Hi y'all,

I'm new to the world of mercedes diesels. I have an 82 300sd, and i just replaced the orginal engine with a used one that had less than 100k miles on it. my old one was burning oil.

So the orginal starter was installed back into the car with this "new" used engine. The car won't turn on, i go to crank it and nothing. The starter was working perfectly fine with the orginal engine, but now isnt working with this "new" used one.

the battery is fine too, it has voltage.

i could easily replace the starter with a new one, but i dont know if its the starter that is the problem, or there is something wrong with this engine that its not working with the starter.

i just dont want to buy a brand new starter, go to start it, and it still doesnt work because its the engine and not the starter.

so could there be a problem with the engine that isnt allowing the starter to work? or can it only be the starter? or maybe there is a key component that i may have not installed back correctly?

any advice would be much appreciated

thanks,
ellie30411
'82 300sd

I'd check for 12 volts at the starter when you turn the key first off. Then the ground from the engine to the body or battery.

Get a thin long wire, and run it from the positive battery to the little solenoid screw on the starter. See if the starter fires up when you touch that to it, doing that is the manual way. You can use the same concept to test it outside the car too.

There are a few other things that can go wrong, there's the neutral safety switch on the transmission, maybe you just didn't hook up the starter right, maybe the ground strap is not hooked up, etc. The only engine thing that can go wrong is the engine being seized up, easy to test that by turning it by hand.

Did you hook up the ground strap to the new engine?

__________________
1977 300d 70k--sold 08
1985 300TD 185k+
1984 307d 126k--sold 8/03
1985 409d 65k--sold 06
1984 300SD 315k--daughter's car
1979 300SD 122k--sold 2/11
1999 Fuso FG Expedition Camper
1993 GMC Sierra 6.5 TD 4x4
1982 Bluebird Wanderlodge CAT 3208--Sold 2/13

i'm sorry, but what do you mean by that. turning what by hand to test the engine?

thanks

What vehicle model was the engine pulled from?

__________________
1987 300TDT - 195,000 (Original #14 head)
1993 190E 2.3 - 105,000
1981 300D - 250,000

It is very likely you forgot to hook up the ground strap to the new engine, or the connection is loose..

This is the most common cause of the issue you describe.

The ground strap goes from the body to the transmission bell housing.

Please note:
* The battery Ground bolts directly to the body by the hood hinge.
* The engine and transmission are isolated by RUBBER.
* The starter can draw 1000 AMPS.
* The thick braided ground cable from the body to the transmission bell housing is Critical.

i believe it was pulled from either a 300d or 300sd, but wouldnt that be the same type of engine since the only difference between the d and the sd is the length and width.

thanks

The engine would be the same.