stuck valve adjuster screws

hey all,

i just gave my bike a sort of tune-up...i don't have a timing light or carb sync set. but i did adjust the point, cam chain tensioner, and the valve clearance. what a world of difference! it sounds different, goes faster, and runs better into higher rpms.

however, the left valve adjuster screws on each side of the bike (so on the right side, the rear adjuster. left side, the front adjuster) are stuck really hard. so much that it was starting to bend the screwdriver. i was thinking about getting a strip of metal to put in there to get some more torque but i don't know if i'll hurt anything. the adjuster screw itself isn't the strongest either; i don't want to break it.

can anybody provide some suggestions?

thanks,
aaron

try tapping the end of the adjuster with a hammer to try and "jar" it loose. some of those get pretty corroded over time.

You are loosening the nuts before attempting to adjust the screws, right?

If so and the screws are still stuck solid, try spraying some PB Blaster or similar product on them (a little bit mixed in with the engine oil shouldn't hurt anything) and let them sit over night and try again.

If that fails, best bet would be to remove the entire valve cover (not just the screw cover caps) to get a better look and angle on how to break them loose without damaging something.

RetroRiceRocketRider wrote:

You are loosening the nuts before attempting to adjust the screws, right?...

BINGO!
:laugh:

unfortunately, i had loosened the screws:laugh:
i'd prefer it to be a dumb mistake on my part.
i'll give those suggestions a try. i'm not going to make the engine fall apart by removing the real deal valve cover, right?

smockron wrote:

unfortunately, i had loosened the screws:laugh:
i'd prefer it to be a dumb mistake on my part.
i'll give those suggestions a try. i'm not going to make the engine fall apart by removing the real deal valve cover, right?

Hey, at least you didn't (hopefully) break anything, right?

Just get yourself a set of THESE , and it will make the job soooooo much easier.

If the PBBlaster and tapping methods fail to loosen the adjuster screws, here's another loosening theory that may not work either but won't hurt anything after the valve cover has been removed, if the parts fitment will allow it.

Remove the lock nut, etc. to allow fullest access to the adjusting screw. Have a screwdriver on hand that perfectly fits the adjusting screw slot. Obtain and use a piece of dry ice to hard freeze the tip end of the screwdriver. Use a pencil butane torch to heat the joint holding the adjusting screw. Then quickly use the frozen screwdriver in attempt to loosen the adjusting screw.

The theory is that the cold will first transfer to the screw allowing removal from the hot surrounding threads. You know -- expansion and contraction of metal with heat and cold, and all that stuff. Supposing regular ice with salt might also serve cooling function, but not nearly so much as dry ice.

And, yes, I know . . . but just consider it an act of desperation. :lol:

Good Luck!

Ok, wow, that's weird then. I mean these things aren't evern real "screws", per se. They are just shafts with o-rings. Really the only thing that even hold them in is the o-rings, once the outer plate (where the nuts are) is removed. there isn't even any metal-to-metal contact in the shaft hole.

Normally, in order to replace the o-rings, you just get some pliers and pull them out. I know its usually hard to pull them out, but I can't imagine what would be holding them so firmly in place...

Biquetoast wrote:

Ok, wow, that's weird then. I mean these things aren't evern real "screws", per se. They are just shafts with o-rings. Really the only thing that even hold them in is the o-rings, once the outer plate (where the nuts are) is removed. there isn't even any metal-to-metal contact in the shaft hole.

Normally, in order to replace the o-rings, you just get some pliers and pull them out. I know its usually hard to pull them out, but I can't imagine what would be holding them so firmly in place...

Guess that means using dry ice on the pliers :woohoo: Admittedly just grasping at straws -- anything to help loosen the hold.

I put some PB Blaster on them. I got one of them to move. Still couldn't get the other to move though even after about 5 applications of the Blaster. The valve clearance is a tight 0.08mm. It should be in the range of .10 to .15mm.

As Biquetoast advises -- these things aren't evern real "screws", per se. They are just shafts with o-rings. Really the only thing that even hold them in is the o-rings, once the outer plate (where the nuts are) is removed. there isn't even any metal-to-metal contact in the shaft hole. Normally, in order to replace the o-rings, you just get some pliers and pull them out. I know its usually hard to pull them out, but I can't imagine what would be holding them so firmly in place.


Three second removal process (after valve cover removed, and nuts and adjuster plate removed).

Tick -- heat with torch.

Tick -- touch end of adjuster screw with dry ice.

Tick -- use pliers to pull out adjuster screw.

OR NOT !

Post edited by: Patton, at: 2008/01/31 10:06