crankshaft pully

[bcjm]

71 280SL. I am in the process the replacing the front main seal. I am in my last step to remove the rankshaft pulley/vibration dampner assembly.  I removed the center hex bolt but the pully did not come off.  Do I have to remove the 6 allen bolts first? The assembly shoud be able removed as one unit by its look.  The BBB shows a puller for this job.  Can it be done by any generic gear puller?
Thanks
Bob

[Vince Canepa]

You must remove the six bolts.  They hold the pulley to the counterweight.  Sandwiched in between is the vibration damper.  The big bolt holds the counterweight on the crankshaft.  You will need a puller to get the counterweight off.

Vince Canepa
1967 250SL
113.043-10-001543
568H Signal Red
116 Caviar MB-Tex

[bcjm]

Does any three prongs gear puller do the trick?  Do I use the puller to hold the disk from outside or inside?

[ja17]

Hello Bob,


The six allen bolts will be a real challenge. They are usually locked into place with a thread locking compound. Take a blunt drift or rod and smack them with a large hammer first. Make sure that the allen sockets are clean of dirt. If  you start rounding the heads out, your in for a long evening. The pulleys and vibration dampner can be removed easily after the six bolts are out. The iron crankshaft counterweight will need to be pulled.

Use the three branch puller which uses bolts to thread into the threaded holes of the cranshaft couterweight. I will try post pictures this evening of the tools and process.


Joe Alexander
Blacklick, Ohio

[bcjm]

Thanks Joe.  Any tips will be great.

I just tried to remove the allen bolts using an L shape allen wrench.  You are right.  It is tight.  I did not mess with it too much.  I need to find a nice long shaft allen bit to do the job. I think the short allen bit will not seat into the bolt well.

Bob

[ja17]

Hello Bob,
The secret to the whole process is having a good heavy drift (punch) and a big hammer! The blow from the hammer will break the thread sealing compound loose. Even if the heads begin to round off during removal you can hit the bolts again.


Download Attachment: Tools.JPG
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Download Attachment: drift.JPG
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Find a good quality allen stud and drive it into the head of the bolt. Make sure the allen socketsare clear from dirt and grease.

Download Attachment: allen.JPG
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(I have the deep pulleys removed already so that these photos will show up better.)
When the bolts are removed, the rubber/steel vibration dampner can be removed.

Download Attachment: removal of dampner.JPG
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If you do not have a 1/2" impact gun to remove the big 27mm crankshaft bolt , you will have to use a breaker bar and figure out how to secure the engine from turning.

Download Attachment: removal of 27mm bolt.JPG
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When the bolt is removed install the puller using three metric bolts in three of the six threaded holes in the crankshaft counterbalace.

Download Attachment: puller.JPG
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Download Attachment: puller2.JPG
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Download Attachment: removing counterbalance.JPG
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Download Attachment: removal of counterbalance 2.JPG
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The round slots in the crankshaft end, for the steel indexing dowels, are actually off center so the counterweight should only be installed in one orientation!

Download Attachment: front seal.JPG
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Download Attachment: seal removal.JPG
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Joe Alexander
Blacklick, Ohio

[bcjm]

Joe, thank you for all the photos.  My engine is still in the car so I don't think I can use a big hammer with a drift.  I do have an impact gun.  The 27MM bolt is already removed.

Where is your pully?  I thougt the 6 allen bolts holds the pully in place.

[Naj ✝︎]

Hello, Joe,
I see you have three washers on the 27mm bolt.
What engine model have you got here?
I believe the three washer mod was used on the 127 engines.
naj

65 230SL
68 280SL

[hands_aus]

bcjm

I read somewhere that if you don't replace the spacer behind the seal, the new seal will leak.

Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[bcjm]

Hey Bob, am I going to see the spacer once the seal is out?  Is it easy to replace?

