I just finished swapping in a high-comp frankenmotor due to the original ej22 self destructing on the freeway. Flexplate to TC bolts are torqued to spec, and the flexplate showed no signs of any cracks when swapped onto the new motor.

 

When I pulled the old motor I made sure the TC stayed with the tranny, and was not pulled out. Before installing the tc to flexplate bolts I spun the tc by finger and it was smooth.

 

Now that I have it all assembled and running the front of the tranny area is making a knocking/rattling noise when in park or neutral. The noise is RPM dependent, and shifting into any gear causes the noise to disappear. The tranny appears to shift/drive normally. This is not heatshields or any contact between a hose/coupling and the frame. Probing with a screwdriver, the noise appears to be coming from the bellhousing.

 

Any ideas?

 

 

 

Isaac

I'd check axles. I had this happen to me and it was LF axle had some play.

 

You may just be paranoid from having engine out.

 

On a lift with it in park and ideling grab the axles with your hands and see if it gets quiet or has lots of movement.

Axles were one of the first things I checked, sorry I should have said that. This is a metal on metal knock from, as near as I can tell, inside the bellhousing/flexplate/TC. I am going to run out with the cam and try to get a quick video.

 

Isaac

It may be the flexplate, they do crack sometimes for no reason that we can see. Make sure the starter drive is completley being driven back into the starter as this can cause this noise too.

 

What happens whenh you power-brake?

Power-braking results in no noise, any gear that results in movement/load causes the noise to disappear.

 

I ran out and grabbed a quick video (excuse the lighting, its dark here)

 

The camera is directly under the oil pan facing the rear of the car. You can hear the rattle quite well in park, then it goes away in gear, reappears in neutral, goes away again in gear.

 

 

 

Isaac

Double check all the motor mounts and the TC installation and engine mating. A cracked flex plate is more of a ting. I am sure it is a very unhappy torque converter.

I'd first double double check all of the flex plate bolts. Spin the engine around by hand and see if you can feel or hear any thing strange.

Did you keep the dust shield at the bottom of the bell housing? Make sure it's not bent or jammed into the transmission bellhousing incorrectly.

Was there a spacer between the flexplate and crankshaft when you removed the flex plate?