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Changed my timing belt on the side of the road

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fourgsixthree33

10+ Year Contributor
1,244
45
Oct 25, 2010
Athens, Pennsylvania
So yesterday heading home from work, my timing belt failed. It didn't snap, the teeth on the belt shredded.

So I changed the timing belt on the side of the road and limped her home. I bent valves though obviously so I am putting my 1G head on. Already got the top end gasket set, I will have head bolts tomorrow, and need to figure out something with my water pipe and thermostat housing.

Anyway, what would cause the teeth of the belt to shed? Seems as if something like the oil pump sprocket stopped turning and the belt got shredded that way.

As soon as I left work, the motor stalled. It was like something forced the motor to stop spinning. I pulled over, did a visual check, couldn't see anything wrong and the car fired right back up. Then a few miles later, the belt failed.

I am hoping the belt failed on its own and a head swap will be all I have to do. Thoughts?

The bottom end was just rebuilt at the end of last year. Don't even have 10K on it yet.
 
I think I was paranoid, but when I was spinning the oil pump sprocket by hand, it seemed a little "tight". Like it seemed it should have spun free-er. You know when you check to make sure it is in the correct phase, you turn it just passed the timing mark and it will spin backwards a little on its own? Well I couldn't get it to do that.

When was the last time the belt was replaced?

When I rebuilt the motor. Actually when I put that motor in this car. Back in March.
 
I think I was paranoid, but when I was spinning the oil pump sprocket by hand, it seemed a little "tight". Like it seemed it should have spun free-er. You know when you check to make sure it is in the correct phase, you turn it just passed the timing mark and it will spin backwards a little on its own? Well I couldn't get it to do that.



When I rebuilt the motor. Actually when I put that motor in this car. Back in March.

Sounds like your talking about the balance shaft sprocket(i could be wrong tho). Did your balance belt snap off or just the timing belt chew up? If just the timing belt i would check all of you pulleys and make sure there spinning freely.
 
Sounds like your talking about the balance shaft sprocket(i could be wrong tho). Did your balance belt snap off or just the timing belt chew up? If just the timing belt i would check all of you pulleys and make sure there spinning freely.

Yes, the rear balance shaft runs off the oil pump sprocket as well. The BS belt was still intact and looked great with absolutely no signs of deterioration.
 
first thing I thought...
 

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Did the car sit for a while? I have seen timing belts that have shredded (like yours) that sat for several years without being run.

Edit never mind: Must be a bent or damaged gear or oil contamination.
 
^^^^I have never seen this before LOL.

Did the car sit for a while? I have seen timing belts that have shredded (like yours) that sat for several years without being run.

Nope. Hasn't sat. The belt may have set for a while BNIB before I used it.

Speaking of the damaged gear theory, my motor mount bracket snapped last week and the mount dug into the cam gears pretty good. I fixed it but it was pretty bad.

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Are you running an oem oil pump or topline? I have seen the toplines fail a few times and do the same thing as what has happened to yours. Also if the oil pump gear is not spinning as smooth as you like it can be a few things. Gear to caseing clearance is worn out. Also the type of balance shaft eliminator you use or if you used one at all. The pump casing must have an oem grooved stub shaft. If its the solid stub shaft it will cause wear inside of the oil pump casing cover (ask me how I know,go ahead ask me). I had an engine start to fail a few weeks ago due to this. The pump casing where the stub shaft rode was worn and grooved so bad I had to take a hammer to it to get it out of the casing. It would turn over by hand but not happily. Also another thought, the grade 10 bolt that holds the gear to the balance/stub shaft could have backed out if not properly torqued and lock tighted. I believe they want 40 ft lbs on that little guy hence why its grade 10. Other then that I cant think of anything else that would cause and oil pump to hang up on you.

Edit: I missed the post where you said about it having balance shafts, If one of the balance shaft bearings are going out that would cause the pump to not spin as freely. I cant really think of anything else. I did also see your post on the engine mount snapping. Are your cam gears damaged to the point where it would cause a belt to shred. That seems kind of coincidental.
 
