Timing Chain Tensioner Failure

[g8_795]

I am currently replacing my cam and getting rid of DOD and discovered that my timing chain tensioner has failed. A big chunk of the plastic was in the front left (looking from front of car) lifter tray!!! I don't know how it got in there. Luckily this is getting replaced with the non-DOD kit from Livernois.

I just wanted everyone to know about this failure. Has anybody seen this before?

I will take pics later today once I am done wrenching on the car.
-Robert

[GRRRR8]

Mike @ New Eras was broke also when he pulled it apart.

[99-LS1-SS]

That is scary. What do you think causes that Charlie?

[Andy@Livernois]

this combined with some cam bearing wear happens from time to time on some of these cars. Right now it looks like it might be related to having a higher rev limiter from our initial inspection, but there is not enough Data around to be certain that it is linked to this. any pics of it?

[g8_795]

this combined with some cam bearing wear happens from time to time on some of these cars. Right now it looks like it might be related to having a higher rev limiter from our initial inspection, but there is not enough Data around to be certain that it is linked to this. any pics of it?

I have a pic of the piece that broke off. I am in the processing of dropping the oil pan to remove the oil pump. I will take a better pic of it before I remove it from the block.

[GRRRR8]

The factory tensioner is shit is bottom line. Once you switch to the "black" LS2 tensioner this wont happen.

[Blackdevil77]

The factory tensioner is shit is bottom line. Once you switch to the "black" LS2 tensioner this wont happen.

Is that a part of Livernois's cam package?

[Andy@Livernois]

why yes it is :D

[Blackdevil77]

why yes it is :D

:) Good! Cuz im gettin that shit this summer :D CAN'T WAIT!

[99-LS1-SS]

Is the LS3 tensioner shitty?

[Andy@Livernois]

Is the LS3 tensioner shitty?

all of the LS3's we have pulled apart had the good tensioner... but gm has been known to change stuff like that mid cycle too...

[Mike@NewEra]

I have seen this twice now, the alignment pin falls out, or was never there?

[g8_795]

Here are a few pics. The plastic piece on the bench was in my lifter tray.

How can that even happen?????

[g8_795]

Should I completely drop the oil pan and look for these parts that are missing?

Bummer. Glad I pulled the engine apart now. Now the wife agrees with me ;-)

[RacerxG8]

Are there any symptoms/odd noises that would indicate a broken tensioner?

[Andy@Livernois]

we have never noticed any odd noises on any of the cars that had that failure... as far as dropping the pan... I would if it were my car personally...

[PantherGTBlack]

... as far as dropping the pan... I would if it were my car personally...

Just an FYI, this doesn't sound too good on your shop's rep., not hating just wanted to let you know.

[Andy@Livernois]

Just an FYI, this doesn't sound too good on your shop's rep., not hating just wanted to let you know.

huh? did I miss something? he is installing the parts himself, he was asking for advice if he should drop the pan. Of course we would do this if it was the shop, i am adding that i would also drop the pan if i were installing it in my own garage if it were my own car...

[PantherGTBlack]

Of course we would do this if it was the shop, i am adding that i would also drop the pan if i were installing it in my own garage if it were my own car...

Oh I gotcha, when I read the post of yours it just sounded like you would do it, but if it was a customer's car it would be something you wouldn't be worried about. When I read it aloud, it caught my attention and I didn't want somebody else to read it and take it the wrong way. I'm planning on a non-DOD kit from you guys in the future and possibly have your shop do it since you're about 2.5 hrs away from me, so it just caught my eye. No harm intended, Andy.

[Andy@Livernois]

no prob, it just had me scratching my head...

[jbradsh1]

Oh I gotcha, when I read the post of yours it just sounded like you would do it, but if it was a customer's car it would be something you wouldn't be worried about. When I read it aloud, it caught my attention and I didn't want somebody else to read it and take it the wrong way. I'm planning on a non-DOD kit from you guys in the future and possibly have your shop do it since you're about 2.5 hrs away from me, so it just caught my eye. No harm intended, Andy.

I noticed your post as I'm heading up to Livernois for a stage 1 cam and some head work next week. I'm trying to decide on tires and wheels to upgrade to. How do you like your set-up? I'd be very interested to know the tire you picked out and your wheels and how you like the way they perform. Any details on this subject would be very much appreciated.

