starter issues

[xcashewx]

when i try and start my 67 230sl from it sitting for a few hours the first or second time i try cranking the motor it sounds like the solinoid engages and the gear spins but it makes this heatbreaking grinding noise. but after i tap the ignition a few times then crank it again it will start up no problem. i took off the starter making sure it wasnt loose put it back on and it still happens. the teeth on the flywheel are fine and same with the starter gear. before the car was sitting idle for 9 years. any suggestions? i cant fiure out why it grinds

[scoot]

My first guess would be that the solernoid is not engaging or not fully engaging.   My second guess is low voltage.   (actually, related to the first guess).  Check the output voltage of your battery OR if you can get this to fail reliably, see if it fails while hooked up to a jumper car.

[ja17]

Good advice from scoot, I agree.

[230slhouston]

Probelm could be the solenoid failing as Joe and Scoot have commented(it is basically an electro magnet) or sticky or damaged bendix. When you take the start of and bench test it, the bendix should engage (move forward as soon as the starter starts) when you apply voltage.

My last experience with a starter with your symptoms was the bendix.

Maistran

[ja17]

Hello Maistran,

Could be,  however the bendex (starter drive) will usually spin freely or dis-engage during starting when it goes bad. Cold weather seems to agrivate the problems also.

[scoot]

Probelm could be the solenoid failing as Joe and Scoot have commented(it is basically an electro magnet) or sticky or damaged bendix. When you take the start of and bench test it, the bendix should engage (move forward as soon as the starter starts) when you apply voltage.

This is where I have been tricked in the past.  If your car voltage is too low, the bench test works fine (because you aren't using the same battery).  I had a dreadful Marelli starter in an Alfa 2600 that fooled me for ages until I figured out that my car battery was at about 11 volts and that wasn't enough to always engage the starter...  New battery fixed my starter problem on that car...

[graphic66]

First step, clean the battery posts and all connections from the battery to starter. Watch out for those junk  battery connectors that bolt to the cable. You want one piece from the battery to starter. Very important is the ground. Sometimes the engine to chassis ground strap is compromised or missing. Clean those battery posts! I mean until they shine on the battery and the battery post connector, specifically the inside where it connects to the post. You can get a blackish grey coating on the post and that will insulate. If you can grab a battery connection and move it with your hands, it is to loose. Same for the ground, remove it where it hooks to the chassis and clean it up. Here's a few examples of some tools to make the job easier, but just some scrapers and sandpaper will work.  http://www.shopping.com/xDN-building_supplies--battery_posts_and_terminal_cleaners . This may not be the problem, but it doesn't cost anything and can't hurt. If you get the starter out, put a little low temperature grease on the sliding part of the bendix. Don't use regular grease, this can get thick in cold weather and cause problems sometimes.

[xcashewx]

i dont think it is the voltage because if i give the top of it a good hit with something hard, the first time i crank it the starter fully engages

[scoot]

i dont think it is the voltage because if i give the top of it a good hit with something hard, the first time i crank it the starter fully engages

I don't think that difinitively tells you that it isn't voltage.  When you whap it you are jarring things around a bit and probably making it easier for the solenoid to engage.   If the voltage is low, the solenoid may or may not have enough umph to engage.  If you whap it first, I think you are making it a little easier for it.   I still vote for checking the voltage and seeing if the problem goes away if you increase the voltage (by jumping the car for instance with a running car).

[hands_aus]

The starter motor has brushes that could be worn.