twist and turn them to be sure they are seating well.

Also, stretching a bit here - is this an automatic? Is the neutral safety switch adjusted/working? Not sure if that would produce the symptoms as typed,but it can prevent the car from starting.
Title: Re: Starter doesn't engage...
Post by: ja17 on July 13, 2011, 22:37:29
Hello,

Check and double check and clean the connection at the battery. Also if you have any bolt on replacement ends on the battery cables, take them apart and clean the connection at the cable.
Title: Re: Starter doesn't engage...
Post by: glenn on July 14, 2011, 00:47:02
Agree that the battery and starter connections should be cleaned-both ends of the minus(ground) battery cable(at battery and chassis), both ends of the plus cable(at battery and starter), the starter to electrical system, etc.   

  Don't think there are any fuses between the battery and the starter.  12 volts goes to the light s/w, to the ignition s/w to the starter relay(thru the neutral/park s/w on a automatic).  There are fuses in the fuel management relays, etc.

  If the resistance is in the wiring harness connections, not good........
Title: Re: Starter doesn't engage...
Post by: ejboyd5 on July 14, 2011, 11:42:05
Excellent advice already offered.  Sometimes the corrosion on electrical connections will grow gradually to a point where not enough current is passed to activate a large demand such as a starter, but still passes enough to allow normal functioning of components with lesser draws.  Clean everything, especially engine ground connection.
Title: Re: Starter doesn't engage...
Post by: MBinIllinois on July 14, 2011, 21:42:43
Thank you all!

Yep, automatic (knew I'd forget at least one important detail).
Will follow advice and double check all the connections as recommended.
Fuses are all OK and twisted  ;)

Will keep you posted...

Thanks
MBinIL
Title: Re: Starter doesn't engage...
Post by: MBinIllinois on July 15, 2011, 21:22:23
OK, it was the +/starter cable. Even though the connection at the battery looked really clean, removing and cleaning the connector and applying a little grease fixed the problem :)

Thanks everyone!
MBinIlL