How to install your underdrive crankshaft pulley

[MetroMPG]

i do have a question though;what's a daox???

It's a secret. He won't tell me either.

Anyway, still a good write-up, Mr Doax.

[MetroMPG]

Re: loosening that 17mm bolt holding on the pulley...

This is the one tricky thing to do. Thankfully the torque specs aren't real horrible on the Aveo. You have to remove this bolt. It has a 17mm head. The easiest way to do this is with an impact wrench.

If you don't have an impact wrench (or even if you do, but it's spinning the engine):

One option is to apply the foot brake to stop the transmission (thus the engine, if it's in gear - manual tranny) from turning. That will give you some resistance to work against. You can still do this as a 1-person job if you wedge something the right length between the brake pedal and the front of the lower seat cushion. You can slide the seat forward to press down & hold the brake.

Works best if the engine has been running recently so there's vacuum assist still in the power brake system.

Not sure if this will work with an automatic. Will work with a manual transmission though. With an automatic, will the parking pin keep the engine from turning with one wheel in the air? Dunno. I've only owned one automatic and that was a long time ago.

[XJCasper]

How is the butt dyno?

Any difference?

[xintersecty]

How is the butt dyno?

Any difference?

I did my change over the weekend while doing an oil change. I think it's a little quicker on the start. I did drive 300 miles yesterday back to my new home in SC and had a drop in performance on MPG, 29.80. Usually around 32. Granted I did drive hard on my trip. My average speed was around 80 plus. So over the next week I will be doing more laid back driving between home and Greenville and I will monitor my MPG. I changed my air filter around October. How ofter should I change my air filter?

[dleebold]

i can't get that damn crank pulley bolt off!!!! used an air impack gun,but my compressor must not have enough umph!!! called my mechanic down the street and he's going to do it next monday.(decided to do this before i broke something),mechanic i am not.i'll post next week.

[xintersecty]

My pulley came off easily. I had broken the tightness when I replaced the timing belt. This is what I did to get the damn thing off originally: Since it is heavy steel, I used channel locks directly on the pulley by gripping the inside and outside to hold it still. I then was able to break the nut. I would not do this with the Alloy Underdrive pulley and the channel locks teeth would damage the belt groves.

[petrified.rabbit]

and old timers trick i learned. Go buy yourself a "rough" leather belt, in like a size 40ish.. On one end, cut a slit, or stamp a hole wrap and sew a ring on the end.. whatever. wrap it wet and tight around the pulley the full length.leaving enough off the end to stick a screwdriver or pry bar through the hole and against the pulley.. hod it tight it will create enough friction (most of the time) to either let the bolt break or slam your knuckles off something really hard.

[dleebold]

called another mechanic and he could get it in.the last post were great advice.but to be truthful,before i got really mad and broke something(knuckle,bolt,car slips off of jack stand,strip socket,torn serp-belt,thought i better leave it to someone who knows what they are doing.cost was $30.i have a scan gauge and noticed like everyone else a performance gain.i also noticed a gas mileage improvement.before the gauge would fluctuate between 26mpg and 35mpg.on the way home it was 32mpg and 47mpg.i'll have to run a few tanks of gas to see how much of a mpg gain we can expect.hopefully a bunch.crank pulley is around 5 lbs lighter so should be better on gas and a performance boost.

[xintersecty]

I just got done with an other tank of gas with easier driving than my manic 80 MPH+. I measured 32.95 miles per gallon (33 MPG). I am very pleased. Now to see if it is going to be consistent. Interesting enough I noticed a audible change in engine sound. Has anybody else noticed a change? It sounds a little more meaty. Granted I have a SVP with the add on AC. I think the arrangement is slightly different from an Aveo with factory AC.

I used a Dayco Poly Rib Belt 5060740 6PK1880. I am not sure how to read the part numbers and which of those numbers is the length. I had to move my tensioner all the way out to slide the belt on. Will the belt stretch over time? Should I get a slightly bigger belt?

[petrified.rabbit]

i believe you are running the stock size belt there xintersecty.. 740mm..