Hey folks. First time posting here. I've got a 2002 Supercrew 4x4 with the 4.6 Windsor and about 190,000 miles on it. A few months ago I bolted on a Summit underdrive pulley set and was pretty happy with the increase in pick up. However, I started hearing a slight knock within a few days that would would increase with rpm's. Over the next few weeks the noise got increasingly louder. A buddy with a stethoscope pinpointed the noise as coming from the area around the crankshaft pulley. Right now the noise is getting louder and has me pretty worried. After looking through some other threads, it seems like I could have a timing chain issue. Does this sound like the problem? And, has anybody else had this problem after installing the underdrive pulley kit? Thanks for any help.

 

Perhaps you over/under tightened the Crank pulley? When I did mine in the fall I messed up and put the incorrect spacer on the alt pulley. I realized it as soon as I started it up, so it wasn't an issue. I've put underdrive pulleys on every Ford V8 I've owned in the last 18 years and never had something happen to the timing chain as a result (4 of the vehicles were 4.6Ls with timing chains).

It sucks, but I would take the crank pulley back off and check that nothing is cross threaded. Put the stock one back on and drive it for a day-see if the noise comes back. If it doesn't then there is something wrong with the crank pulley. If it does then you'll need to look deeper and see what's what.

Timing chains on these mod motors are pretty bomber; I know of at least a half dozen mod motor equipped fords with much more mileage on them than yours and none of them ever needed a new timing chain. Hell, my '95 Bird had 225K miles on it when it was hit and it ran like a top, and my cousin just sold his '98 Mark VIII with 320K miles on it. Never had to replace the timing chain. Not to say it couldn't happen, but I bet the noise is coming from one of the new pulleys. Good luck.