Well i broke a rocker arm.....
01-27-2016, 02:19 PM
#11
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robert
01-27-2016, 02:19 PM
#12
Well something Was out of spec.. 
01-27-2016, 02:21 PM
#13
The failure may have been an accumulation of over-revs or retainer/keeper failure over time. The simple 3rd to 4th shift was the straw that broke the camel's back.
01-27-2016, 03:09 PM
#14
Pretty much the same thing happened to my old motor. It gave out near the top of 3rd, about 8k rpm. Broke both rockers on the intake side of cyl 2 and 1 valve on the exhaust side of cyl 2. Both valves are sunk in the retainers on intake side. I never got around to pulling the head off.
The motor did have ap2 retainers on the intake side. Had a used oil analysis done after a track day and it had a lot of lead(a little over a month before it blew up). Not sure if that had anything to do with the failure but i knew something was wrong. I was planning to get a daily beater and pull the motor apart to see if i could rebuild it but it didnt last.
The motor did have ap2 retainers on the intake side. Had a used oil analysis done after a track day and it had a lot of lead(a little over a month before it blew up). Not sure if that had anything to do with the failure but i knew something was wrong. I was planning to get a daily beater and pull the motor apart to see if i could rebuild it but it didnt last.
01-27-2016, 05:55 PM
#15
Originally Posted by postman' timestamp='1453936022' post='23864408
Based on his description I'd chalk it up to a faulty rocker arm. Sometimes shit happens. Constant high rpms rarely cause an issue on these engines, and the pcm would have prevented an over rev at that time.
The failure may have been an accumulation of over-revs or retainer/keeper failure over time. The simple 3rd to 4th shift was the straw that broke the camel's back.
Or when the rocker broke it wedged itself on top of retainer and caused the valve to hit piston. Ultimately no one will ever no the real reason.
01-27-2016, 06:36 PM
#16
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i suspect u had a tight valve, and i think that is why only 1 rocker arm broke
This is my theory:
Valve got pushed too far and hit the piston, then the piston bent the valve but it actually broke the valve into half, and then the rest of the valve rocket launched into the tappet and it forced the rocker arm pull backward and got stretched out as the cam lobe was turning.
and ofc the valve knocked the spark plug and melt it..
can u take a clean pic of ur valve tappet?
is it beat up bad? valve looks smashed. but pics are too blurry to tell.
take a close up pic of retainer top and bot.
4th to 3rd is no good especially when u r in redline
This is my theory:
Valve got pushed too far and hit the piston, then the piston bent the valve but it actually broke the valve into half, and then the rest of the valve rocket launched into the tappet and it forced the rocker arm pull backward and got stretched out as the cam lobe was turning.
and ofc the valve knocked the spark plug and melt it..
can u take a clean pic of ur valve tappet?
is it beat up bad? valve looks smashed. but pics are too blurry to tell.
take a close up pic of retainer top and bot.
4th to 3rd is no good especially when u r in redline
01-27-2016, 07:39 PM
#18
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I check the valve lash less than 2k Miles ago. I only needed to adjust 1 valve all was still in spec.
01-27-2016, 07:42 PM
#19
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I guess I got the loss on this one.
As for oil I use ams oil dominator and change before and after each track event and every 1k miles.
01-27-2016, 07:44 PM
#20
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I care a lot for reliability.
I have my data log for the infinity and sent it to my tuner.