1983 240D chain tensioner guide rail removal
 

Is it possible to remove the tensioner guide rail without removing the balancer & pulley?
I noticed a notch in the balancer, perhaps the balancer can be turned where the notch clears the rail pin, and can be removed with one of those home made (bolt washers and socket)pin puller tools.
Has anyone done this?

The pulley will need to come off. But it looks quite possible.

Without an impact puller, the 'timing cover' will have to be removed.
Stacking washers will not work without removing this cover.

But the cutout in the balancer does provide the space to pull this pin using the factory method.

83 240D tensioner rail replace without removing balencer or water pump
 

Hi folks ,
a successful 240D Day today!

Yes it can be done, I did it today (to answer my own question)
(probably a MB mechanic trade secret)

(Pressure wash engine before doing work)

buy from Lowes a 1 3/4" long #8 metric bolt or stud (or cut the hex off a bolt to make a stud)
also need a washer big enough to cover slot in balancer wheel (no need for a socket)
and an #8 metric nut

Haynes manual only explains removal of rail during an engine overhaul but not mentioning only rail removal alone.

Remove everything haynes says:
neg battery terminal,
glow plugs (to make it easier to turn crank without piston compression)
throttle linkage, cam cover, thermostat housing,
chain tensioner upper guide, tensioner (right of cam sprocket) (fan pulley and fan shroud must be removed at same time) A.C. tube bracket
tie a wire chain so that it will not fall into engine.
remove cam sprocket
If you are changing the timing chain? tie a wire on both ends
Keep tension on the wire/s

but you do not have to remove the water pump or balancer to do this.

Now here is what I can't find in Haynes "Haynes is so darn vague"

1) remove large bolt holding crank position sensor
2) remove crank position sensor
3) turn crank (27mm socket with extension required) till notch in crank is
centered over tensioner rail pin. (about in 11 o'clock position)
4) just behind the crank notch, thread 1 3/4" #8mm stud into the rail tensioner pin
5) place washer and bolt on stud covering over against crank crank notch.
6) tighten nut against crank balancer to pull out tensioner rail pin until free
(it is a little tricky inserting the pin back into the new rail)
I pushed my pin back in with a pry bar against the crank balancer.

You all can figure out the rest!

"Put Put"

Good show. I broke off the chain idler pin up on top once using a slide hammer, Thought I would save some time and not rig up bolts and washers :(

I may have to do this soon; I have some questions...

• What made you determine you needed to do this?
• What parts do you recommend that I change while I'm doing this? Obviously the rail guide, but the guide pin also? Tensioner too?

240d chain tensioner rail
 

The reason I changed the rail is that I wanted to change the timing chain, because the engine has 191,000 miles on it.(decided to change the rail while at it)

I have been reading that people have been removing the water pump, radiator, alternator, balancer & pulley just to get to the chain tensioner rail pin, when none of this is necessary.

Also been reading about people ruining their crankshafts by doing goofy things like putting a long bar on a 27mm socket then starting the engine to remove the balancer crankshaft bolt. instead of using an impact wrench.

(I re-used the same pins)
Are you doing your timing chain?
if so, (from what I have been reading here)
you should also change the tensioner
Good luck with your project.

Put Put

The OP had it listed as a #8 metric but for my OM617 was a #6. It threaded nicely, I then put a deep dish socket over the 2" long bolt, then a washer, then the nut. Tightened the nut and voila out it comes. Really pretty easy.