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Discussion Starter · #1 ·
I have read about several peoples problems with this and my experience is same song second verse.

I let the car (72) sit for a few hours and then adjusted the valves (.20mm in / .25 out). I then started up the car to the sound of the imfamous ticking valve. I give it a test spin and power seems better. After the car is warmed up I pull the valve cover and check the clearences, this time (.25mm in / .30 out). Everything is still good and there is a fresh coat of oil on everything indicating (I think) that the oiler is working. I get to thinking about what another guy wrote about all of his clearences being very tight. Mine were also, as a matter of fact it seemed as if there was no clearence between the cam lobe and the lifter. I had to make some pretty drastic adjustments to get these clearences back in form. then I looked at the lifter and pushed it down with a my finger. It made a tick noise when the lifter arm struck the top of the valve.

Here is what I am wondering and keep in mind I am still pretty in-experienced in all of this. Could it be that perhaps the lifter arm has slightly bent or the contact point between the lifter and the valve has eroded causing the lifter to slap down onto the valve making this clicking noise. Perhaps a mechanic in the past tightened the arm al the way to the cam to eliminate the gap between the arm and the valve thus messing up the clearences but eliminating the tick? It just seems that all my arms never stopped contact with the lobe all the way around.

Does this make sense to anybody or have I been smelling exhaust fumes to late into the night???
 

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Don't get offended here but something in your explanation got me to thinking. First off you must make the clearance adjustments/measurements between the round back part of the cam lobe, not on the high side, so each time you adjust you need to make sure the cam lobes that you are adjusting are NOT on the actuating surface of the cam lobe. If you are doing this fine, but I have heard of this before when someone just goes in and starts adjusting ALL the cam followers regardless of position of the cam. Here is an easy way to adjust from the ZX Haynes manual.....First number in your head each ROCKER / CAM LOBE from front to rear #1 through #12..With the #1 cam lobe pointing straight up, adjust #'s 1,3,7,8,9,11 rockers/valve. Now rotate the engine until the #1 cam lobe is pointing straight down... and adjust #'s 2,4,5,6,10,12.
If you are doing the adjustment properly and you are worried that it was too tight before, just keep checking every few hundred miles. It could be that your valve seats are receding and allowing the clearances to tighten up. If that is the case you will likely eventually need to have valve seats replaced. Don't get too worried about a little ticking when cold, even new mine had a bit more tick than I thought it should have. Might make sure your oil gallery tube is clean and firmly attached also. Heard about some that plugged #5 and/or 6 area or came loose toward the rear and starved the rear valve rockers causing some early start ticking.
 

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I had a compression problem and found one valve was too tight so I adjusted them all to factory spec. The valve noise is now definately worse than I'd like. But I think that's just the way it's designed. You might want to try tightening it up a couple thousandths to see what happens but no more than that. I'll be playing with mine after I get my head back with a new cam...
SoM
 

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Discussion Starter · #4 ·
yea I did everything exactly as it reads in the haynes manual. As far as the ticking it isn't just doing it when cold it is doing it all the time. And it is rather loud.

Forgive my ignorance when asking this question but is there supposed to be a clearence between the end of the rocker arm and the top of the valve itself? this is what seems to be making the noise.

Thanks
 

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What are you setting them at?? If stone cole set them at intake 8k and 10k for the exhaust and if at driving temp , drive at least 5 miles to properly warm the engine set at 10k for the intake and 12k for the exhaust maeasured as was explained above . Off the base or lowest part of the lobe NOT of the lobe. There is this clearence that allows the valve to close properly otherwise the valve if too tight will burn and then you will need a valve job , these sort of like little kids when you can hear them you know there allright its when they are vary slient that you become concerned . Adjust cold untill you have experience because if it takes along time by the time you get finished the engine has cooled and the settings are varied because of that . Gary Portland ore.
 
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