Exhaust valves hitting pistons?
- Thread starter summ8rmk
- Start date
Considering there is a stop built into the valve so this does not happen . Is there a lot of miles .
To fix it I would grind those corners off in a way that just takes the radius to the sides more.
To fix it I would grind those corners off in a way that just takes the radius to the sides more.
I'm going to look at some 09 cyl and valves in the garage tomorrow .
I'm pretty sure the valves would have to beat an indentation into the cyl for this to happen
I'm pretty sure the valves would have to beat an indentation into the cyl for this to happen
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Grind the edges of the power valve and/or double gasket the power valve.
Look at the cylinder where the power valve sits, you will see that the cylinder is indented- or worn causing the power valve to contact the piston.
Look at the cylinder where the power valve sits, you will see that the cylinder is indented- or worn causing the power valve to contact the piston.
This is Exactly what happens.
There is a couple thousandths wear on the cylinder.
I'm just going to massage the valve a little put new pistons in and I should be good for another 4,000 miles.
The sled ran fine. Still 53mph track speed at 6,900 ft. My buddies pro's and xm's were 45-47 mph.
ridin da yamacat
I'm just going to massage the valve a little put new pistons in and I should be good for another 4,000 miles.
The sled ran fine. Still 53mph track speed at 6,900 ft. My buddies pro's and xm's were 45-47 mph.
ridin da yamacat
x2 do both !
haha I was drinking beer last night 
Exhaust valves are several thousandths away from from piston when fully closed.
The valve is closed and u cant even see it when looking straight down in to the cylinder.
Could high EGT cause the valve to expand in to the cylinder?
ridin da yamacat
The valve is closed and u cant even see it when looking straight down in to the cylinder.
Could high EGT cause the valve to expand in to the cylinder?
ridin da yamacat
Are you talking the gasket where the power valve meets the cylinder? I would think if you added a gasket there it would shim the power valve away from the piston.
The other gasket at top gasket where the cable meets the power valve I could see where that wouldn't work adding gaskets.
Your not the only one with this problem, do a search. There is a few threads about this.
That tab beats the hell of of that slot and eventually the valve will put a indent is the slot causing the valve to hit the piston. So, either add some material to the slot, or the tab, or double or triple the gasket to move the valve back out to where it is supposed to be.
This issue has been hashed out on here many times. maybe you could find some older posts for a little insight.
This issue has been hashed out on here many times. maybe you could find some older posts for a little insight.
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I shortened the overall length of the valves with a spinning stone and textured paper. If they hit again then I have serious problem.
It honestly looks like the valve would have to rock side to side for it to protrude past the cylinder wall.
ridin da yamacat
It honestly looks like the valve would have to rock side to side for it to protrude past the cylinder wall.
ridin da yamacat
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Pull the valve blades and weld more material to the base. Then grind straight. Just an idea, never done itThis tab
Rests in to this slot.
ridin da yamacat
