First post, long time lurker. I started on the timing belt replacement today on my 98 4runner with the 3.4L and ran into an issue. I've done a lot of shadetree work on my cars in the past but this is my first timing belt.

I used a homemade SST to break loose the crankshaft bolt which used two pins that slid into the 3/8" holes on the pulley. After cranking on it, I felt a pop and figured it was the bolt but it turned out that the doughnut looking center part of pulley broke off. If its unclear, see the pic below in which I highlighted the section that separated. It looks like it's attached to the main part of the pulley with a rubber seal.

I managed to get the pulley off using the starter bump method but I have a few questions:
1) What is that center section? The damper?
2) Is the pulley toast? The crankshaft bolt clears the inside of the doughnut thing so I don't see any way of holding the doughnut on.
2) Should have I bolted the SST to the pulley to prevent this?

Thanks in advance.

 

Yes, it is a rubber damper and, yes, the pulley is toast, AFAIK.
I doubt bolting the SST would have prevented it. Did the woodruff key in the crank break or round off?

 

Thanks for the quick reply. The woodruff key looked fine but i'll take a closer look at it tomorrow in the daylight. Guess I'll be hitting up the junkyards tomorrow...

 

This is one reason the much maligned starter-bump method of removal is actually the way to go. JMHO.

 

Yup I learned and expensive lesson doing it that way, make sure woodruff key is fine then get a new pulley and use a chain wrench for torquing it down .

 

I checked the woodruff key, no damage.

See pics below for the actual crankshaft pulley and separated damper. The damper is just held on by a rubber seal.

When I was reading up on changing the timing belt, I saw several pulley holding tools that used pins, 3/8" drill bits, etc. It's obviously a really bad idea to rely on that rubber seal to hold up to the amount of torque required for the crankshaft bolt.

The starter-bump method worked great, broke the bolt loose on the first try. For torqueing the new pulley, I'll be bolting the pulley holder on or using a chain wrench if I can find one locally.