Timing belt change on 2006 Aveo LS: My new detailed write-up

[gone.g]

Glad it went well for you - must have been the GF who did all the heavy thinking
Just curious if that was the first belt change on your '04, and how many miles are on it.

lol Yup. She takes full credit.

It actually wasn't the first timing belt change. Not sure how many times it was done before, but the water pump was an AC Delco and was in pretty decent condition. The timing belt didn't really look too frayed or anything. But I guess now we have peace of mind that it will be fine. The mileage on the car at the time of change was 384,000km.

We changed the water pump, timing belt, tensioner, idler pulley and serpentine belt. We purged the coolant system as best as we could....(which was a pain in the ass).

[Aveo5_boy]

Is it just me but the pictures in the write up are not there.

[mf70]

It's not just you. I sent a PM to the original poster, and am hoping for a response. If he's moved on to one of the BMW's in the pop-up ads, perhaps someone else saved the original post WITH pix???

[mf70]

WOW! Thanks! The pictures really help!

[mf70]

Another HOW-TO link:

Timing belt

with alternate suggestion on stopping crank pulley rotation.

As of 12/20: ALL DONE! To rephrase that: A L L D O N E ! ! ! !

Time, about 4.5 hrs, with time out for lunch.

Took advice about Lisle crowfoot wrench and 5mm Allen adapter for ratchet. Glad I did.

Everything was as described. Old belt not frayed or cracked, but marked "GM DAEWOO 96858745" . Idler seemed loose.

Waterpump clamp screws were hard to find. access to upper bolts on back timing belt cover was difficult. I left the cam gears in place. Waterpump came out from behind the cover ~fairly~ easily. 3/8 extension protruded through the crowfoot
wrench and snagged and broke some interior stiffening fins on back timing belt cover

Wasn't able to get "book" torque on crank bolt. It was about 70 ft/lb + 30deg, not 45.

Engine started smoothly.

Thanks again!

[djmarch]

Done this, great write up, but my timing belt is walking off my cam sprockets when I crank the engine by hand...Any suggestions ? I've removed everything twice now and checked for cleanliness and alignment.

[avguy]

Done this, great write up, but my timing belt is walking off my cam sprockets when I crank the engine by hand...Any suggestions ? I've removed everything twice now and checked for cleanliness and alignment.

Are you using a torque wrench to tighten the 3 Allen WP bolts? If not, maybe you're not getting them tight enough. There's a side force from the tension of the belt pulling at the WP that's working against those bolts. That extra force might be throwing you off relative to how much torque to apply, especially the bottom bolt. And if the bolts aren't tight enough that might skew the WP just enough to allow the belt to walk. Only speculation here because I never had a belt walk on me, but I did use a torque wrench.

But if you're certain those bolt are tight, then keep the top timing belt cover off, have someone else start it up while you're watching the belt, and have a hand signal ready to get it shut down in a hurry if you see any movement of the belt at the sprockets.

[djmarch]

No, I'm not using a torque wrench, but I'm tightening the 5mm hex bolts really tight. So tight that I'm afraid I might snap one off...What a poor design to use only (3), 5mm bolts to hold such a torsional load. It's walking off opposite of engine. Its walking off idler, tensioner, crank, and water pump as well. Could one of the cam sprockets be bent ? They are mounted to the camshaft correctly. Wish I had a magnetic base dial indicator to check the run out on the cam sprockets. I faught this all afternoon and know if I go with it as it is, will only shorten the life of the belt....Scratching my head on this. Would the belt tension be too tight ? The indicator points are aligned with each other. Too loose and I'm afraid the belt will jump a cog.

[avguy]

I can't imagine how you could have bent a cam pulley, unless you used a pry bar on one for some reason. And the tensioner pointers being lined up should always give the correct tension. Don't like to make this suggestion after everything you've already been through, but you may need to pull everything off and compare parts, and examine the belt tooth by tooth. Then, if nothing looks wrong you could reinstall the old parts to see if it's still walking off. If not, swap them back in, one at a time. I recommend that you get an in-lb torque wrench, because too tight on those WP bolts may squash the o ring down so much it will leak. And definitely get a new o ring before doing the final installation. You have a RPITA there - hope you get it figured out soon.

[mf70]

Also check idler and tensioner for installation. Tight? Crooked / dirt under mating surfaces?