fiily

Motor was set at TDC before installing belt, I verified it via bellhousing and camshaft notch. Top/Bottom balance shafts lined up perfectly at each respective notch before starting also.

I installed the balance shaft belt, lined up everything tighten the belt to 180 degree turn with fingers, started the car, let it run for 1-2 minutes, put motor at TDC again, rechecked belts and the top balance shaft is aligned with notch, bottom is off by 1.5 teeth...why??

V2Rocket

with your 24mm/15/16 socket, turn the crank slowly until the balance shafts marks are on TDC, and then look at the cam sprocket and see if it is at TDC too.

sometimes the rotation ratio between cam/BS (1:4) makes them look off if they aren't.

but if its a big error then what probably happened was the sprocket moved while being tensioned...it happens sometimes.

MAGK944

Did you take up any slack on the belt before you tensioned it? Pull all the slack so it sits above the tensioner, then tension to spec. You can move the shafts slightly off their marks to get the belt to tension first, they normally require moving only one tooth in opposite ways, tension, then move back on the marks with the crank. I've always had to do them like this to avoid the problem you have, it works well but sort of difficult to explain in words, one day I'll do a video.

fiily

Why would it move 1.5 teeth after I had everything lined up correctly, TDC, both balance shafts were dead on, then I let the car run, put engine back to TDC and bottom balance shaft is off by the said amt?

This is my method of installing the Balance Belt, is it wrong?

I run the balance belt from the top balance sprocket tight/no slack around the crank pulley, over the lower balance sprocket while still tensioned, then I have the tensioner "loose" to allow the belt on.

After locking down the tensioner to where there is no slack on the balance belt, I do my 180deg. twist, adjust the tensioner, install the idler roller to barely touch the belt at the long run/ throw a credit card under the idler roller for the .05 spec from the lower balance belt run.

fiily

Yeah, i'm a visual learner 80% of the time, usually it's show me once and I won't forget, tell me how, and I'll forget until I am shown.

A video would be beneficial to the whole community, I'd appreciate it!

Gonna give it a whirl tomorrow morning.