I am about to get my timing belt and balance sheft belt replaced by my a coworker. I went and showed him my 98 accord i-4, and he said I still needed to get a timing belt tensioner and an idler pulley. The timing belt tensioner was easy for me to purchase online, but the idler pulley was still unwilling to be located on the internet. I went to my local Honda dealership and purchased an idler pulley, although they said some people called them other names. Anyways I went onto an Accord parts site and I noticed a part on their site called a balance shaft tensioner, and it looked very familiar to my idler pulley I purchased at the dealership except half the price. My question is are these the same parts? I have no knowledge of what an idler pulley is, and is it the same thing as a balance shaft tensioner?

 

It is probably the same thing. I would be cautious about getting non-Honda parts for a job like timing belt change though. Honda parts cost more, but they are better quality.

 

Timming belt tensioner and the balance shaft tensioner looks the same but a little difference. The Balance shaft has a key groove on one side. Look like a D shape.
IF only I should take some pix when I changed out mine last week.

 

When speaking of drive belts; timing and or serpentine (Accessory drive), idler pulleys and tensioners are very similar.
Simple one first:
Idler Pulley: Incorporates a mounting bracket to which a shaft and bearing supported wheel (pulley) is mounted in a fixed position. They are normally located between two drive pulleys repositioning the belt in such a way as to increase contact area on those pulleys.
Tensioner: Incorporates a mounting bracket, a spring loaded arm to which a shaft and bearing supported wheel (pulley) is mounted. It keeps a constant predetermined tension on the belt.

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