2.4L 2006 Accord Timing Chain Failure

[Market525]

I was hoping to get some opinions here ....

Looking at buying a 2006 Accord 2.4L, automatic, w/ 84K from the original owner.

She has maintained the car pretty well, backed up her claims with receipts. Looking through them, I see the timing chain was replaced @ 52,000 miles!
She told me the CEL came on and she had to have the car towed when it happened.

The repair was done by a Honda dealer -- reading the repair order, they replaced the chain, all guides, and the auto tensioner due to "chain stretch".

This really surprised me. Any Honda dealer techs out there have any comments or input on this?

Seems to me these engines usually require no timing chain maintenance at all. I've seen these engines with 200K, with the engine never opened up.

Thoughs or experiences?

 

[Donald]

A friend who teaches auto-shop at a tech high school said he has seen some timing chain failures. He thinks instead of a nice straight run (as in my 1965 289 Mustang) the timing chain has a more complex path. He did not mention specific engines.

 

[Bill in Utah]

Very RARE. But anyone making anything some units will have problems like what happened to the unit you are looking at.

The chances of it happening again are nothing to worry about.

I like the chains and continue to buy vehicles that have them (the 2011 I just bought has a chain for timing) and am not concerned at all on having issues with the engine for the life (300k+ miles) that I will own it.

Good luck on the new purchase!

Bill

 

[Bluestream]

Originally Posted By: Donald
A friend who teaches auto-shop at a tech high school said he has seen some timing chain failures. He thinks instead of a nice straight run (as in my 1965 289 Mustang) the timing chain has a more complex path. He did not mention specific engines.


The timing chain design on an OHV engine is very simple compared to and OHC engine. On OHC As long as the traction side of the chain has a straight path you should have no problems, other than chain stretch to some degree. The tensioner side will always have some defection. Ford found this out the hard way with their 4,0L SOHC engine that had plastic guides on the traction side of the chain, when the guides started to fail faster than they could put them back together.

As for the Honda, a CEL is almost always emission related. Not sure what the dealer found with the chain, but may have replaced it as preventive maintenance whether it needed to be or not. They usually know what they can get away with when dealing with customers who are not auto savvy...

 

[chubbs1]

Originally Posted By: Bluestream
As for the Honda, a CEL is almost always emission related. Not sure what the dealer found with the chain, but may have replaced it as preventive maintenance whether it needed to be or not. They usually know what they can get away with when dealing with customers who are not auto savvy...


Very true Bluestream, the dealer very well may have "got" her and did a little more work than necessary.

I just think of my aunt who won't let me get near her Ford Fusion even to do an oil change. She takes it to the dealer and the dealer only and she wonders why it costs so much. She won't listen to anyone younger than her if they are her own family, but she trusts total strangers who are constantly ripping her off (with most repairs car or not). I'll shut up about my aunt now.

 

[bepperb]

I would think it more likely the nylon guide or the tensioner was the problem, and the dealership just replaced the entire assembly.

It would be odd, at least I haven't heard of it.

 

[JHZR2]

One of the plastic guides could have been defective.

Owning cars where chains are installed and 300k truly is no big deal, I have to wonder if the "lifetime" tc is reay the best thing. As wear ("stretch") occurs, timing of other stuff starts to be offset. Mechanical injection, which is obsolete is what comes to mind most, but valve timing wrt injection and spark must be off.

In some ways I think a tc change is a good thing, though it should not be at 54k.

 

[Drew99GT]

If the chain broke on that engine, I'd think it's an interference engine and the pistons would smack the valves.

 

[JOD]

well, being that chains don't actually stretch, I'm having a tough time with this one...

If it broke, then engine would have been toast. Either the guides were worn or the tensioner wasn't working correctly. I haven't heard of any premature guide wear, and the only stories I've ever heard with the K24 tensioners are with guys with heavily-modified engines; I know there's an aftermarket upgrade for the tensioner.

In short, I wouldn't worry about it.

 

[Bluestream]

Originally Posted By: JOD
well, being that chains don't actually stretch, I'm having a tough time with this one...


