Easiest way to replace ring gear (1971 MB 250 w114)
 

Hi everyone,


Any ideas on easiest way to replace ring gear on 1971 MB 250 w114 (has anyone done this)?


Do you have to remove entire engine to get to it (believe it's located between transmission and engine)?


Thanks in advance,


Jub

1) Remove transmission.
2) Mark location of flywheel to crankshaft. The location may have been marked at factory; do not assume that it has been.
3) Remove flywheel (and flex plate if automatic) from crankshaft.
4) Have ring gear replaced on flywheel.
5) Reinstall flywheel/flex plate on crankshaft; reinstall transmission.

Thanks Frank!!!


I thought only way to get transmission out was to take engine and transmission out together, and then separate. But maybe I am thinking in reverse (ie, easiest way to get engine out is to take both out together).


Have a great weekend,


Jub

bench pressing a transmission is doable. To remove the transmission, you need to
1. Disconnect the battery first!
2. Drop the exhaust
3. Unbolt the cooler lines and the filler tube. catch the oil. The top end of the filler tube is bolted to the intake manifold and carries a vaccuum line down to the trans. Unbolt that too.
4. There's a lever on the throttle linkage that goes back to the transmission. disconnect that from one end or the other or both. Whatever's easy for you. This is a good time to remove the electrical connections, shift linkage and the speedo cable too.
5. Undo the drive shaft bolts and push the end aside.
6. Undo the 3(?) pairs of bolts from the engine side that hold the flywheel to the torque converter.
7. Undo the starter. There is a trick to the top bolt. It's invariably a 10mm allen key in a swivel socke that needs to be on the longest extension you can image. You can see the bolt clearly with your head by the tail end of the transmission. When you take off the bottom bolt, just move the starter forward. Don't disconnect the wires. (and you did disconnect the battery first, right?)
8. Undo the other bolts holding the transmission to the engine.
9. If you can handle a 100lb transmission do so. I find it easier to hold the transmission up with a small plank on my car jack.

Careful with removing the torque converter and putting it back in. The book says to hold the transmission pointing up so that the weight of the converter doesn't contribute to damaging the front seal.

On reassembly, replace the plastic bushing on the shift linkage, the little metal donuts for the exhaust seal to the manifold, the transmission's front shaft seal. Replace the rubber donut on the transmission/drive shaft if it looks dodgy. If you don't loose the metal crush seals, they can be reused. If the transmission filter wasn't changed recently, you might want to do that too.

-CTH