RB20det timing belt tightness...

[Eikon]

I recently had my water pump and timing belt replaced. I have another thread that mentions this but is focused on start-up and idling issues. But, I have a specific question about the tightness of my timing belt.

Again, I had a local mechanic that I really trust do the work for me. He primarily works on toyota, Nissan, honda, etc... So, even though he hasn't worked on RB's before, he is familier with Nissan engines. Anyhow.. the water pump is perfect, but I think the Timing belt is too tight.

I get a whining sound from it at idle. It's loud enough to hear plainly with my roof up inside the car while it's running of course. So, it's fairly pronounced. I get the feel from driving that it is so tight that it actually may affect the effort the engine is required to give... in other words, in addition to sounding bad, I think it actually hurts performance as well.

here's my question... How do I go about loosening the timing belt?

I found this awesome write-up on timing belt install for an RB25. He mentions overtightening and it's effects on the car. http://forums.skylinesdownunde...ber=1

Here are my questions... Can I loosen the timing belt myself without taking the whole timing belt off? Is there a break-in period for a timing belt? Will it loosen a bit on it's own?From the above article, what are the differences from the RB25 process to the RB20 process?

I have a short clip on my computer that has audio, if anyone wants.. I can email it to them. Don't know if it would help much.

Thanks everyone. This noob really appreciates all of your help!

[BoostFab]

you can't really over tighten timing belt, as its tensioner is spring loaded...once it's torque down correclty the timing belt will be tighten properly, given everything is installed correctly.

did you inspected the idler bearing and the tensioner bearing? sometimes those can be worn out and cause your motor not to run properly

[JonPowell]

You CAN over tighten the timing belt tensioner if you dont hold the pulley steady while tightening the nut, can happen on ANY car...let the spring provide the proper amount of tension, secure the pulley with an allen wrench, then torque the nut.

[Eikon]

So Jon, Would I be able to remove the CAS, then remove the timing belt cover, then loosen the tensioner nut that you mentioned below, then let it release to where the spring wants it to be, then secure it with the allen wrench and retighten the bolt?

Does that sound like a proper procedure? Or do I have to remove the whole timing belt and start over from scratch? If I did that, should I just get a new tensioner and spring? What is a idler pulley? They are expensive... I don't even know what they do. .

Thanks again

[JonPowell]

Pretty close, except you forgot a couple things....

Engine must start at TDC,

ALL drive belts off, waterpump pulley off, upper timing cover off, insure cams are aligned with marks on rear timing cover and crank is at TDC on lower timing cover, loosen tensioner pulley nut, hold in place with allen wrench, tightern bolt, rotate crank 2 times & make sure that the cam & crank marks STILL line up, reassemble in reverse.

[Darius]

Maybe I'm a moron, but how does the tensioner work? I pulled it off last night and didn't see where the spring's tag end stuck out or rested against. When you put it back on the bolt, does the spring's tag end stick up and to the 11 o'clock position or does it in a different direction?

Also, what is the proper tensioning technique, because I have seen a few threads including this one and am still confused by the allen wrench part of it.

What happens after you have the belt, idler, and tensioner in position at TDC? 1) Torque down idler2) <Tensioner procedure here>

[gawdzilla]

re: "how does the tensioner work?"

the tensioner is spring loaded and can pivot on an off-center axis. This allows the tensioner to "automatically" swivel/pivot to the proper tension freely.

Once the spring and tensioner have done its task, you need to tighten down the tensioner itself so it will hold position. if you don't do this, the tensioner can still pivot freely. Make sure as you're securing it, you do not move the tensioner itself. the position it needs to be in is determined by the spring, and this determines your belt tension.