Uh-oh... pulley freaked out

[nfactr]

I know this has been addressed a few times and seems to be a common problem, but can't find one piece. My pulley started to wobble and wasn't sure why, thought maybe the crank was bent or front bearings were going out but in retrospect likely not the problem as the engine would have destructed. Then on a road trip the pulley loosened enough to dump the belts off. I was in the middle of nowhere with my family and put the belts on and ran it again, in the process it tightened itself up again, which is still a WTF moment. Pulled the pulley and it appears the crankshaft gear and the pulley are totally munched out. The woodruff key is mostly in the form of dust in the timing belt area, but found a small piece of it. I am wondering if the crankshaft gear can be pulled off. I would think it has to be possible or how else would you get to the front oil seal. I have pictures, but can't seem to get them to upload.

 

Thank you for your help!!

[nfactr]

 

Crank Pulley, don't think its supposed to look like that.

 

 

Crank gear, also dont think its supposed to look like that.

Edited July 16, 2010 by nfactr
bad link

[Olnick]

Yeah, looks like you're gonna need a new harmonic balancer (crankshaft pulley) and probably a new crank sprocket. Might be able to find decent ones at a pull-and-pay or salvage yard. A new woodruff key too.

 

Bigger question is what's the condition of the crankshaft snout. Is the keyway hogged out there?

 

You might try a search on here, there've been a lot of helpful posts and good discussions in the past.

 

Good luck. And hey, welcome to USMB!

[davebugs]

I had a thread on this repair last year with pics I believe.

 

Hardest part was welding the end of the crank and dressing it up with a dremel for the new key.

 

Mine needed an oil pump as well. And of course the center timing belt cover.

 

I removed the engine to do the major maintenance anyway. I would think it would be real difficult to do with the engine in the car.

[WoodsWagon]

If you do it in the car, pull the radiator out, or at least the fans. You need a new key, crank sprocket, pully, and bolt. Don't reuse any of them, as their surfaces aren't parallel and smooth anymore so they will never hold the torque again. You may be able to retighten the bolt, but it will work back loose.

 

File the snout of the crank smooth and work on getting the crank sprocket off. Prying gently off the oil pump can help, and since you're replacing the sprocket anyway it doesn't matter if you snap the reluctor teeth off in the process. Once the sprocket is off, pry/hammer/wrench the remains of the key out of the crank. Do some filing, grinding and sanding and get the new key to go back into what remains of the keyway. If it holds in pretty good, your good to go reassembling everything else. If the keyway is too hogged out to keep the key centered, you can either weld or JB weld the key into the right spot, and file down the weld untill the crank sprocket fits over it.

 

Remember, the key carries no load under normal operation, it just keeps the pullys lined up while the bolt is tightened. Once the bolt is tight, the friction between the cheek of the crank, both sides of the crank sprocket and pully, and the head of the bolt, are what transmits the power. The key is just an allignment tool, so it's not crucial it be in perfect shape.

 

Clean all the metal shavings off of the crank and cam sensors, they are magnetic, and the shavings will be attracted to them. Have enough pile up on the end of the sensor, and it will screw up the signal generated by the sensor.

[Fuzpile]

Yeh ouchers. Yours a bit more a problem than mine was. It really got into your crank a lot.The pulley/ h/b is not any further key-gored than mine (typical 90*) but I see a ridge in the bore which says the whole thing would have to be filled and remachined. Need another pulley unless you go the weld and forget route.

[Fuzpile]

Responding is hopeless for me. I get into why the sprocket needs to be removed 1st, welding the crank with a machinable rod and before it goes thru my old cp is choked with pics and no longer logged in. :-\

[nfactr]

Project got sidelined to work and waiting for parts. Does anyone know where I can get the woodruff key? Mine is mostly dust.

[Fuzpile]

The pulley key is a dealer item . Think they are about 3.80$ ea. They are very small and actually only a locater. The compression against the two clean flat surfaces (inside pulley and face of crank sprocket) are the adhesion.

[CNY_Dave]

The pulley key is a dealer item . Think they are about 3.80$ ea. They are very small and actually only a locater. The compression against the two clean flat surfaces (inside pulley and face of crank sprocket) are the adhesion.

 

Hmmm, if it needs to fit tight against the end of the crank and the face of the sprocket, but could only fit tight against one, I'd pick the sprocket.

 

Filing the nose of the crank might move it back far enough you don't get a good tight (face) fit.

 

If the face of the sprocket is munged, I'd def. get a new sprocket.

 

Dave

[Fuzpile]

The Length of the shaft hasn't changed That much. Once the sprocket is removed it may need only some weld and reslotting but I would get a new one. That restores the face there. It's almost certain he's getting another pulley. There are piles of these things if the 2.5 uses them.