Turning OM617 over by hand

[deniss]

On the 300SD, do I need to remove the cooling fan and plastic shroud in order to get access to the crankshaft bolt?

I needed to do this when I was changing my ATF, in order to drain the torque converter, and after failed attempts to get a tool on the crankshaft bolt, I turned the engine via the power steering pump pulley.

Do you guys use deep sockets, what length extensions, etc? I just don't seem to have anything in my arsenal that would fit without having to remove the fan and the fan shroud.

Would appreciate some pointers on this, if at some point I will want to check my IP timing.

[kerry]

I turn with the power steering nut. No need to get to the crankshaft bolt. Some people are adamantly opposed to turning the engine with the power steering nut since they think it tightens the nut too much. The shroud loosens easily but I don't know if just loosening it will give access to the crank bolt or whether you need to pull the fan to get the shroud out. If you need to remove the fan you'll need to grind down a box end wrench to fit around the fan bolts.

[Diesel911]

I can get at mine from under the Car with a Ratchet Wrench and My Injector Socket. I have a long handled Ratchet Wrench with head that bends/swivels.

I have also used the Power Steering Nut but have needed to tighten up the Power Steering Belt to do that.

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[kerry]

One hand pushing on the belt and one turning the power steering nut works for me.

[Junkman]

I use a 1/2 inch ratchet with ~ 2" extension on the crank bolt. I forgot the socket size ~ 32 mm?

I don't remember an issue with turning the torque converter. It spins independently of the engine???

[Phil_F_NM]

If you remove your glow plugs or your injectors, you're not fighting engine compression and turning it over by hand using the method Kerry mentioned or a ratchet with a long extension (on the crank bolt head) is really easy.

Phil Forrest

[deniss]

Whats the proper size wrench for the power steering pulley nut, by the way? 24 mm? (I used a huge adjustable wrench to turn it last time).

[deniss]

Originally Posted by Junkman

I use a 1/2 inch ratchet with ~ 2" extension on the crank bolt. I forgot the socket size ~ 32 mm?

And you didn't find that the fan was really in your way?

There's not much clearance for error -- gotta have that socket and extension at JUST the perfect length, I find...

[macdoe]

1/2 '' ratchet 6" extension 27mm deep socket. It fits....does'nt seem like it should..... but it does. I used to think the shroud had to come off but it does'nt.
You have to lie on your back under the front of the car. You can put the socket and extension on the crank bolt first and then plug in the ratchet or you can connect the ratchet to the extension/socket and slide it into the balancer pulley sideways until it is almost to the bolt and then manipulate it the right way and then stab around until you seat the socket over the crankbolt. It works, just try it. We used to take the shroud and fan off to do this, until it was discovered that it does actually fit without removing all that stuff. The fan is a real pain to take off....when I found out that I had been taking the fan off all those times for no reason, it was embarrasing. Try it you will see. The drawback is that if you are adjusting valves it is way easier with a second person to spot for you.

[Phil_F_NM]

If you stick a few pieces of electrical tape in and around the edges of your 27mm socket, it will grab the crank bolt head better and you can leave it hanging there while turning the motor for a valve adjustment. Just don't forget it and start the car with it there!

Phil Forrest

[SD Blue]

Personally, I use the 1/2"dr. ratchet, 6"extension and 27mm deep socket. To advance it from one-lobe-peak of the cam to the next, it takes 4 strokes of the ratchet from driver's side to passenger. It's the FSM recommended method and the brief interval to advance the engine, sure gives your back a break from prolonged leaning over the engine. Also, the valve adjustment can be done with un-bent wrenches. It's a little more tedious but doable.

[vstech]

Originally Posted by Junkman

I use a 1/2 inch ratchet with ~ 2" extension on the crank bolt. I forgot the socket size ~ 32 mm?

I don't remember an issue with turning the torque converter. It spins independently of the engine???

... if your TC spins independently of the engine... you gots some problems...

[Mölyapina]

Some random notes:

The crank bolt is 27mm. The power steering pulley is 22mm.

[Junkman]

Originally Posted by vstech

... if your TC spins independently of the engine... you gots some problems...

I don't remember the deal but had absolutely no trouble getting to the drain plug. It was soooooo easy I almost didn't believe it.
Car runs fine and I'm GLAD I don't have a problem.