First time posting here...I have an 83 Mitsu Mighty Max 4WD 2.3L Diesel truck. I just replaced the water pump, and had to remove the two timing belt covers to get access. While in there I noticed that the vehicle is supposed to have two timing belts, the second of which is labeled as the silent timing belt, or timing belt B. My truck has all the parts for the belt to rest on, but the belt is missing. I've had the truck for 40,000 miles and this is the first time I've openend the timing belt covers. So I'm curious, what is this belt for, and why has my truck been running fine without it? Do I need to install the belt, or will it run fine as is? Any advice would be much appreciated....

:00000732: The second belt is a balance belt and yes it is needeed. I just replaced my ones on a 4d56. They are easy to do and have all the marks on the pullys which you just match up with the marks on the front of the motor.You have to remove your bottom pully though.

So if the second belt is necessary, how is it that my truck has been running without it for at least 40,000 miles? Might the absence of the second belt have done damage to the engine?

they dont do a lot but stop your motor vibrating to much. it shouldnt have done any damage but i would put one in anyway.

Cheers