[Featherburner]

no prob, it just had me scratching my head...That's just the dandruff. :D

[EcoBrick Bob]

Andy,

Is the DOD valve train an issue with MagnaCharger?

If so, what does one do to get the M.C. warranty?
Have had similar issues with 502 valve train/cam/heads on our boat. Know they aren't remotely related to this... but when things break.... $$$$ into hole in water. Had a lifter break in half one time. Ruined cam... LUCKY!

[Andy@Livernois]

well, not really per se... like I said, the real reason behind the failures hasn't been ironed out, but we haven't seen a failure on a G8 with a stock RPM limiter... the Magnacharger warranty is usually up to X amount of dollars, I know we are usually good with any mod we perform...

[g8_795]

For the record. I was running mine up to 6300 or so.

[Mike@NewEra]

Also, for the record, I didn't know anything was wrong with my G8 when I took it apart and found the cam tensioner in pieces (no symptoms), and at the time I was using the stock rev limiter at the time.

[Andy@Livernois]

Also, for the record, I didn't know anything was wrong with my G8 when I took it apart and found the cam tensioner in pieces (no symptoms), and at the time I was using the stock rev limiter at the time.

hmm, well that theory is pretty much out the window then... We were thinking the higher rpm was just too much for that crappy tensioner...

[EcoBrick Bob]

hmm, well that theory is pretty much out the window then... We were thinking the higher rpm was just too much for that crappy tensioner...

Is the DOD valve train problems you have alluded to in the past few weeks just this plastic tensioner, or is there other premature wear that you were thinking was due to tunes with 200 rpm or higher rev limit?

Where I am going is.... would one be better off modding heads to remove DOD and installing a hi-lift cam etc., or a MagnaCharger and keeping stock heads and cam that will yield similar performance gains?

FYI: Talked with mechanic that fixed my 08's oil leak by replacing pan gasket. He claimed he checked rear sea when pan was off and it was tight and had no leak. He too was surprised it was the pan gasket and not the rear seal. Hope he's right....

[edmanet]

I noticed your post as I'm heading up to Livernois for a stage 1 cam and some head work next week. I'm trying to decide on tires and wheels to upgrade to. How do you like your set-up? I'd be very interested to know the tire you picked out and your wheels and how you like the way they perform. Any details on this subject would be very much appreciated.


Since I'm using stock 18" rims Andy suggested that I try the Nitto Invo
245/45ZR/18 tire. It has the same diameter as the stock tire plus its supposed to be a lot stickier. I bought a set but haven't put them on the car to try out.

[g8_795]

Is the DOD valve train problems you have alluded to in the past few weeks just this plastic tensioner, or is there other premature wear that you were thinking was due to tunes with 200 rpm or higher rev limit?

Where I am going is.... would one be better off modding heads to remove DOD and installing a hi-lift cam etc., or a MagnaCharger and keeping stock heads and cam that will yield similar performance gains?

FYI: Talked with mechanic that fixed my 08's oil leak by replacing pan gasket. He claimed he checked rear sea when pan was off and it was tight and had no leak. He too was surprised it was the pan gasket and not the rear seal. Hope he's right....

There are also the DOD lifters that people tend to think that the lifters can't take the abuse. I have a pic or two in my other thread of the DOD lifters.

[Andy@Livernois]

Is the DOD valve train problems you have alluded to in the past few weeks just this plastic tensioner, or is there other premature wear that you were thinking was due to tunes with 200 rpm or higher rev limit?

Where I am going is.... would one be better off modding heads to remove DOD and installing a hi-lift cam etc., or a MagnaCharger and keeping stock heads and cam that will yield similar performance gains?

FYI: Talked with mechanic that fixed my 08's oil leak by replacing pan gasket. He claimed he checked rear sea when pan was off and it was tight and had no leak. He too was surprised it was the pan gasket and not the rear seal. Hope he's right....
no, the DOD problems that we have seen include this, but most of it is lifter/oiling related. Like on Paul's car, we have seen alot of cars with premature wear on the cam bearings. If you really had to choose only one of those 2 mods? man you aren't making it easy. I guess it would depend on future mods later down the line... My gut reaction is to say scrap the DOD because of the wide array of issues people are seeing with it, but the maggie does have more capability in it too... All it takes is a pulley swap ;)



Since I'm using stock 18" rims Andy suggested that I try the Nitto Invo
245/45ZR/18 tire. It has the same diameter as the stock tire plus its supposed to be a lot stickier. I bought a set but haven't put them on the car to try out.
c'mon... you still ahven't put them on??? ;) I'll start calling you Charlie if you drag it out too much longer.



