4G69 excessive noise/vibration after timing belt replacement

A

Alex_96

Active Member
Picked up my car from the mechanic earlier today and had the timing belt replaced. As I drove around for a bit I noticed there's a lot more noise and vibration coming from the engine than there was before it was replaced.

Idling is fine but as I increase in rpm it slowly gets worse. Close to 3000 rpm is when it starts getting bad.

Anyone know what's up with this?
 
Only changed the timing belt? Or was it a major service? Could be a million things, from engine mounts gone to wheel weights
 
There are two belts on 69 and the second belt is for the balance shaft. If the balance shaft belt wasn't timed up properly then there is a good chance you will get what you are experiencing. It is possible to remove the balance shafts but that maybe for another conversation. I would take the car back and get them to check all the timing of both belts.
 
Took it back to the mechanic yesterday and showed him what the problem was. Turns out the balance shaft wasn't timed up properly however, there seems to be no way of lining it up 100% as it's either slightly too far forward or too far back.

Originally the mechanic had it one tooth forward so this time he moved it one tooth back and there is a slight improvement, but it's still not great unfortunately.
 
Is it like it was before the original belt change or is there more vibration now. What was the brand of the belts fitted???
 
Did he try moving it another notch?
If there is no way of getting it spot on how come every new car manages it?
 
frosty7 said:
Is it like it was before the original belt change or is there more vibration now. What was the brand of the belts fitted???
Click to expand...

There's still more vibration than how it originally was, but there was improvement when he moved the belt back a tooth.

And I'm not sure what brand of belt he used. All I know is the new accessories belt brand he put in was a Bando.

peregrine said:
Did he try moving it another notch?
If there is no way of getting it spot on how come every new car manages it?
Click to expand...

If he didn't need to take apart and reassemble everything every time he adjusted it I'm sure he could've checked. The old belt was a tooth slightly forward as well.

What else could be a factor here? I don't want to keep taking it back to the guy unless I can narrow down the issue.

Edit: Does this engine have 2 balance shafts? If so he may not have been aware of the second one.
 
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balance shaft is out of balance!! do not rev the engine hard you will probably damage something. needs timing belt removed and re time the oil pump/balance shaft belt. they are geared 3 - 1 and needs to be in the correct orientation.
 
Wow that video actually makes a lot of sense, thanks.

I'm gonna feel horrible going back to the mechanic a third time but I will show him that video and see what he says.
 
There are two balance shafts but the oil pump shaft doesn't have a 3 to 1 ratio, inside it's just a simple shaft that is driven on maybe a 3 to 1 ratio by the belt. The video is good but I think what is happening each time he turns the shaft the oil pump finds a different spot. Have a Google of the interwebs at 4g69 balance shaft and you will see no gear reduction.
 
Taking it back to the mechanic next Tuesday so lets hope for the best. Couldn't speak to him when making the appointment unfortunately but I'll be sure to specify about the oil pump and make sure he does it right, assuming he didn't.
 
Thank you guys, I've had the same problem since I had my belts changed and couldn't figure it out.
Will be talking to my mechanic tomorrow about getting it fixed
 
Went to the mechanic today and explained the oil pump situation, which he had looked up before I got there so he was able to fix it after a couple of hours. Everything is back to normal now thank goodness.

Apparently he has worked on the same engine plenty of times before but never received any complaints about vibration despite not knowing about the 3 to 1 ratio on the oil pump shaft.
 
Glad you got it sorted! Interesting that a mechanic didn't pick up a vibration as harsh as a balance Shaft being out of time though..
 
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