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Subscribed. This is fantastic. Better hope the pistons arent damaged from the valve contact, and from you running it even with bent valves.

Sarcasm? I know we have a personal background but I hope you have moved on from that. Head is coming off tomorrow so more information on the pistons will be added here.

Are you running an oem oil pump or topline? I have seen the toplines fail a few times and do the same thing as what has happened to yours. Also if the oil pump gear is not spinning as smooth as you like it can be a few things. Gear to caseing clearance is worn out. Also the type of balance shaft eliminator you use or if you used one at all. The pump casing must have an oem grooved stub shaft. If its the solid stub shaft it will cause wear inside of the oil pump casing cover (ask me how I know,go ahead ask me). I had an engine start to fail a few weeks ago due to this. The pump casing where the stub shaft rode was worn and grooved so bad I had to take a hammer to it to get it out of the casing. It would turn over by hand but not happily. Also another thought, the grade 10 bolt that holds the gear to the balance/stub shaft could have backed out if not properly torqued and lock tighted. I believe they want 40 ft lbs on that little guy hence why its grade 10. Other then that I cant think of anything else that would cause and oil pump to hang up on you.

Edit: I missed the post where you said about it having balance shafts, If one of the balance shaft bearings are going out that would cause the pump to not spin as freely. I cant really thing of anything else. I did also see your post on the engine mount snapping. Are your cam gears damaged to the point where it would cause a belt to shred. That seems kind of coincidental.

That is some great info. Yea, still have balance shafts. I cannot tell if the oil pump sprocket was hanging up on me. How can I tell?

The cam gears "look" fine, but as you said, coincidental. The pic I posted will probably show the cam gears just as good in person. I can't visually see anything wrong with them.

Timing was spot on after the engine mount incident as well. It didn't jump time then, which surprised the hell outta me.

It definitely felt like something was hanging up. When the car stalled the first time, I did do a quick check of the timing. All timing marks lined up perfectly. So between this point in time and a few miles down the road is when the belt shredded the teeth and jumped time.

You cannot hear any valve to piston contact at idle. Only when revving. The night I limped it home, it didn't make any noise at all up until I was a couple miles from home. Once I started to hear the noise, I didn't go over 2500RPM.

Before I put the harmonic balancer on, pulleys, acc. belts, etc after I putting the new timing belt on while on the side of the road, it didn't make any noise what-so-ever. I revved it up to about 4KRPM with no noise. Then drove it for about 8 miles with no noise, then the last couple miles home the noise became present.
 
I would say whatever is causing the stress on the belt caused it to tear up. First things I would assume caused it are: Poor quality topline oil pump (they are notchy brand new from what I have seen more than 1 time), 2nd idler pulley could be on backwards and locking it up, 3rd your cam grinding you got going on.
 
I would say whatever is causing the stress on the belt caused it to tear up. First things I would assume caused it are: Poor quality topline oil pump (they are notchy brand new from what I have seen more than 1 time), 2nd idler pulley could be on backwards and locking it up, 3rd your cam grinding you got going on.

I forgot to mention that this is an OEM oil pump. Hopefully the cam gears were the culprate. But I imagine it isn't that easy. Things never go the way I want them. Also, the idler pulley was installed correctly.
 
Spun the oil pump sprocket by hand today. It feels like it is catching up. Feels more like the balance shaft rather than the oil pump. It is a little hard to turn and about every half a turn, it will kind of vibrate. Like I can feel it rubbing or something.
 
Dropped the pan and this is what I found.

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And a couple shots up of my pistons and rods.

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And up top after head removal. Absolutely no contact was made between the pistons and valves. So the head is still good.

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So, I need to delete my balance shafts. I am certain that the metal in my pan is from my balance shaft bearing. Can you guys confirm that?
 
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