Possible to push start an automatic 300D? - PeachParts Mercedes-Benz Forum

mattmacklind · #1 04-01-2009, 02:24 PM

It seems like I read this in the owners manual. Is there some way to push start a 300D with an automatic transmission? The thread about the "S" selector made me curiouos. It seemed that the manual suggested placing the transmission in "S" and then the car could somehow be started by pushing or rolling downhill. Maybe I am nuts. I would never try it, I am just curious.

NoCalMer · #2 04-01-2009, 02:54 PM

You should try it. I have read that in the manual too. I think the trick is to get going quickly enough to lock up the torque converter.

I would like to hear from someone that has done it too.

kerry · #3 04-01-2009, 02:55 PM

Yes it can be done and has been done as reported in a number of threads on this forum.

JonL · #4 04-01-2009, 03:10 PM

The MB transmissions have a rear pump which sole purpose (IIRC) is to allow the car to be push started.

compress ignite · #5 04-01-2009, 03:28 PM

Also,You will want to TOW START any Mercedes!
(That's why there's a TOW HOOK under the Right front Bumper!)

Push Starting leads to DAMAGE!!! to the Mercedes

JonL · #6 04-01-2009, 03:32 PM

Re: Rear Pump Deleted...
When I rebuilt my '87 transmission, I remember reading that the rear pump can fail and disable the car. I recall that there is a kit available to eliminate the pump. I don't remember if it is MB kit or aftermarket. I considered doing it, but I just wanted to get the thing back together and get the car on the road and didn't track down the kit. Anybody know anything more about it?

Alastair · #7 04-01-2009, 04:59 PM

Well, Ive tried this on my old W123 300D. Its a 1980 model 722.3?

Huge hill near here, around a mile long. I rolled down there attained 30mph, selected 'S' as per manual. No joy. Tried at 40 mph, again no joy at all. Car didnt even slow as if it was trying to drive engine...

So, Gave up and got a good battery, after walking back up the hill in the blinding sun--Last summer that was!.

79Mercy · #8 04-01-2009, 05:28 PM

thats because you have to put it in N and then slam it into L.

europower · #9 04-01-2009, 05:51 PM

It will start in drive or on second, have done it a few times, it is a bit scary because on some models the car will start around 35 and others you have to pull quite a while to get it to start then you look in miror and see huge cloud of black smoke and engine is up and running.

pawoSD · #10 04-01-2009, 05:55 PM

Its L not S. I have started mine easily on the short but steep hill in front of our house several times. I roll in neutral until I hit about 25-30mph, then throw it in L, and it starts right up in 2-3 seconds.

If tow starting you'd better have a powerful tow vehicle. These cars are heavy! A 300SD can't start a 300D....we've tried. It takes all the car has just to get the other car up to 30mph....then when the car-in-tow goes into L suddenly its like an anchor is being dragged....and all the speed disappears....with no start.

420SEL or higher required as the tow vehicle.

Cr from Texas · #11 04-01-2009, 07:15 PM

Quote:

Originally Posted by compress ignite

Also,You will want to TOW START any Mercedes!
(That's why there's a TOW HOOK under the Right front Bumper!)

Push Starting leads to DAMAGE!!! to the Mercedes

Learned something! I always thought that hook was to tie the car down for hauling (as in delivery from Germany).

JonL · #12 04-01-2009, 07:32 PM

Quote:

Originally Posted by Cr from Texas

Learned something! I always thought that hook was to tie the car down for hauling (as in delivery from Germany).

Me too. In fact, that hook always looked really wimpy to me... Eyeball engineering suggested the likelihood of a catastrophic failure if the tow vehicle were to take up the tow line slack with a bit too much speed.

TonyFromWestOz · #13 04-01-2009, 07:40 PM

Quote:

Originally Posted by pawoSD

Its L not S. I have started mine easily on the short but steep hill in front of our house several times. I roll in neutral until I hit about 25-30mph, then throw it in L, and it starts right up in 2-3 seconds.

If tow starting you'd better have a powerful tow vehicle. These cars are heavy! A 300SD can't start a 300D....we've tried. It takes all the car has just to get the other car up to 30mph....then when the car-in-tow goes into L suddenly its like an anchor is being dragged....and all the speed disappears....with no start.

420SEL or higher required as the tow vehicle.

I have never had an issue with using a non-turbo 300D as a tow vehicle for starting other 300Ds. I purchased a non-running 300D a year ago, got the Mrs to tow me home, and while driving along, slipped it into S and she started right up without GPs.
The Mrs didn't even notice the additional load at srating, but did comment how well her car went up the hill to our house, considering that she was towing another car. I ended up telling her that I had started the engine on the new car and was asked why I didn't stop, unhook, and drive up without the tow rope in place.
:LOL:

pawoSD · #14 04-01-2009, 08:20 PM

Well, I was trying to tow-start going up a hill, so that might have been part of the problem.

Asking a bit too much from the o'l 617.

a2t · #15 04-01-2009, 08:36 PM

Didnt work on my 87 300D. I tried all the fwd gears, didnt even slow or feel like it was turning the engine 1 bit. 35mph, maybe it needs faster? I gave up and towed it home to replace starter. Only time I missed having manual trans...