In my research on the 4.9 I've found a service note on an engine knock that originates from the front bearing. This is apparently attributed to the belt pulling up on the front of the crank and then the firing of the two front cylinders pushing the crank down within the bearing. It's apparently completely benign and just an annoyance-not directly attributable to any kind of failures. I was wondering if anyone with a 4.9 here has experienced this, or if the usual re-routing of the belt maybe makes this a non-issue.

I haven't heard of any. Maybe cause fiero owners use a different tentioner or other type of setup. Just changed a belt recently on my grampa's 92 seville. That stock tentioner really holds the belt tight.

Never heard it or heard of it. Glad you posted this....I would have had a myocardial infarction the first day, and the engine on the bench the following day. Thanks.

Hey, I'm all about preventing myocardial infarctions. LOL

quote Originally posted by Taijiguy: In my research on the 4.9 I've found a service note on an engine knock that originates from the front bearing. This is apparently attributed to the belt pulling up on the front of the crank and then the firing of the two front cylinders pushing the crank down within the bearing. It's apparently completely benign and just an annoyance-not directly attributable to any kind of failures. I was wondering if anyone with a 4.9 here has experienced this, or if the usual re-routing of the belt maybe makes this a non-issue.

the tsb related to that crank knock that you are hearing came out in late '92. subsequently, all '93 and later engines don't have it, because the correct bearing is used in them. you can either replace the bearing with the correct bearing from the tsb, or you can just deal with it. it presents no real danger to you. i have also heard of people using thicker oil to "quiet" the bearing slap, like 15w-40 or 20w-50


anyways.. it isnt really a problem