ALL timing chains stretch. Even the ones from the old OHV V8's would stretch a ton!!

 

[CBR.worm]

Yeah, chains definitely stretch, and as they stretch they wear the fronts and backs of the teeth on the sprockets. If you put a new chain on w/out replacing the sprockets, the replacement will not live nearly as long as the OE chain did.

If they didn't stretch, they wouldn't need an active tensioner. You could just set the tension correctly and be set for life.

As for the Accord, I would be leary of buying that new of a car that had the timing chain replaced without knowing more about what happened. If she had to have it towed, I would wonder if there was any damage that was not repaired - like slightly bent valves, etc.

 

[Bluestream]

I suspect the CEL light came on and she pulled over not wanting to damage anything. Called a tow truck driver who was more than happy to take her money and tow the car to a dealer

 

[edhackett]

Come on Bluestream, get with the program. Timing chains don't get longer as their pins and bushings wear. Engines shrink.

Motorcycle frames get shorter too. I don't know how many times I have had to put on a shorter chain to keep one in adjustment.

Ed

 

[Bluestream]

Originally Posted By: edhackett
Come on Bluestream, get with the program. Timing chains don't get longer as their pins and bushings wear. Engines shrink.

Motorcycle frames get shorter too. I don't know how many times I have had to put on a shorter chain to keep one in adjustment.

Ed



Ed, you have obviously never worked on the shop floor and a tech...

 

[edhackett]

Quote:
If they didn't stretch, they wouldn't need an active tensioner.


I've owned several older engines that had manual tensioners. 1970's Honda motorcycles and my Alfa Romeos, for example. The Alfas had a spring loaded idler gear that was locked in place. At valve check/adjust time you would roll the exhaust cam counter clockwise, which would put the slack between the cams, you then rolled the intake cam counter clockwise to put the slack on the run with the tensioner. You then loosened the lock bolt on the tensioner to remove the slack and set the proper tension. Tighten the lock bolt and you were good to go until next tune up time.

Back on topic... the CEL could be from a cam position sensor being out of range because of the chain issue.

Ed

 

[hattaresguy]

It happens sounds like a fluke.

Mercedes was having issues for awhile with a poorly hardened cam gear that would wear, and throw the motor off time just enough to trigger a CEL.

Make enough motors and eventually something is going to go wrong, or your going to get a bad batch of parts.

 

[Bluestream]

AN active tensioner is used so that the owner does not need to keep adjusting the timing chain as they stretch. A manual tensioner may be fine for Motorcycles, but I don't think the average Mercedes owner is going to want to get their tools out and set up the timing chains every 10,000 miles, or pay someone else for the work

 

[JOD]

Originally Posted By: edhackett
Come on Bluestream, get with the program. Timing chains don't get longer as their pins and bushings wear. Engines shrink.

Motorcycle frames get shorter too. I don't know how many times I have had to put on a shorter chain to keep one in adjustment.

Ed



first off, comparing a motorcycle chain to a completely sealed engine is, in a word, ridiculous. Yes, chains "elongate" from bushing wear--but they don't "stretch". And the mechanism of elongation is important, since a timing chain operating in a completely sealed environment will see a fraction of the elongation that a motorcycle chain will see, given that it's exposed. It's not even close to being the same thing...

Generally, the tensioner in almost are cars is enough to account for the very minimal elongation the chain will see during the duty cycle of the engine, as long as the chain is seeing adequate lubrication. And overwhelmingly, if the timing system in a chain-drive engine has advanced to the point where it's causing issues, it's almost always wear from the chain guides causing the issue, not chain elongation. Chains to not "stretch", unless metals have some unique properties I don't know about...

 

[urchin]

Wow just from reading the complexities of the chain driven OHC, I'm convinced that a belt is the way to go. Especially if you are good about maintenance.

 

[Bill in Utah]

If I have a choice I'll go chain every time.

I don't need to replace the belt, prob the water pump and other parts every 90-110k miles.

Most of your mfg are getting AWAY from belts. If chains were so bad why would they go that way?

Bill