Does this show that my valvetrain geometry is off?

[mtocrs1]

Just like the title says. I know that there is an oil supply issue to this rocker arm on start up but the wear is on the outer edge of valve. Is it normal for the rocker arm to be that close to the edge of valve?

 

[84BuickGNYorkPA]

hard to see, is the top of valve still flat out to the edge? How many miles on the motor?

Chuck

 

[mtocrs1]

The valve is flat until it starts to taper off, however i dont think there should be a taper. It looks hard to see because the taper is so shinney. The hard to see part is the problem.

 

[SHADOWII]

Put the ...

rocker shaft back on to see if the rocker is setting where it should. Check the rocker for too much side to side play and the pad that ride on the valve stem. Check for bent valve, broken spring, rockers in correct order on the shaft?

 

[KL Mallender]

Aftermarket parts can be a real pain when working with a Buick,
I have several suggestions, but it really depends on whether you have the proper springs in there for the camshaft/lifter combination.
Some(and yours appear to be) retainers have a recessed collet area to allow for higher spring installed height, thypically the 1.28-1.36 diameter versions, which can cause interference between outer edge of retainer and inner arc of the rocker arm, you would like to see at least a minimum of .070 thousanths at closest contact(valvetrains "wiggle" around quite a bit).
The only real way to put a "proper" valve spring in a Buick is to remove heads and have spring seat area cut for 1.43-1.48 diameter springs, which offer just about any rate needed while also allow higher lifts before coil bind.
I have never seen a 1.7 installed height spring(typically 1.24-1.28 diameters) that offered adequate seat pressure(100-130 lbs) that didn't have over 350+ lbs when approaching maximum lift of camshaft, which does not leave enough room for coil bind clearence where spring pressure goes to the moon.
Stock Buick geometry was built for .450 maximum lifts...period.
Yet most camshafts people try to run are .480 and above, not surprising that there so many problems with cam lobe failures/retainers hitting guides/roller tips falling off valve edges.
So much for simple reply(sorry)

If you are running a flat tappet/hydralic cam, get the proper retainers and get rid of the spring shims.
Good luck.

Kevin.

 

[EVIL]

I enlarged it for you

 

[KL Mallender]

Thanks Evil, actually, it looks as if maybe the valve seat is recessing(erroding) or the valve itself is "tuliping", that valve end looks quite higher than the rest.
Might be time to "pull" the heads and get it corrected before dropping valve into piston while running, deffinately a bad day then.


Kevin.

 

[mtocrs1]

Aftermarket parts can be a real pain when working with a Buick,
I have several suggestions, but it really depends on whether you have the proper springs in there for the camshaft/lifter combination.
Some(and yours appear to be) retainers have a recessed collet area to allow for higher spring installed height, thypically the 1.28-1.36 diameter versions, which can cause interference between outer edge of retainer and inner arc of the rocker arm, you would like to see at least a minimum of .070 thousanths at closest contact(valvetrains "wiggle" around quite a bit).
The only real way to put a "proper" valve spring in a Buick is to remove heads and have spring seat area cut for 1.43-1.48 diameter springs, which offer just about any rate needed while also allow higher lifts before coil bind.
I have never seen a 1.7 installed height spring(typically 1.24-1.28 diameters) that offered adequate seat pressure(100-130 lbs) that didn't have over 350+ lbs when approaching maximum lift of camshaft, which does not leave enough room for coil bind clearence where spring pressure goes to the moon.
Stock Buick geometry was built for .450 maximum lifts...period.
Yet most camshafts people try to run are .480 and above, not surprising that there so many problems with cam lobe failures/retainers hitting guides/roller tips falling off valve edges.
So much for simple reply(sorry)

If you are running a flat tappet/hydralic cam, get the proper retainers and get rid of the spring shims.
Good luck.

Kevin.

Thanks for the replies. The heads were originally set up by Kenne Bell for his "turbo cam". After wiping two of those flat I went with a Bowling green customs grind. So I guess in reality no the heads were not set up for the cam but that was 10 years ago and I think the grinds were close.
I would like to reiderate that this rocker arm has delayed oil flow on engine start. I think the lifter is bad and bleeding down. I really think that the wear is being caused by the delayed oil flow but why on the valve edge? What do you use to mark where the rocker comes in contact with the valve? Some sort of machinist dye? This side of the engine has always seemed "clickety".

 

[KL Mallender]

Hi Motocrs1, when it boils down to modifying anything, you or I are the "final say", if we accept the parts and assemble them without checking clearences for ourselves, then you and I are at blame, this is called "assumed risk", I and others have only these pictures to comment on, untill you can measure valve stem contact height accuractly('cause it looks as the exhaust valve in question is standing higher) nobody will have the accuracy to base a statement on.
Hope for the best, but always prepare for the worst, life is made of checks and balances, the mechanical world is nothing more than yes or no physics, scream all ya want about possibilities, mechanical/physics only concern is what is available, no can run out of bounds and get away 'scott free'.
good luck,

Kevin.

 

[mtocrs1]

KL Mallender.
I put a straight edge over the top of all the valve stems and this valve is deffinatly higher than the rest. Looks like you are correct. Good call! What can cause the valve to tullip? And for the next question. Does anyone know of a good machine shop in central Illinois. Time to get the heads redone and install a roller cam.