I have an 1983 300 D Turbo that I bought recently. It had such horrendous motor mounts that my kids and wife named it the Rattlemobile. Well, after changing the motor mounts and adding a hood pad, it doesn’t rattle anymore, but now there are more serious problems afoot.

While driving a car full of sleeping family home from grandma’s, the power steering went out, battery light came on, and the motor began to run hot. I had no choice and limped home, eyeing the temp gauge the whole time, and later discovered that the main pulley was not turning at all.

My friend, and experienced Benz wrench, declared the following:

It appears that the following is the most likely sequence of events on this failure*... motor mounts out, continued operation caused extreme vibration, crankshaft snout bolt backed out about a quarter to three eights of an inch (no locktite evidenced on the snout bolt and the vibration*also completely backed out and lost the alt pivot bolt), harmonic balancer backed*outward enough to clear the keyways, the*woodruff keys disintegrated under the increased extreme load, the balancer spun ....snout of the crank?* Questionable, I'm anxious to see what the new*woodruff keys will look like*since the recesses for them on the crank nose look ... well ... weird to me ...

Any advice on how to proceed? I have searched the old threads, but some questions remain:

Would photos of the crankshaft snout help?

Since I don’t have the old woodruff keys, which should I get? Fastlane has several, all calibrated to different angles. How can I tell which ones to get?

Anybody have any ideas on how to hold the crankshaft in place while we torque on it without the $167 tool?

I am sure more anguished questions are to come, and thank you in advance for your kind replies

RSCarey

Sure, pictures would help. I just hope there's no damage to the crankshaft or balancer. What is this $167 tool you're talking about? The crankshaft should just bolt back in with a large deep socket. While it's out, I'd change the front seal. The hard part is holding back the engine while tightening. I believe there's someplace down by the balancer that a tool can be wedged according to the maintenance manual. If unsure, I would just get the woodruff key from the dealer. It can't be that expensive. Paul central FL
300CD 1984 290,000

photos WOULD help. Pulley can be held in place by a bolt or pipe inserted through balancer slot. Don't confuse offset woodruff keys for cam sprocket with keys for balancer - the latter are cylindrical.

__________________
'82 300SD - 361K mi - "Blue"

"Good judgement comes from experience. Experience comes from bad judgement."

listen, look, .........and duck.

I 've had a crank pulley come adrift, but if the harmonic balancer wasn't installed correctly and came adrift you could be facing some bad news. Its held in place with 2 dowel pins and a large bolt into the crank snout. Good luck

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1985 Euro 240D 5 spd 140K
1979 240D 5 spd, 40K on engine rebuild
1994 Dodge/Cummins, 5 spd, 121K
1964 Allice Chalmers D15 tractor
2014 Kubota L3800 tractor
1964 VW bug

"Lifes too short to drive a boring car"

Hello RSCarey
Good to see you posting this issue.
FYI: he read all of these threads, that I forwarded to him.

Haromonic Balancer: note of caution
http://www.peachparts.com/shopforum/showthread.php?p=158104

Failed 123 Diesel Harmonic Balancers
http://www.peachparts.com/shopforum/showthread.php?p=115016

help please with loose part on front of my 300SD's engine
http://www.peachparts.com/shopforum/showthread.php?p=360310



Crankshaft pully fell off - HELP!! I may call it quits.
http://www.peachparts.com/shopforum/showthread.php?p=930060

Harmonic balancer bolt
http://www.peachparts.com/shopforum/showthread.php?p=305827

Is it possible to retap the 27MM crankshaft pulley hole where bolt fastens?
http://www.peachparts.com/shopforum/showthread.php?p=600051

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1985 300SD
1983 300D
2003 Volvo V70

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OUCH!

My friend and I pulled off the HB & pulleys only to find that the crankshaft is toast. The inside of the HB had no keyways, only a worn-out ring inside, where they used to be.

At this point I am weighing my options regarding the replacement of the crankshaft versus finding another motor. I'll post some photos later so that you can all share in my pain.

Any thoughts on proper crankshaft replacement procedure? Assuming the crank is bad, what else would indicate a trashed bottom end?

What else should I do to the bad boy one it's out, opened up, and lying on the operating table?

Anyone know of a good source for motors in the southern California area?

RSCarey

When they did the repair were the able to restore it so that the timing marks on the pulley were still accurate (pulley indexed correctly)?

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84 300D, 82 Volvo 244Gl Diesel