I got the pulley/damper/disk out of the car finally.  It is actually a 3 pieces unit in that order.  I got the allen bit socket set from Sears.  It fits perfectly.  Standard length bit works fine.  I used a 1/2" ratchet with a long extension to hold the 27mm bolt (one end stuck to the ground).  Used a 3/8" ratchet with a 6mm allen bit from the top.  It was pretty easy to break the allen bolts.  Once the 6 allen bolts were out, pulley and damper can be removed using both hands.  

I did not have a puller Joe used (shown in his photo).  I tried to use a 3 prongs puller pulling the outside of the dish but it just did not hold tight enough.  I ended up using the steering pump pulley puller I bought from Sir tools to remove the disk (this tool, M0006, works great with the power steering pump pulley).  The puller has a thick metal piece with two holes on each end.  I inserted the allen bolts I removed earlier through the holes then threaded them into the disk.   The 27MM bolt has to be removed first to take the washers out. Put the 27MM bolts back on but don't thread it all the way to the end.  Tightening each allen bolt slowly.  Make sure the allen bolts did not pass the disk and hit the engine block.

Now I am cleaning the block before taking the seal out.

[ja17]

Hello Bob,
Glad to see the bolts were not a problem. Yes the seal ring on the crankshft can also wear. If it has a deep groove worn in it, it may  allow the new seal to leak.
A very special and expensive puller is used to remove this ring. However a little ingenuity may work to remove it.
The engine in my photo had the pulleys removed for a good photo view of the bolts.

Naj, some of the later engines had the three washer arrangement also.

Joe Alexander
Blacklick, Ohio

[Raymond]

Naj,
My M-130 engine has the three washer arrangement.  The Haynes manual reminds you that they are concave "spring" washers and the one in the middle should be opposite the other two to insure clamping force.  I just put mine back on last weekend.

I had a heck of a time when I pulled the balancer because one of the woodruff keys was mushed and I destroyed it during removal.

Ray
'68 280SL 4-spd Coupe

[bcjm]

Sorry to bother you guys with this again.  Something is not right.  I have a new front crank seal and a metal spacer installed.  Everything looks good.  Then I tried to install the disk back to the crankshaft first.  There is nothing to guide me how to put the disk on to the crankshaft initially.  I can't tell if they line up correctly until the disk is almost all the way into the shaft. The two metal keys will stop the disk go all the way into the shaft if they don't line up.   I tried couple of times without success. Am I doing something wrong.  
Also the disk can be installed 180 degree off.  The timing mark on the disk will be wrong.  I toke the disk off severial times.  I might have to open the distributor to make it is installed correctly.  

[ja17]

Hello Bob,
Remove number one spark plug, put  the 27mm crankshaf bolt and washers on the crankshaft and turn the engine by hand until you can see #1 piston come to the top of it's cylinder (use flashlight). Remove the bolt and align "0" (TDC) on counterbalance and tap it on. If the counterbalance is off a bit, just take a blunt drift and tap it in the direction you want. It will rotate.  When the dowel holes are aligned tap the dowels into place.

Yes you can get it 180 degrees off but the dowels will not align exactly but you can incorrectly force them  into place.

Looks like you have the hard part done. Good job!

Joe Alexander
Blacklick, Ohio

[Benz Dr.]

Never heard this about the 3 washers before. Something tells me this isn't right about the centre one being placed oposite the other 2. I've never installed them that way - never had one come off yet either.
Maybe I'll check this out......

Dan Caron's
 SL Barn
benzbarn@ebtech.net
 slbarn.mbz.org

[bcjm]

Joe,

Where do you tap the disk using the drift?  I threaded an allen bolt back into the disk and tap it that way but the disk will not rotate.  It is pretty right.

Bob

[bcjm]

Finally, I have to use an air hammer hitting one of the surface hole side way to rotate the disk on the crankshaft.  The factory must used a better mothod when they put the engine together. The disk and the crankshaft have to line up perfectly to tap the key into the hole.