[Midnightrider1]

Hi All
I have work on a lot of motors in my life. But this has me really confused. I have a 1998 Mustang with a 3.8 motor and has 120,000
miles on it. It has a knock in the front of the motor. I took it to our little town shop they say it is #4 rod knocking. It only knocks when under a load after it has ran for about a minuet. Also if I take the belt off of it the knocking noise isn't there when I put it under a load.
Could there be a chance it is the harmonic balancer that is going out. It sure just don't make since to me why it only knocks with the belt on. I just replace the belt about a month ago when it broke.

I sure could use a little of advice on this one. I though cancer was hard to beat but this mustang seems harder. LOL

[streetstang]

take the belt off and spin all the pulleys and see if they spin free

[Midnightrider1]

I did that and all the pulleys spends free. Gonna pull the belt off now and check to see if I have any movement in my crank or harmonic balancer. Maybe my problem is there.

[Midnightrider1]

Now I have come to the conclusion That it is very well possible be #4 wrist pin. I wouldn't think it would be timing chain slap. sounds hard. Sound is upper motor no noise from the in the oil pan at all. Noise is coming from behind the water pump and I just install a new one so I know it is not that.
Looks like may be buying a rebuilt motor or having one rebuilt.