Hey,
I decided to pull off the valve cover the other day to clean it up and do my dismay I found this....
Needless to say I'm not impressed right now.
I'm running the Supertech 78lbs valve spring kit with their titanium (dished) retainers. I am also running Comp Cams Stage 2 N/A cams.
As you can see by the photos the rocker arm is touching on the retainer. It so happens that my Sunfire is a 2005, which means it shares the machined rockers from an LSJ as apposed to the stamped rocker arms found in the 02-04' L61's.
Now for the weird stuff......
This is only happening on the exhaust side, and only on 4 of the 8 retainers....there is no particular pattern to which ones are rubbing either.
Any one have any idea why this would be happening???
Or why this is only happening on the exhaust side....and only some of them on top of that?
Only thing I can think of is some of my rockers are bent...but then again why only the exhaust side and why only a few of them?
I'm stumped.
Any help would be much appreciated!
Did you have a valve-job done when everything was put together??? If so, a common procedure done by machine shops is to compensate for valve and seat grinding by machining some material off of the end of the valve stem. Basically, when a valve and seat are machined, it raises the valve up into the head. This also causes the valve stem to stick up that much more making it "taller", and could cause valve lift changes, even to the point that on some solid lifter engines, it would prevent the valve from closing all the way. Machining the tip of the valve stem to compensate for the "taller" stem prevents this from happening. It sounds to me like the tip that sticks up past the valve keepers isn't tall enough on the damaged retainers, therefore causing the rocker and retainer to make contact. IMO, either they were machined down too much by a shop, or were made incorrectly. I have the 05 lifters and complete Supertech valvetrain setup as well. No interference problems here.
Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!
Shiat that looks weird, sux to see.
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Roofy wrote:Did you have a valve-job done when everything was put together??? If so, a common procedure done by machine shops is to compensate for valve and seat grinding by machining some material off of the end of the valve stem. Basically, when a valve and seat are machined, it raises the valve up into the head. This also causes the valve stem to stick up that much more making it "taller", and could cause valve lift changes, even to the point that on some solid lifter engines, it would prevent the valve from closing all the way. Machining the tip of the valve stem to compensate for the "taller" stem prevents this from happening. It sounds to me like the tip that sticks up past the valve keepers isn't tall enough on the damaged retainers, therefore causing the rocker and retainer to make contact. IMO, either they were machined down too much by a shop, or were made incorrectly. I have the 05 lifters and complete Supertech valvetrain setup as well. No interference problems here.
There was no machining done to the head, I actually just swapped the valve springs with the head still on the engine.
Everything is stock minus the cams and springs.
Do you have the 78lb kit?? I know they offer a few different pressures, not sure if the design is different between them tho.
wow... for something to dig into titanium like that it would take a lot.
sucks to see man, make sure all the clearances and everything spec out.
id call supertech and ask them wtf they think is up.
180hp in 1989 or 145hp in 2002, you decide. >
Ya I'll have to give them a call, I'm pretty sure the issue is on my end however.
Like I said the only thing I can think of is that the rocker arms are bent.
I once mis-shifted at the track at the beginning of last year, instead of 3rd -> 4th, I went 3rd -> 2nd. The motor had no signs of damage at the time and never has an issue arose since then, until now that is.
But I'm not sure if that is even the cause of all this.
Why would only a few of the rocker arms bend on the exhaust side and not the rest of them? Or why none on the intake side bent?
Could over-reving the motor even lead to bend rocker arms?
So many questions, so few answers....lol
Interesting...was this happening on all the valves?? or just certain ones?
Mine are they same way...it looks really bad in the photo, but if you run your finger nail across you can barely feel the marks.
Thats pretty common for Titanium retainers, steel is much better.
what do the lifters/ lash adjusters under the troubled rocker arms look like?
it was hit or miss on them since they shaved all the ones that were touching at the time. now its all clearing and no problems.
PJ - It actually looked fine underneath the rocker. I was expecting wear marks but it was fine....which is strange.
BuiltNBoosted - Ahh ic, shaving them down is the route I think I'll be taking as well.
also, I wouldn't say the rockers are bent until you pull them out and compare to good ones...
does the car make any valvetrain noise? I would imagine those rockers are only hitting when closed...
easiest solution would be to clearance the bottom of the rocker, although you have to think you'd probably be sacrificing a bit of rocker integrity, and thats only fixing the result of your problem not the cause... whatever that may be.
I doubt the mis-shift bent any of the rockers. The 78lb kit is rated to 9000 rpm I think. And you would more likely bend a valve or break a lifter than a rocker. You would also have weird wear patterns in the rocker and cam too if the rocker was bent.
Currently #4 in Ecotec Forced Induction horsepower ratings. 505.8 WHP 414WTQ!!!
Currently 3rd quickest Ecotec on the .org - 10.949 @ 131.50 MPH!!!
the stuff in my head here is fine...
LE61T PTE6262 Powered
No valve train noise, everything sounds normal.
I think I'll be clearance-ing the rockers for now, unless I pull them out and they are bent, in which case I'll replace them.
vince... wow, did todd actually do that? if so ive lost some of my faith in him... surely he could have used a lathe or something to get a more professional cut. that does not seem like todd miller to me.
180hp in 1989 or 145hp in 2002, you decide. >
z yaaaa wrote:vince... wow, did todd actually do that? if so ive lost some of my faith in him... surely he could have used a lathe or something to get a more professional cut. that does not seem like todd miller to me.
They clearanced them as they put them in, dremeled down the ones that were touching at the time. if they werent touching at that time, didnt need shaved. and what exactly would he have lathed? Its completely custom valve train. Jon came, free of charge, spent a few hours pulling off the ones that were touching, dremeled them down, re-installed them. and no issues since. when they built the motor, they took all the casting marks off of the rockers before installing and also drilled some extra oiling passages on the exhaust side to spray oil on the valve train at high rpm.
and like i said, it looks like they are 30 feet deep yet when you run your nail over them, you cant even feel the marks at all. plus the marks only went to prove that the springs were rotating in the seat which is good.
i still have 100% faith in todd and jon and this motor, and im going to push it to its max in its current form.
Update:
Pulled the valve cover off last night to check the situation of this and sorta good news I guess.
From what I can tell by looking at the pictures I took before there has been no additional wearing since I last checked.
The wearing must have happened at initial start up and self clearanced itself at that time.
Still unsure what caused them to rub in the first place, but considering it has stopped its not really worth my time to rip it all apart to fix a problem that has solved itself.
I'll check it periodically to see if it does start to get any worse, and hope for the best. Probably have the motor opened up again in the spring anyways.
well thats good, I am going to run comp stage 2 and the 78 lb kit myself so was worried a little bit
LE61T PTE6262 Powered
Each one will probably be different becauet the casting and marks on each rocker are slightly different.
When the motor was built I took each rocker and took the casting marks out with a dremel/small belt sander to prevent cracking under high rpm, this was the recommendation of Roush racing and what they did to their motors. They did not specify that they also did this for clearance for the top of the retainers. When Vincent showed me the photos above we took some more material out of each rocker. While they had probably done any and all damage they were going to do, like you mentioned not seeing any more I still wanted to be sure. Regardless if it were left alone at this point you're right, it probably won't hurt anything.
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