Timing chain question

[TTA1401]

Is there a way, other than just taking it all apart, to tell if your timing chain is on its way out the door? A buddy of mine told me that if you put a the timing light to it and if the timing is really moving around, that is a good sign that it might be bad but he also said that it is not a sure fire way to tell. Any suggestions? The car is running awesome right now and I don't want to have to take it apart if I don't need to. But, then again I might be playing the lottery. :SHOCKED: I might as well change it. Previous owner didn't know if his previous owner changed it and it now has alot of miles.

[Just a Six??]

How many miles on it? Over 60,000 & just change it. Lotteries can be unkind!!

[TTA1401]

How many miles on it? Over 60,000 & just change it. Lotteries can be unkind!!

Over 160,000 :s:

[SuperSix]

Over 160,000 :s:

Nice.. you have 10k MORE than this gear:

150k timing gear damage (http://gnttype.org/techarea/pictureguides/timingcovers/timinggearr.html)

http://gnttype.org/techarea/pictureguides/timingcovers/timing_gear.jpg


:zahn:

[FastGN007]

My GN was running great and i was playing the lottery too!!! but then i was coming home from college and 6 hours from my house, the timing chain broke!! I had 162,000 miles on it. And the car still has the stock turbo!! The gear had 8 teeth left!! If i were you, i would replace it. It will only take a weekend.

Scott

[JayC]

Its a lot easier to just change it than it is to pull the heads to replace the valves later. At best its a 2 day job if you dont know what youre doing. If you do, it's a few hours. Suck it up and change it before it costs you a lot more time and money.

[TTA1401]

Its a lot easier to just change it than it is to pull the heads to replace the valves later. At best its a 2 day job if you dont know what youre doing. If you do, it's a few hours. Suck it up and change it before it costs you a lot more time and money.
I will change it. I just wish I knew if it was changed before. Kinda sucks if I did all that work for nothing. I guess it will have to wait until next spring when I get back from Korea to do it. :dong: :yessir:

[JayC]

You should be able to tell just looking at the front of the engine. Form-a-gasket on the block, different color gasket sticking out, bolts missing/in the wrong place. Very few people can take one of these cars apart and put it back together to the point that a trained eye can't tell.

[Razor]

See one problem is our oil pan design is such that the nut inside the pan doesnt let all the oil out. So if a small chunk breaks off the chain, it sits at the bottom of the pan. If you took and through the drain plug hole vacuumed out the oil, using a steel tube and a hand held vacuum pump(Mity Vac) you would be able to pull pretty much everything out. Now let the oil settle in the pan, when you transfer from the pan, inspect the bottom. If your chain is coming apart, there will be plastic minute chunks.

this may be another way to tell. HTH

[TTA1401]

See one problem is our oil pan design is such that the nut inside the pan doesnt let all the oil out. So if a small chunk breaks off the chain, it sits at the bottom of the pan. If you took and through the drain plug hole vacuumed out the oil, using a steel tube and a hand held vacuum pump(Mity Vac) you would be able to pull pretty much everything out. Now let the oil settle in the pan, when you transfer from the pan, inspect the bottom. If your chain is coming apart, there will be plastic minute chunks.

this may be another way to tell. HTH

Well this is on my Buick and not the TTA. But since I do have this information, I can check to see if my chain broke in the TTA an check the Buick for pieces when I drain the oil. :top: If you look from under my TTA, you can see the balancer cocked sideways. I believe the crank snapped but maybe the timing chain broke and bound up somehow. But the timing chain was changed about 5000 miles ago on the TTA so that timing chain breaking probably isn't it. I don't really know until I take the oil pan off. I am too worried about the Buick because I will be in Korea for a year so the timing chain will have to wait anyways. :fol:

[nova II]

Im a little new to the mechanical of the buick 3.8 does the cam sensor run directly off the timing chain if so this is how we did on a SBC. rotate the engine to TDC using a socket and bar,use the timing marks on the balancer now remove the cap have a freind hold the rotor as anther person slowlty turns the engine backwards till it just starts to move now turn the engine over the other way till it just starts to move again check to see what the balancer say if you have more the 10dregrees slop its time to get dirty.Like I said im not sure if the cam sensor rides the chain if it does it a great check.

[SuperSix]

If you look from under my TTA, you can see the balancer cocked sideways. I believe the crank snapped but maybe the timing chain broke and bound up somehow.

Ouch!! How else could that be caused OTHER than the crank being snapped?

Ack..

[TTA1401]

Im a little new to the mechanical of the buick 3.8 does the cam sensor run directly off the timing chain if so this is how we did on a SBC. rotate the engine to TDC using a socket and bar,use the timing marks on the balancer now remove the cap have a freind hold the rotor as anther person slowlty turns the engine backwards till it just starts to move now turn the engine over the other way till it just starts to move again check to see what the balancer say if you have more the 10dregrees slop its time to get dirty.Like I said im not sure if the cam sensor rides the chain if it does it a great check.
I am sure it does but I don't know if that would work or not. I am sure someone on here does. :albert: Sounds like it would work. :top:

[TTA1401]

Ouch!! How else could that be caused OTHER than the crank being snapped?

Ack..
I know, it really sucks. :( I know the crank is broke but wondering if the snout of the crank is just broke due to the timing chain breaking. Probably not. Just throwing out shit that is in my head! :kopfkratz

[JCotton]

I know, it really sucks. :( I know the crank is broke but wondering if the snout of the crank is just broke due to the timing chain breaking. Probably not. Just throwing out shit that is in my head! :kopfkratz


Nova/s idea of checking for play in the chain is right on, I'm from the old school and that is exactly how we do it. But the best rule of thumb is if you know it's the original chain, anytime is a good time to change it. The plastic gear has become brittle from age if not from mileage. As for the crank, I've seen several just break at the journal, for no identifiable reason.

[TTA1401]

Nova/s idea of checking for play in the chain is right on, I'm from the old school and that is exactly how we do it. But the best rule of thumb is if you know it's the original chain, anytime is a good time to change it. The plastic gear has become brittle from age if not from mileage. As for the crank, I've seen several just break at the journal, for no identifiable reason.

Looks like I will be visiting your shop for the TTA when I move to Boston in a year. :rock: I am going to do what Nova II suggested today or tomorrow.

[weeee_6]

OK then, what is the recomended replacement? I livein Michigan and have at least 2 months of winter to kill :yel:

[TTA1401]

OK then, what is the recomended replacement? I livein Michigan and have at least 2 months of winter to kill :yel:

Here is the procedure.
http://gnttype.org/techarea/engine/timingchain.html
or
http://gnttype.org/techarea/engine/tchain.html

Part #(new #) to stock GM timimg chain:12537202
The new stock one has metal gears instead of the nylon ones. Also, I have heard that people use Cloys (sp?) and Rollmaster timimg sets. I believe you can get these at your local parts store.

HTH,