ZR550F Engine trouble, noises and proper cam timin

Motor Head wrote: If by raised valve bucket, you mean one is sitting up higher, with no valve clearance. then I'd say a shim has come loose. Yours are shim under bucket, so the shim sits on top of the valve stem.

I can not envision any scenario in which that could happen (probably because of impairment due to meds), so could you tell me how you think such a thing could happen?


As for the OP, you determined one bucket was higher than the others before removing the cams? That don't seem right either. Assuming it's an exhaust valve, that's still a max clearance of .008" or less, and that's difficult to see.

I've probably just missed something.

Only other thing I could see is a dropped valve, but then it would run on three cylinders and not for long as the piston would soon be in the cases.

I removed the camshafts and took the video before I posted the first post. It takes time to edit and upload the video hence the delay.
After taking the camshafts off I was able to see that the 3rd cylinder intake valve bucket was higher than the others. Which doesn't seem right as all the other buckets look relatively the same...i.e it was a noticeable difference as you can see from the video.

I just played your first video. Wow, I think what you are hearing is a valve contacting piston dome. Don't think it dropped the valve yet, thats a lot louder sound. If you can't remove the spark plug from that cylinder, then there is a good chance it did drop a valve.

I saved a few dropped valves, and holed pistons that I pulled out of motors that customers brought into the shop. You will never forget the sound of a valve head rattling around in the combustion chamber!!!!! Four valve motors do seem to run longer with a dropped valve than a two valve motor does. I have pulled parts of a piston with the word "ART" on them out of the end of a unbaffled KZ1000 Kerker many a time back in the day. Done blowed up real good!!!!

Looking down the spark plug hole with a pen light will show any dropped valve contact. Hopefully it is not a dropped valve, as that will be carnage.

I removed the bucket and it was the shim as you said. Its shifted out of place because of the split keeper. One of the split keepers' sides has risen out of its position and pushed the shim out of place. Is there anyway of installing the split keeper without removing the engine block I haven't checked for a dropped valve, however judging from the upper part of the valve assembly it seems ok. I'll take off the spark plug later on and check for damage to the piston, and do the leak test. I was thinking about the leak test... can I just rotate the engine and see if I get compression out of that cylinder ? I don't own an air compressor.

You need to pull your spark plug out next. Look at it for damage, as Dr GAMMA said. Hopefully its OK. If you had a keeper come loose, you need to know why. You had originally pulled the head to do a head gasket right? No valve work, or new stem seals? Did you have any of the valves out?
Did you push down on the valve to see if the spring broke? You need to find out what failed. If the spring broke, or the spring is weak, then the valve can Float at higher RPM, which will cause the shim and keeper to be able to come loose. The groove/s in the valve stem can become worn, as well as the keepers. All will need inspecting, probably replacement. You will end up pulling the head again, for the repairs.
Tuning the motor now, with the cams out, can only be done by hand. So a compression check will be not possible. You would have to re-assemble the cams back in proper time, after getting the valve keepers and the shim back in place. Not going to be easy to do. A leak down test would be quick and easy, but you do need a compressor. Do you have a portable Air Tank? Can you buy, borrow, or make one? Then you can fill the air tank up at a petrol station, and then use it as an compressed air source.

Right, just pulled out the head....no damage to the piston and the valve seems good. No scratches or anything. Anyone know how to go about disassembling one of these? Anything I should know? Also I don't really have special tools... just the basics.

In the manual it says to use a tool I don't have, anyway of going around this

Have a look at this home made spring compressor.
www.kzrider.com/forum/11-projects/408490...t=20&start=40#559767

ggvalchev wrote: Right, just pulled out the head....no damage to the piston and the valve seems good. No scratches or anything. Anyone know how to go about disassembling one of these? Anything I should know? Also I don't really have special tools... just the basics.

In the manual it says to use a tool I don't have, anyway of going around this

I made a spring compressor with a big C-Clamp and O2 Sensor from Harbor Freight, cost $9. Also a magnet is helpful for removing the keepers once the spring is compressed.

ggvalchev wrote: I removed the bucket and it was the shim as you said. Its shifted out of place because of the split keeper. One of the split keepers' sides has risen out of its position and pushed the shim out of place.

That's a scenario that didn't occur to me :laugh:

Thanks for getting back to us with your discovery, I wish more people would.

just lay the head on something flat and use a large socket and hammer, put open part of socket over valve and hit with hammer. and it will knock out the keepers.