There are also the DOD lifters that people tend to think that the lifters can't take the abuse. I have a pic or two in my other thread of the DOD lifters.
yeah, the lifters can be a problem at higher rpm...

[Blackdevil77]

I'm getting the cam in the future like this summer sometime, but in the mean time, if i just turn of DOD, would that help or slow down some of these problems?

[Andy@Livernois]

I'm getting the cam in the future like this summer sometime, but in the mean time, if i just turn of DOD, would that help or slow down some of these problems?

unfortunately it's an inherent mechanical issue, the tune might help a little bit, but not entirely like the non-dod cam setup would.

[jbradsh1]

Since I'm using stock 18" rims Andy suggested that I try the Nitto Invo
245/45ZR/18 tire. It has the same diameter as the stock tire plus its supposed to be a lot stickier. I bought a set but haven't put them on the car to try out.

Get 'em on! I'd really like to hear some feedback from you as I'm getting ready to order wheels and tires next week! I'd really like to know just how quiet they are (hey, there's a surprise) at different speeds. Thanks.

[-Ray-]

no, the DOD problems that we have seen include this, but most of it is lifter/oiling related. Like on Paul's car, we have seen alot of cars with premature wear on the cam bearings. If you really had to choose only one of those 2 mods? man you aren't making it easy. I guess it would depend on future mods later down the line... My gut reaction is to say scrap the DOD because of the wide array of issues people are seeing with it, but the maggie does have more capability in it too... All it takes is a pulley swap ;)

c'mon... you still ahven't put them on??? ;) I'll start calling you Charlie if you drag it out too much longer.

yeah, the lifters can be a problem at higher rpm...


Andy:
Can you give us an idea on how many cars you've seen this on? If this is an event that could cause engine failure, it would be nice to get these reported to GM.
I'd like to know what the expected failure rate is for this component.
Thanks,
Ray

[EcoBrick Bob]

:poof::poof::poof: OOPS....

What was that rev limiter set at again????

Nearly new G8 For Sale, driven only on Sundays to Church and back, by gentle old Grandpa....

Believe I saw a post months ago with a link to a long article on our DOD system. Anybody have the address?

[Andy@Livernois]

Andy:
Can you give us an idea on how many cars you've seen this on? If this is an event that could cause engine failure, it would be nice to get these reported to GM.
I'd like to know what the expected failure rate is for this component.
Thanks,
Ray

Well, it really isn't gm's fault on th bearing wear, or the durability of the lifters at high rpm...

As far as the tensioner, I think we have seen it on about a dozen engines, most of which were sent to us after going through GM durability testing. The bearing wear stuff definitely seems to be RPM related. The only thing with the tensioner issue is that since it doesn't make noise, doesn't effect the way it runs, and really isn't externally detectable, how the hell can you convince the dealer to take a look? and it's not like you can tell them " hey, I was installing my aftermarket camshaft this weekend and saw this..."

[ronbuick]

So do we need to have to worry about this down the road at 10K, 30K or 100K
miles, also when should a person have or need to R&R a TC, thanks.

Ron

[-Ray-]

I have 17k miles on my G8. A few of it at 6200 rpm. Is the cam gear sintered metal? I'd hate to have mine go. Obviously I'm beyond warranty at this point in the mod cycle.

[Crazy Paul]

Not sure how the cam gear is made.
Stock set-up should look like this (except for the oil pump part number).


http://g.imagehost.org/0300/2792209582_fd2e9269e3_o.jpg

[g8_795]

Not sure how the cam gear is made.
Stock set-up should look like this (except for the oil pump part number).


http://g.imagehost.org/0300/2792209582_fd2e9269e3_o.jpg

So is there no pin in the stock setup? On the left side of the pic, top of the tensioner there is a hole that looks like a metal pin should go there. I don't think I see one in the pic. Even the plastic piece that use to be there had a pin hole in it. I have not been able to find this phantom pin...

[GRRRR8]

Robert, I assume you took off the oil pump to change the tensioner, but did you have to drop the pan to get the oilpump pickup tube off?

[g8_795]

Robert, I assume you took off the oil pump to change the tensioner, but did you have to drop the pan to get the oilpump pickup tube off?

