Timing Chain (edited)

[Supreme Cutlass]

Searches didn't turn up anything, so here we go.

As you probably know if you've read any of my other posts/rants, my car has had a pretty rough few years, etc. etc. How durable are the timing chains? Should I go ahead and replace mine? Naturally I have no idea when it was changed last. It sure looks like a PITA to even inspect...

 

EDIT whoops 3.1L VIN T

[jeremy]

what engine??? FWIW: it is most likely going to be a timing belt, assuming you have the LQ1, and they should be changed every 60k, if you don't know the last time it was changed, I would replace it.

[slick]

It could very well be the timing chain, but checking that means removing pretty much all of your accessories off of the belt-side of the engine.

 

If this is a 3.4 DOHC, you probably mean the belt. It is only 3 bolts to take off the cover.

[GP1138]

No, it's a 3100, I read his car profile.

[1990lumina]

I'd like to know as well...

[DaveFromColorado]

the stock timing sets are crap, you're lookin' at a steel chain, running on two aluminum gears that are coated with a THICK coating of Nylon (plastic) to help keep them quiet, sometimes they'll last 200+ thousand miles, sometimes they won't make it past 80 thou - it's hard to tell how bad they are without pulling the front of the engine apart -and if you're going through that effort, you may as well change the timing set while you're in there, because you're gonna replace that timing cover gasket, and front crank seal anyway.

 

--Dave.

[Guest TurboSedan]

Searches didn't turn up anything, so here we go.

As you probably know if you've read any of my other posts/rants, my car has had a pretty rough few years, etc. etc. How durable are the timing chains? Should I go ahead and replace mine? Naturally I have no idea when it was changed last. It sure looks like a PITA to even inspect...

 

EDIT whoops 3.1L VIN T

 

mine snapped at 227,000 miles, although it ran fine until it broke (which also bent two valves ). i just replaced it about 2 months ago. once you get the timing cover off it's not hard at all. just align the gears correctly and torque things to spec. although, when i replaced mine i didn't replace the gear on the crankshaft, since i didn't have the correct puller. get yourself a new damper as well. mine had chunks broken off of it. the hardest part of the job is cleaning the old gasket material off of the timing cover and block surfaces.

[DaveFromColorado]

... you didn't replace the lower gear on your timing set?!? dude, that's borderline suicide, that's the gear that takes all the abuse!

 

--Dave.

[Guest TurboSedan]

we shall see! both gears looked perfectly fine. i believe the tensioner is what did the chain in though (in my case).

[Guest TurboSedan]

you could also say that shoving 10psi through a shortblock with 227,000 miles is borderline suicide

[DaveFromColorado]

Ahh, sometimes the chains stretch and get caught on the teeth ...

 

did you have the crappy nylon gears, or did you have the actual steel gears?

 

--Dave.

[Guest TurboSedan]

steel gears, no nylon. both the original set and the set i put on were steel with no nylon at all.

[DaveFromColorado]

Ahh, I've had more then my fair share of the nylon gears break - I kept the timing chain from my first 90-degree V6 for years after it broke (and I got a set of edlebrock heads for it, believe it or not, they made 'em for the 3.0 V-6's many years ago)

 

so yeah, as we're talkin' about here (kinda) if you do change the set, make sure you have the correct gear puller to get that lower gear off, so you can change the set as a whole rather then tryin' to make it work (no offence there Josh)

 

--Dave.

[Guest TurboSedan]

no offense at all! i definately don't recommend not changing the lower gear! but in my case, i compared the new lower gear to the original and the original looked exactly the same; it didn't look worn at all so i figured i was ok.

 

the plastic tensioner on the other hand had become very brittle, and alot of plastic chunks had broken off of it. i think some of the plastic got caught between the gear and chain causing it to break.

[DaveFromColorado]

remember, that's not plastic, that's "Nylon" (which we all know is plastic anyhow, but they get offended at GM if you call it anything but Nylon)

 

--Dave.

[Supreme Cutlass]

 

mine snapped at 227,000 miles, although it ran fine until it broke (which also bent two valves ). i just replaced it about 2 months ago.

 

so there weren't any signs at all that it was worn?

[Guest TurboSedan]

not mine. it looked fine. so did the gear on the cam for that matter but i changed that since it's just 3 bolts that hold it on.

[cizin]

At 147k, I am looking to replace my timing chain before something more serious happens. I have gone to 3 shops in my area and they all have told me that it is not needed. I have seen pictures on here and don't want that to happen to me. I am starting a new project car and need my lumina to be as dependable as possible for the next year or so. Are the shops just telling me this becasue it is not needed or do they not want to do the work. I have wanted to ask this question for a couple months now but just didn't get around to it. Also, what would I expect to pay for someone to do this. Maybe its not even worth it.

[Supreme Cutlass]

I'd kinda like to know the price, too. It looks like quite a bit of labor, but maybe it's just me....