Timing chain question

[Flaggers]

Is it possible for a timing chain on an LS3 (or any engine I guess, mine is just an LS3) to be no good/ready for replacement however the engine sounds and runs fine? I was under the impression that you can hear when your timing chain is done, however my mechanic reckons my timing chain needs replacing yet there is no sound difference in my engine.

Cheers.

 

[stick3]

only problems ls engines have is piston slap or lifters that i heard off i cannot recall any body replacing the timing chain and if there no noise (sounding like diesel )and running smoothly i wouldn t worry about it

 

[_R_J_K_]

Not really common, the V6s throw a bunch of codes and have a heap of issues (noisy being a pretty noticeable one), wouldn't expect the OHV chain on an LS to go for a fair while - on the Buick/Ecotec and 5L, they actually last the life of the engine most of the time.

He give you any reasoning or symptoms?

 

[Flaggers]

Not really common, the V6s throw a bunch of codes and have a heap of issues (noisy being a pretty noticeable one), wouldn't expect the OHV chain on an LS to go for a fair while - on the Buick/Ecotec and 5L, they actually last the life of the engine most of the time.

He give you any reasoning or symptoms?

So here is the full story.

Bought a new VF SS with an LS3 in it and 89k on the clock a week ago and had my mate look at the engine bay (I know f all about cars, still learning) and he found a couple of things, namely some small black stuff in the oil but thinks that's just carbon build up from not being serviced for a while, the radiator had nothing in it and a tiny bit of oil underneath the rocker covers. So we took it back to the dealer, they found a small hole in the 'top tank of the radiator' and they are putting a new one in. He also said the timing chain has gone and will need replacing, which he is doing free of charge as he should.

I only had it for 2 days before we took it back and it drove like a dream and made no sort of weird noises at all - mate actually said it sounded good.

What are your thoughts?

 

[losh1971]

A timing chain can be hard to diagnose by sound alone. I couldn't find anyone who could confirm my TC was buggard when it was. I self diagnosed mine on my Buick but I still took a chance when I asked to have it stripped down to find out for sure. A fair few knowledgeable people didn't agree with my diagnosis but once apart it was we could see if was stuffed.

However, in your case if the dealer is having it replaced free of charge, by all means get it done. I don't know what's involved in replacing one on an LS but if the heads are coming off by any chance, pay the extra and get the lifters replaced, because they are the most common engine issue on late V8s.

 

[_R_J_K_]

He also said the timing chain has gone and will need replacing, which he is doing free of charge as he should.

What are your thoughts?

Private dealer or Holden? As long as you're not paying for it. Should ask for the old one back so you can 'inspect' it just to see if they actually do it.

I don't know what's involved in replacing one on an LS but if the heads are coming off by any chance

Heads don't even have to come off to do the chain on an Alloytec, the LS one is pretty much exactly the same in design as a Buick one.

 

[Flaggers]

Private dealer or Holden? As long as you're not paying for it. Should ask for the old one back so you can 'inspect' it just to see if they actually do it.

Private dealer mate and that’s a good idea, will ask tomorrow.

 

[_R_J_K_]

Private dealer mate and that’s a good idea, will ask tomorrow.

Yeah, I call BS then. Doing the whole "yeah, look at all this quality service we're giving you" - just tell the customer you're replacing a whole bunch of parts, Commodores are notorious for timing chains (albeit on the V6, but we won't mention that) so we'll just tell the customer we did a really good job at no charge etc.... Maybe I'm cynical, but the timing chain and radiator are things that are pretty apparent when they become issues, just seems super random. Maybe trying to get follow on customers from recommendations or something.

I self diagnosed mine on my Buick but I still took a chance when I asked to have it stripped down to find out for sure.

What were your symptoms?

 

[Flaggers]

Yeah, I call BS then. Doing the whole "yeah, look at all this quality service we're giving you" - just tell the customer you're replacing a whole bunch of parts, Commodores are notorious for timing chains (albeit on the V6, but we won't mention that) so we'll just tell the customer we did a really good job at no charge etc.... Maybe I'm cynical, but the timing chain and radiator are things that are pretty apparent when they become issues, just seems super random. Maybe trying to get follow on customers from recommendations or something.



What were your symptoms?

Well I have a 3 month warranty so he has to fix anything that comes up anyway, but yeah you could be right. Just hoping I haven’t bought a lemon and he’s covering something up. As I said though, sounds and drives fantastically from the small time I had with it.

 

[losh1971]

What were your symptoms?

A rattle on the down rev, that disappeared with revs and was absent on idle. Bloke who I asked to tear it down sort of agreed with my untrained ear diagnosis. But he had never heard a timing chain rattle behave like mine did. Other mech's opinions were cam bearings others thought it was nothing to worry about. The noise only appeared once I fitted the Mace 1.9s. I took the rockers back out and measured the preload on each one and messed around for a few days trying to figure it out. Once the new chain and gears went in I gained a fair bit more power, as the old bus had become a little sluggish over the few months leading up to the rocker upgrade.