Yes, I had to drop it about a half an inch.

[GRRRR8]

Thats what it looked like. I guess I might as well upgrade pump and chain then.

[g8_795]

Thats what it looked like. I guess I might as well upgrade pump and chain then.

I think that is a good idea. I know I would have pulled mine apart when I installed my UDP the first time if I knew there was a problem.

[Crazy Paul]

So is there no pin in the stock setup? On the left side of the pic, top of the tensioner there is a hole that looks like a metal pin should go there. I don't think I see one in the pic. Even the plastic piece that use to be there had a pin hole in it. I have not been able to find this phantom pin...

Sorry I don't know if there should be a pin. It could have fallen out of this one also.....or there never was one ?

http://g.imagehost.org/0487/2791359383_525b27c6d5_o.jpg

[g8_795]

Thanks for the pics. I looks like a pin should go there but who knows. Looks like a pretty poor design to me. I hope there isn't one there because that means I won't have a metal pin flinging around my engine somewhere.

[Crazy Paul]

I hope there isn't one there because that means I won't have a metal pin flinging around my engine somewhere.

Can't be any worse than the needle rollers that fall out of the rocker bearings.
:)

[BigV8]

These engines assembled in mexico? thought that was what the window sticker said, not that its a bad thing but it is a long way from home.

[Mike@NewEra]

Maybe there is no pin???? I just assumed there should be, but it is never there when I take a G8 apart, and that piece on the left side was sitting down in the front of my oil pan when I took mine out the first time, I think I had about 2500 miles on my car at the time believe it or not.

[BSmith]

Just an FYI, this doesn't sound too good on your shop's rep., not hating just wanted to let you know.

A lot of time a mechanic will let things slide on his own car that would never slide on a customers car. The risk is fine on your own car, but not on a customers. Torque specs fall into this category sometimes.

Saying you'd do it on your own car probably means it's important. ;)

[Zippy]

There is no pin. You are supposed to pin the tensioner to pull the chain out and put it back in. The pin is what you use to hold the tension off the chain. If I had one in front of me I'd take pictures to explain. After the chain is re-installed you remove the pin to replace the tension on the chain. There was likely a bad batch of tensioner pieces made. It is a good design although a pain in the ass for those who keep that design on there. It's there because the rougher running of the D.O.D. is hard on a timing chain and this is there to keep the chain from slapping around during 4 cylinder mode by keeping heavy tension on it at all times.

[Crazy Paul]

http://g.imagehost.org/0981/pin1_03.jpg

http://g.imagehost.org/0989/pin2_03.jpg

http://g.imagehost.org/0899/pin3_03.jpg

[-Ray-]

Thanks guys. Huge help here. A good enough reason the get a cam in my G8.

EDIT: after thinking about it, it's also a good reason to deactivate the AFM.

[g8_795]

Excellent. That is very good to know. I can quit worrying about metal in my block now.

[Crazy Paul]

As far as the tensioner, I think we have seen it on about a dozen engines, most of which were sent to us after going through GM durability testing. The bearing wear stuff definitely seems to be RPM related. The only thing with the tensioner issue is that since it doesn't make noise, doesn't effect the way it runs, and really isn't externally detectable, how the hell can you convince the dealer to take a look? and it's not like you can tell them " hey, I was installing my aftermarket camshaft this weekend and saw this..."

Logic would suggest that after the tensioner goes then the cam chain is able to whip around and potentially kill itself. Seen any cam chain failures on engines fitted with this brown tensioner assy ?

[Mike@NewEra]

There is no pin. You are supposed to pin the tensioner to pull the chain out and put it back in. The pin is what you use to hold the tension off the chain. If I had one in front of me I'd take pictures to explain. After the chain is re-installed you remove the pin to replace the tension on the chain. There was likely a bad batch of tensioner pieces made. It is a good design although a pain in the ass for those who keep that design on there. It's there because the rougher running of the D.O.D. is hard on a timing chain and this is there to keep the chain from slapping around during 4 cylinder mode by keeping heavy tension on it at all times.


This tensioner is used on the 2008 trailblazer SS which does not have DOD, and also on the 08 and newer vettes if I am not mistaken, which also do not have DOD. I agree with it being a good design, if it didn't fall apart.

