200TDI loose pulley/harmonic damper, buggered keyway, confused on key length

[MountainD]

Digging into my alternator issue today, pulling off the belts and noticed the front pulley was loose. I thought the extra rattle sound was valve lash at first, but now I know. Zipped off the pulley/damper to find a buggered keyslot in the damper. That explains the looseness. But you can see in the pic below that the woodruff key has been banging into the pulley and has carved out a full notch:

What is particularly weird to me is the engagement length looks supremely short. I looked at the key in the crank:

Thing is, I expected the key slot in the crank to be longer and to have a wrong length key, or possibly a sheared key...or something. I can't believe that this is the entire length of engagement. Is that correct for an 11L Defender 200TDI crank? Maybe it is normal, just not sure... Either way, time to clean stuff up.

 

[RDavisinVA]

The key is moon shaped and supposed to be longer.
You'll need to remove the cover and the timing gear to install a new key.
May as well put a new timing belt on along with a new pulley.
I'll check and see if we have any crankshaft wrenches left to hold the crank pulley so the crank bolt can be torqued properly.

 

[Napalm00]

I think on 2.5 NA, 2.5 TD, and 200 TDI you have a single key like yours that only engages part of the damper. On 300 TDI and 2.8 TGV you have two key ways in line with one another on the same plane of the crank. One keys responsibility is to run the timing gear and partially engage with the damper and the front key job is to just engage with the damper.

Whatever you do when you end up putting a new damper on here use some Scotch Brite on the end of the crank then either baste it in anti-seize or grease it and grease the inside of the damper when reassembling. It is an absolute bitch to get some of these off when they are frozen on there, Even with the proper puller.

 

[MountainD]

Thanks— is 235775 the proper key? Looks to be according to my parts manual.

also, is it possible/advisable to utilize the 300 crank to get the double key way or does that entail changing a lot of other things too? I can look into that.

 

[lcdck]

The 200tdi uses two keys and keyways. The pulley damper uses only the first as described above for the 300tdi. That part number is correct.

 

[Napalm00]

You can't use a 300 crank in a 200 block without modification to the crank in the spigot bushing area

 

[MountainD]

Thanks folks. I can confirm that the key only partially engages with the crank as designed by LR. I purchased a project 200TDI so I am able to play with parts more now. However, with that said, the enlarged slot on my damper isn't indicative of the contact portion of the keyway--it was like the damper was pretty loose/working it's way out. I'll be investigating this a bit more, of course. This is the damper off my Defender, but this is a 12L block (disco) not that it would make any difference at all as the parts we are discussing are identical.

 

[Napalm00]

whatever you end up doing, when you install both the timing pulley and the damper grease the shaft and the parts IDs. I don't use antisieze here, just grease for no particular reason

 

[meatblanket]

Good advice, if you do that you can generally pull them off using just your hands.

I always add red Loc Tite to the crankshaft bolt before torqueing it. Theoretically that should reduce the chances of it backing out and allowing this kind of thing to happen.

 

[Napalm00]

Another point would be to use a blowtorch or heat gun and remove the dust shield off the back of the old damper before you toss it.

 

[MountainD]

Thanks!

 

[Tomaco1]

Another point would be to use a blowtorch or heat gun and remove the dust shield off the back of the old damper before you toss it.

Old post, but why would you do this?

 

[MountainD]

Old post, but why would you do this?

Dust shields are NLA. New pulleys don’t come with them. Combined with they are actually good at keeping some grime off the seal.

 

[MountainD]

This post was exactly why I knew you can’t replace the key without removal…I tried…. Glad you are getting yours sorted!