You guys were right... It was the timing chain
03-18-2012, 08:15 AM
#1
Track Junky
Thread Starter
You guys were right... It was the timing chain
Posted a thread last week about going off the track due to a cam position sensor failure. Got the engine cover off last night and guess what? Timing chain all bunched up under the oil pump.
You guys nailed it right on the head! the Heads took all the damage as 13 of 16 valves made contact. Pistons are hurt but probably not out of the game and cylinder walls still look good - no scratches, no gouges, no nothing.
Thanks for your diagnostic help last week. Got a new LS3 dry sump on the way. I know it's not the perfect road race motor, but it's definitely a step up from my previous wet sump. Hopefully I can move up to a true dry setup in the next few years when I think I'm ready to compete or do TT.
Sean
You guys nailed it right on the head! the Heads took all the damage as 13 of 16 valves made contact. Pistons are hurt but probably not out of the game and cylinder walls still look good - no scratches, no gouges, no nothing.
Thanks for your diagnostic help last week. Got a new LS3 dry sump on the way. I know it's not the perfect road race motor, but it's definitely a step up from my previous wet sump. Hopefully I can move up to a true dry setup in the next few years when I think I'm ready to compete or do TT.
Sean
03-18-2012, 09:12 PM
#4
Race Director
Posted a thread last week about going off the track due to a cam position sensor failure. Got the engine cover off last night and guess what? Timing chain all bunched up under the oil pump.
You guys nailed it right on the head! the Heads took all the damage as 13 of 16 valves made contact. Pistons are hurt but probably not out of the game and cylinder walls still look good - no scratches, no gouges, no nothing.
Thanks for your diagnostic help last week. Got a new LS3 dry sump on the way. I know it's not the perfect road race motor, but it's definitely a step up from my previous wet sump. Hopefully I can move up to a true dry setup in the next few years when I think I'm ready to compete or do TT.
Sean
You guys nailed it right on the head! the Heads took all the damage as 13 of 16 valves made contact. Pistons are hurt but probably not out of the game and cylinder walls still look good - no scratches, no gouges, no nothing.
Thanks for your diagnostic help last week. Got a new LS3 dry sump on the way. I know it's not the perfect road race motor, but it's definitely a step up from my previous wet sump. Hopefully I can move up to a true dry setup in the next few years when I think I'm ready to compete or do TT.
Sean
03-18-2012, 09:25 PM
#5
Track Junky
Thread Starter
03-18-2012, 11:24 PM
#8
Race Director
There is a service procedure to match the balance of the new pully to the (factory) balance of the original. Using weights. Many technicians (even Vette specialists) are not aware of this. It's in the FSM.
Do you know if the installer followed the procedure?
Just trying to learn more for everyone.
Last edited by froggy47; 03-18-2012 at 11:28 PM.
03-19-2012, 07:39 AM
#9
Track Junky
Thread Starter
What % under was it?
There is a service procedure to match the balance of the new pully to the (factory) balance of the original. Using weights. Many technicians (even Vette specialists) are not aware of this. It's in the FSM.
Do you know if the installer followed the procedure?
Just trying to learn more for everyone.
There is a service procedure to match the balance of the new pully to the (factory) balance of the original. Using weights. Many technicians (even Vette specialists) are not aware of this. It's in the FSM.
Do you know if the installer followed the procedure?
Just trying to learn more for everyone.
Expensive mistake, huh?
03-19-2012, 09:30 AM
#10
Safety Car
No... it's just not very good at dampening crank harmonics which is it's primary purpose.
There's no good way to do this with an aftermarket balancer. I've been fine installing ATI superdampers as they come out of the box, zero vibration issues. Now on a clutch I will have that match balanced to the OEM one that comes off. I've been bit before by installing a zero balanced clutch assembly on an old car where it had an off-balanced one from the factory on purpose to bring everything within spec.
What % under was it?
There is a service procedure to match the balance of the new pully to the (factory) balance of the original. Using weights. Many technicians (even Vette specialists) are not aware of this. It's in the FSM.
Do you know if the installer followed the procedure?
Just trying to learn more for everyone.
There is a service procedure to match the balance of the new pully to the (factory) balance of the original. Using weights. Many technicians (even Vette specialists) are not aware of this. It's in the FSM.
Do you know if the installer followed the procedure?
Just trying to learn more for everyone.
03-19-2012, 12:16 PM
#11
Race Director
I have heard a rule of thumb to not go over 10% reduction.
Travisnd may be right, the FSM balance procedure is stock for stock.
I thought the ATI has some "built in" balancing feature that adjusts it the first time you go to 2500 rpm or something like that?
Last edited by froggy47; 03-19-2012 at 12:18 PM.
03-19-2012, 12:34 PM
#13
Le Mans Master
No... it's just not very good at dampening crank harmonics which is it's primary purpose.
There's no good way to do this with an aftermarket balancer. I've been fine installing ATI superdampers as they come out of the box, zero vibration issues. Now on a clutch I will have that match balanced to the OEM one that comes off. I've been bit before by installing a zero balanced clutch assembly on an old car where it had an off-balanced one from the factory on purpose to bring everything within spec.
There's no good way to do this with an aftermarket balancer. I've been fine installing ATI superdampers as they come out of the box, zero vibration issues. Now on a clutch I will have that match balanced to the OEM one that comes off. I've been bit before by installing a zero balanced clutch assembly on an old car where it had an off-balanced one from the factory on purpose to bring everything within spec.
03-29-2012, 05:33 PM
#15
Le Mans Master
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
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Tech Contributor
St. Jude Donor '11-'12-'13-'14
Hey Sean, I was just reading this and now it's got me a little paranoid on my chain. I remember it was in a Katech bag but that's it.
http://forums.corvetteforum.com/c6-t...-the-c5-r.html
http://forums.corvetteforum.com/c6-t...-the-c5-r.html
03-29-2012, 07:20 PM
#16
Track Junky
Thread Starter
I bought mine Directly from Hinson. If they sold me a low grade chain I have bigger issues to deal with as I bought my new motor from them. Seriously doubt that's the case as Brian told me he buys directly from Katech. I believe that the ASP pulley was the cause after talking to Jason Katech.
You aren't running ASP UD pulley, are you?
You aren't running ASP UD pulley, are you?
03-30-2012, 08:01 AM
#17
Le Mans Master
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
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Tech Contributor
St. Jude Donor '11-'12-'13-'14
No sir, Powerbond here. I have a picture of the parts that went in my car and you can clearly see the Katech logo on the timing chain. I didn't take any close up pictures of it though. I'm pretty sure Cajun got everything from either Hinson or SDPC but I can't remember which one.