[GRRRR8]

There is no pin. You are supposed to pin the tensioner to pull the chain out and put it back in. The pin is what you use to hold the tension off the chain. If I had one in front of me I'd take pictures to explain. After the chain is re-installed you remove the pin to replace the tension on the chain. There was likely a bad batch of tensioner pieces made. It is a good design although a pain in the ass for those who keep that design on there. It's there because the rougher running of the D.O.D. is hard on a timing chain and this is there to keep the chain from slapping around during 4 cylinder mode by keeping heavy tension on it at all times.

Beat me to it Zippy! You are correct, no pin.

[Andy@Livernois]

Logic would suggest that after the tensioner goes then the cam chain is able to whip around and potentially kill itself. Seen any cam chain failures on engines fitted with this brown tensioner assy ?

Not as of yet... I hope we never do either.

[Zippy]

This tensioner is used on the 2008 trailblazer SS which does not have DOD, and also on the 08 and newer vettes if I am not mistaken, which also do not have DOD. I agree with it being a good design, if it didn't fall apart.

I probably should have specified better. Like the blocks that are built with the D.O.D. capabilities, but not using it. The new tensioner is used in more than just D.O.D. applications. It's a new design that they want to use in everything. LOL I think that once they get the part superceeded a few times it'll be a great setup.

[Mike@NewEra]

I agree as well, when that happens.
BlackBerry9530/4.7.0.75 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/105

[KaiserM715]

I sounds like some of the LS3 Vette folks are having issues related to this also:

http://forums.corvetteforum.com/c6-tech-performance/2205820-2008-ls3-timing-chain-failure.html
Be warned, these guys get into an argument as to whether and under-drive pulley is the root cause, which I do not think is the problem...

There are also a couple of threads on LS1tech.

[Kaltech Tuning]

I've seen the tensioner break in an LS3 vette that head heads and cam and was driven hard. I've seen the instances of ls3 timing chains breaking on corvette forum. I will say that broken timing chains can be like the old which came first, chicken or egg question. In these instances is the chain breaking first or is something else breaking and causing the chain to break.
There seem to be more instances of broken timing chains (no matter what the cause) on LS3's than LS1/LS2's and the LS1/LS2's don't have this type of tensioner. Makes me wonder if these tensioners are falling and causing timing chain problems. THAT'S PURE SPECULATION but it's quickly starting to seem like there are too many coincidences with these timing chains and tensioners.

[jbradsh1]

That's one of the reasons I decided to go ahead and get the cam installed right away. Bullit proof cam tensioner gets installed.

[pha|anx]

so in theory, if you weren't doing a cam and staying stock an LS2 timing chain set would rectify this problem? am I reading this alright?

[GRRRR8]

LS2 chain tensioner. I changed the chain and tensioner in mine while it was apart.

[Andy@Livernois]

n/m, should have hit refresh... charlie beat me (for once ;) )

[GRRRR8]

n/m, should have hit refresh... charlie beat me (for once ;) )

Thats the problem with them Buicks, you gotta SPOOOOOOLEM up! lol

[MitsukiGT]

Would a LS2 timing chain set void the warranty? I'd imagine so. What can we do about it?

Has ANYONE seen one that was NOT broken when they installed their cams? I don't see me getting 200K out of that design, it appears 20K is out of the question :'(

[Andy@Livernois]

the last 2 cars we did were not broken... I dont recall the mileage amount on Jeff's, but it's his every day car, Roy's has very low miles so I didn't expect it to be broken either...

[MitsukiGT]

Andy, what would it cost to install a LS2 timing chain set from you? Seem like this will be a must have after I get that blower.

[Andy@Livernois]

well, really the tensioner is the difference...

It runs 29.99

[edmanet]

the last 2 cars we did were not broken... I dont recall the mileage amount on Jeff's, but it's his every day car, Roy's has very low miles so I didn't expect it to be broken either...

My car only had 1360 miles on it.

[edmanet]

well, really the tensioner is the difference...

It runs 29.99

And it costs $3000 to install
LMAo

[MitsukiGT]

And it costs $3000 to install
LMAo

Damn, might as well run until the warranty is up and hope it causes a problem before then. LOL or I could buy all the tools to do it myself. Hell, I might as well buy a new CAM if I had that changed.

[edmanet]

Damn, might as well run until the warranty is up and hope it causes a problem before then. LOL or I could buy all the tools to do it myself. Hell, I might as well buy a new CAM if I had that changed.

You might as well. That's what I did.

http://forum.grrrr8.net/showthread.php?t=4374