WHAT CAUSED THIS ROCKER ARM TO BE BEAT UP

[ShadowBolt]

This was on the intake valve of number eight. The hole I was having oil trouble with. The top of the valve spring cap (or whatever it's called) looks perfect (as I assumed it would since it's made from steel and the rocker is made from aluminum). All the rest of the rockers were perfect.




Here is a pic of the hole with the deep scratches.



JJ

[AI#97]

Thankfully your Driving talent exceeds your photography skills!!

Rocker looks like the top of the valve either "compressed" and left, the retainer bent or the valve is walking side to side in the guide and the rocker was moving around as the valve floated...

If the valve stem is moving horizontally due to a bad guide, you would have serious oil problems in that cylinder as the valve stem seal would be incapable of dealing with that much horizontal movement....

I would suggest new valve guides, a valve job that is legal and all new valve springs and retainers. Sounds like you are getting into an engine that has needed a lot of TLC for quite some time! :cry:


edit: figured out the pictures were a LOT larger than my phone could see!

[ShadowBolt]

Thankfully your Driving talent exceeds your photography skills!!

Rocker looks like the top of the valve either "compressed" and left, the retainer bent or the valve is walking side to side in the guide and the rocker was moving around as the valve floated...

If the valve stem is moving horizontally due to a bad guide, you would have serious oil problems in that cylinder as the valve stem seal would be incapable of dealing with that much horizontal movement....

I would suggest new valve guides, a valve job that is legal and all new valve springs and retainers. Sounds like you are getting into an engine that has needed a lot of TLC for quite some time! :cry:


edit: figured out the pictures were a LOT larger than my phone could see!

I don't know why the pics posted up so large. The valve guides look and feel fine. I guess this rocker arm could have been screwed up from another install but this was the hole that was getting oil in it. The rocker arm is fine everywhere except where it's chewed up on the sides. The roller is still free and feels good. I agree we were lucky to finish every race last season. What do you mean a legal valve job? Is there any other kind?


JJ

[AI#97]

What do you mean a legal valve job? Is there any other kind?


JJ

There are several types of Performance valve jobs...just make sure the machine shop doesn't do a 5 angle valve job if it isn't legal in CMC/2. Not like anyone could tell visually unless they tore you down.

[marshall_mosty]

How's this?

[mitchntx]

There are several types of Performance valve jobs...just make sure the machine shop doesn't do a 5 angle valve job if it isn't legal in CMC/2. Not like anyone could tell visually unless they tore you down.

Good luck finding a decent and reputable machine shop that DOESN'T do multi-angle valve jobs.

[AI#97]

Well, after reading the 2009 CMC rules, I don't recall seeing anything that prevented 5 angle jobs...?

As for the piston wall jerry, looks like any other high mileage 5.0. Unless it was way down on compression, I might just put the sucker back together and run it! :P

[ShadowBolt]

Well, after reading the 2009 CMC rules, I don't recall seeing anything that prevented 5 angle jobs...?

As for the piston wall jerry, looks like any other high mileage 5.0. Unless it was way down on compression, I might just put the sucker back together and run it! :P

Matt,

You can't see the scratches in that hole but they are there. This is the only one down on compression and the one with oil in it. Rebuilding the whole thing as soon as the parts get here. I was trying to figure what caused the rocker arm damage.


Mitch,
Do the factory heads not have a three angle valve job?

JJ

JJ

[GlennCMC70]

Matt - thats the point, the rules dont say you can, thus its prevented.

Jerry - 3 angle valve jobs are the norm, that will be fine.

[AI#97]

Matt - thats the point, the rules dont say you can, thus its prevented.

Jerry - 3 angle valve jobs are the norm, that will be fine.

I realize that Glenn, but after the rules were restructured VERY similar to AI rules...it leaves a lot to be read in between the lines....especially with NO detailed way of determining compliance on practically anything other than track width....and as I recall, it doesn't tell you HOW track width would be measured... AI rules atleast say with toe plates 3" above the pavement and averaged. While I like the fact they reorganized the rules, there are HUGE holes in them from what I read this weekend. It might be the fact they are formatted SO much like the AI rules, I might just have started reading them like the AI rules which could be very confusing for newbs... Just a thought.