What shall I do to this noisy valves that I have on my 4AF engine. I hear the noise sound to the far left of my valve cover directly on my #1 plug. Is it just dirty or is there something else. Car runs good but the sound is bad and annoying. Can some valve cleaners do the job? It started when I took my car to a mechanic for head gasket replacement.
since the head was just taken off, get the sparkplug out, get the piston all the way down and look through the hole with a flashlite, look for fresh dings in the piston or carbon cakes near the edges that have been flattened by the quench part of the combustion chamber in the head
Check the valve adjustment, sounds like its out of spec. No the 4A-F didnt have hydraulic lifters. 4A-F has the combustion chamber built into the piston, the piston isnt flat topped.
only part of the chamber is in the piston, its just a dished out place in the top, I put a headgasket on a 4af once and a hunk of carbon got in the quench area on the piston and it sounded like i left a bolt in the cylinder I put a long screwdriver through the plug hole and broke it up
The intake cam gear has a backlash gear that's held to the gear with a clip. There's also a threaded part that's used to hold those two parts together. Well, if you don't put a bolt in there to hold 'em together, the backlash gear will snap to a different position. That backlash gear is what has the dimple in it to align the timing marks whe installing the cams.
You can take off your valve cover, rotate the crank pulley (removing the spark plugs makes it easier) so the dimples align. Look for the threaded hole in the intake cam gear and make sure you can see through it.
hey tek, i bet your onto something, but i wonder why it would be loose, then it would sound like a 2.5 genuine GM junk with a roller cam at idle, but as the motor goes up in rpm, the cam doesnt have enough time to snap back against the gear teeth and the noise goes away
the hole is dead center and the teeth of both halves of the gear look straight accross, i wonder if the spring thingie on the2 piece gear is broke or not there, is the gear mesh between both cam gears real sloppy? OK this noise your hearing, is it real fast like gear clatter or is it kinda like a fast watch tick at idle?
No, what I'm getting at is...if the cams aren't timed right, the cams will be retarded substantially...I'm not sure what causes the noise, but it's awful. I used to have a recording of it somewhere...
so how do you move this backlash gear back into place? can you explain again,
cause when i removed my cam i didnt put that bolt there to hold it,maybe thats the damn problem to that clicking noise i have.....eh?
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I put a headgasket on a 4af once and a hunk of carbon got in the quench area on the piston and it sounded like i left a bolt in the cylinder 
I put a long screwdriver through the plug hole and broke it up 
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