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Crankshaft pulley removal

Help! The crankshaft drive pulley for the alternator, p. s. pump, etc. on my 1996 Subaru Legacy broke loose. I’m trying to get it off to see what’s wrong, but I can’t get the center bolt out. The bolt turns a few clicks, then freewheels and does this over and over. Feels like I’m just turning the crankshaft. Anyone have any suggestions about how to proceed?

although you may have to remove the big nut on your model car;

doesn’t the pulley have about 4 or 6 bolts around the big nut?

those are the ones you need to remove.

do you have a haynes manual? there would be the answer.

I don’t know about your particular car, but the main crankshaft pulley is typically held on by the large center bolt, and the pulley itself has a slot on it which lines up with a tab on the crankshaft. You probably need something to hold the pulley while you crank the center bolt loose with a breaker bar and socket. You could try wedging something in there so the pulley doesn’t move, but it would be better to use a chain wrench… it looks like a pair of larger vice grip pliers with a chain on one end. I bought one at Harbor Freight for less than $10 (I tried Sears, local hardware store, etc… no one else had one!)

Although, if something is truly wrong making the pulley loose its grip on the crankshaft, this might not help!

Good luck.

Thanks, but that’s a completely different design than the one I’m dealing with. BTW, the Haynes manual is completely useless in this regard. They have detailed diagrams of everything else except how the pulley mounts to the shaft and all they say is, “hold the pulley with a chain wrench,” which is useless when the pulley is broken loose.

Yep, something is truly wrong. Think there’s a way to grip the flywheel, or something, to hold the shaft while I wind out the bolt? BTW, I felt all around the pulley, front and back, and couldn’t find any keyway or slot. I bet it sheared the tab right off smooth.

check this out:

Do you mean that you can’t get the crank pulley bolt out? There is a cut-out on the top of the transmission housing, where it bolts to the engine. As you turn the engine over, a cut-out will appear in the flex plate. Put a large pry bar or such tool in there to jam the engine in place and allow you to apply enough torque to the crank snout bolt to remove it. It’s tighter than…well, it’s on there pretty tight. Spec is 76-86 ft-lbs.

i found this on a subie site. see the notch in the pulley?

If it’s a manual transmission, you can just put it in 1st or reverse and chalk the wheels to hold the engine in place.

Here’s another trick you might be able to try. If the engine turns CCW and there’s a good spot to secure the breaker bar against the frame, you can try loosening the bolt with the starter motor. You’ll want to disconnect the coil wire so the engine doesn’t start and be very very sure that the breaker bar and socket are on secure, since if it wiggles off while doing this, it will severely damage your car and possibly your person.

The Vise Grip chain wrench can work to hold the crank pulley while you break loose the bolt with a long breaker bar. When I use this method, I cut an old pulley belt and use it to cushion the chain so it doesn’t gouge the pulley groove. It also provides added grip to the chain wrench. However, it works best with a solid damper/pulley. If there is any bonded rubber in the damper/pulley, it might get damaged from the removal torque.

That said, there is probably a special service tool (possibly made by Kent-Moore) and available through OTC SPX. You can check here: Kent-Moore
The only problem is you need to know the tool part number which is usually found in the factory service manual.

Edit: This all assumes the pulley is undamaged.

this is the factory tool ##2 Remove pulley bolt. To lock crankshaft, use ST. ST 499977000 CRANKSHAFT PULLEY WRENCH
3 Remove crankshaft pulley

the reason the previous mentioned chain wrenches WON’T work is because the pulley is damaged and the outside of the hub is loose from the inside which is bolted on to the crank.

you must stop the motor from turning. see previous post. thats from the factory manual.

Yes… sounds like you might try trick listed below by “GreasyJack”. You won’t be able to find the tab/slot until you take the pulley off.

Having no experiences with Subarus I will chime in and give it a WAG. The bolt you maybe trying to take off is the crankshaft sprocket bolt. The accessory drive pulley (the one you say is spinning) may be bolted directly to the crankshaft sprocket. Maybe the bolts sheared off or came loose, if that is how its setup. Do you see any bolt holes on the side of the pulley that may line up with timing belt sprocket holes?

Use an air or electric impact wrench.

Remove one of the sparkplugs. Rotate the engine until that piston is at the bottom of the cylinder. Take some nylon rope and shove it into the cylinder through the sparkplug hole. Now rotate the engine so that the rope gets compressed in the cylinder. Now you can remove the crank bolt without the engine rotating.


Air wrench is easiest and Tester’s rope trick will work fine. If it’s a manual transaxle try chocking the wheels, set the park brake, put it in gear, and hope for the best.

Another method is use a long breakover wedged against a frame rail, floor, etc. and very very quickly bump the starter motor; and only for the smallest fraction of a second. This should pop it loose.

Once you get this apart you need to inspect very carefully (VERY carefully) the crankshaft nose, the Woodruff key, and the keyway. Many times these items get damaged when something like this happens and this often means another engine is going to be needed or the one you have will need to be totally rebuilt.
There’s no easy way out on a Subaru engine when it comes to the crankshaft.