Engine Knock

[captndave737]

My car has been sitting since it suddenly developed a loud knock. I drove home about 3 miles when it happened. I pulled the fan belt and ran it for a few seconds to make sure it wasn't an accessory, it wasn't. Checked the balancer and flex plate and found no problem but the crankshaft seemed to have a lot of end play.

Today I pulled the oil pan. There was some non ferrous metal particles in the oil but didn't seem like that much.

The thrust bearing is shot but everything else seems really tight. The bearing is worn almost completely gone on the back and not that much in the front. I'm assuming the back wearing faster is normal??

Here's some photos.

? Would that cause a knock? Has anyone replaced the thrust bearing from the bottom? Dropping the crank without pulling the heads?

 

[Mike T]

Yes that will knock. You can make a pin to insert in the crank oil hole that sticks out just enough to turn the bearing out. The new bearing can be turned back in the same way after you have hand feed it as far as you can.

Now the not so good news and I'm sure others will have more to add.....you really need to find what caused the problem in the first place and from the photo it looks like the thrust surface has hit the block. The thrust surface has to be perfectly smooth and if it's scored or out of spec it will fail again.

 

[DarthBuick]

I wonder if it could be torque converter related. I was burning thrust bearing in my old 502 and it was my converter ballooning. Here is what it looks like when a converter goes wrong.

 

[captndave737]

Yes that will knock. You can make a pin to insert in the crank oil hole that sticks out just enough to turn the bearing out. The new bearing can be turned back in the same way after you have hand feed it as far as you can.

Now the not so good news and I'm sure others will have more to add.....you really need to find what caused the problem in the first place and from the photo it looks like the thrust surface has hit the block. The thrust surface has to be perfectly smooth and if it's scored or out of spec it will fail again.

Thanks,

I was hoping it was just 220,000 miles of hard acceleration and half of it while towing a boat.

I'll inspect the thrust surface closely and replace the bearing if it looks ok. If not I guess the engine will be pulled for the first time.