Broken valve cotter

Man, I must be hard on my bike. Now the "valve cotter" has broke on the right intake valve. I lost compression and took my valve cover off to check it out. The cotters were sitting at the bottom of the spring recess. I had a heck of a time getting the cam cover off, too. One was squashed almost completely flat. Anyone have an idea what would cause something like this? Here's a picture of a valve cotter it. It's #10 on the drawing. http://home.cfl.rr.com/bumar/valve%20cotter.jpg

Thanks,

Rich

[This message has been edited by Rich in Orlando (edited 03-15-2001).]

Originally posted by Rich in Orlando:

Man, I must be hard on my bike. Now the "valve cotter" has broke on the right intake valve. I lost compression and took my valve cover off to check it out. The cotters were sitting at the bottom of the spring recess. I had a heck of a time getting the cam cover off, too. One was squashed almost completely flat. Anyone have an idea what would cause something like this? Here's a picture of a valve cotter it. It's #10 on the drawing. http://home.cfl.rr.com/bumar/valve%20cotter.jpg

Thanks,

Rich

[This message has been edited by Rich in Orlando (edited 03-15-2001).]

I worked at a custom valvetrain manufacturer for a few years and there are a few ways that I have seen keepers spit out.

#1 Insufficient valve protrusion above the retainer after a valve job, when you have a valve job done and

they butt grind the valve stems to adjust the

stem protrusion. Then the bucket pushes on the retainer instead of the valve stem, even with the shim in-place.

#2 I have seen people grinds shims on a bench grinder, when they aren't square they get spit out of the retaining shoulder on the retainer, like a watermelon seed...

#3 aftermarket retainers that have incorrect geometry at the keeper interface, allowing the valve w/keepers to pull throught he retainer.

#4 the valve stem groove is improperly machined and the keeper/stem/retainer fit is poor.

There are alot of causes for valve train failure, I have seen, or done, most of them...

Close examination of the mating parts will reveal the culprit.

Happy Hunting!

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