Ones in a while (about 5 times per year) my '99 ML320 will refuse to start. When I turn the key, motor will make maybe quarter of a turn as it is starting to crank but it comes to a dead, like mechanical stop. Simular to flooded cylinder or mechanical binding between starter and flywheel gears. It will start right up in a second after it, like nothing never happened. It is bothering me and I would rather fix it even though I know that second attempt will start it no problem. Can anyone explain what is going on or had this weird act happened to him? Thank you all for any input.
Bernard

 

Starter relay?

 

It's more like not enough power from battery to turn it, RPM gauge would jump to max. and back to zero, same as on my old 280SE when my battery was dead. Surprisingly, second attempt will crank fine and car will start as nothing ever happened.

 

I have seen this on various makes and models. It usually is the starter. If you pull the starter and test it, however, it will test perfectly good. The bendex drive and solanoid will pop the gear out and the motor will whir like its on crack! What I think happens is the gear teeth are beveled on the edges so if it pops out, and isnt exact, the force of the bendex drive can pop the teeth into position. It doesnt totally fail, however, so it wont whir on you like it missed. The teeth get half in to place but not enough to drive the crank of the motor. This makes everything cease like its your engine that is seized, it is not. The next time you hit it it works because the teeth line up. Power to the starter or the power of the bendex is the issue.

 

flywheel might need to be lubricated. pretty common issue

 

Changed the battery last november (two months after the original post). It was 8 years old Duralast (autozone brand) in it. Someone kept the original 2 years old probably when they resold my truck to it's previous owner. Now I have used 3 years old oem in it.
Guess what, NEVER HAD THAT ISSUE AGAIN since the replacement (for 7 months).
I would still have that Duralast in it till this day if I wouldn't find this used OEM for $50 localy at 12.75V and 1.29 specific gravity after charge is showing good health of the battery.