,.....It Happened to me...Locktite them in if they backed out
valve....how does this happens
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Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
valve....how does this happens
Some good news for a change.
I pulled out the sparkplugs and took off the passenger side valve covers.
The plugs are looking pretty good, just starting to get that nice brown color. However, the end of the threads is slightly black...
The two valves on #8 are way off. They aren't even close. The poly lock nuts are still tight.
They were adjusted correctly in the first place.
So how does the valve go out of adjustment and the nut still be tight?
Both push rods are perfectly straight. Rolled them on glass.
I pulled out the sparkplugs and took off the passenger side valve covers.
The plugs are looking pretty good, just starting to get that nice brown color. However, the end of the threads is slightly black...
The two valves on #8 are way off. They aren't even close. The poly lock nuts are still tight.
They were adjusted correctly in the first place.
So how does the valve go out of adjustment and the nut still be tight?
Both push rods are perfectly straight. Rolled them on glass.
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
I'm going through it tomorrow. I'll check the studs.
Got it apart today, will adjust the valves tomorrow, and slap it back together and see how it sounds.
It looks like just #8 is out, on both valves. At first blush the rest seem OK.
Team Owner
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From: Summerland B.C. Canada
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Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Well, when the motor stopped I could wiggle the rocker with about 1/4 inch of play between the valve and the rocker tip. No way bleed down happened that fast.
I moved the motor a little by hand and got the same thing on the intake valve.
There was always a slight valve tap, but today they were loose.
I moved the motor a little by hand and got the same thing on the intake valve.
There was always a slight valve tap, but today they were loose.
Le Mans Master
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From: Myrtle Beach SC
St. Jude Donor '05-'06
Valves stuck? Did you check for compression? I remember you said you had a bang before the noise increase. Mabey the cylinder pumped gas through? Just a thought...
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
There was no audible "bang" the use of the term was more to emphasize the fact that it happened suddenly.
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Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
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Some good news for a change.
I pulled out the sparkplugs and took off the passenger side valve covers.
The plugs are looking pretty good, just starting to get that nice brown color. However, the end of the threads is slightly black...
The two valves on #8 are way off. They aren't even close. The poly lock nuts are still tight.
They were adjusted correctly in the first place.
So how does the valve go out of adjustment and the nut still be tight?
Both push rods are perfectly straight. Rolled them on glass.
I pulled out the sparkplugs and took off the passenger side valve covers.
The plugs are looking pretty good, just starting to get that nice brown color. However, the end of the threads is slightly black...
The two valves on #8 are way off. They aren't even close. The poly lock nuts are still tight.
They were adjusted correctly in the first place.
So how does the valve go out of adjustment and the nut still be tight?
Both push rods are perfectly straight. Rolled them on glass.
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Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
We'll see later. I did not throw the final adjustment on the valves. When I had the new piston installed (in an attempt to have the car running for this weekend) I asked them to check the valve adjustments and do a final adjustment. So I don't know what could have happened.
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When adjusting the valves, zero lash is sufficient to quiet valves. The 1/2 to 1 1/2 turns after zero lash is intended to put the plunger in the hydraulic lifter down .030 or more to account for wear.
I am not saying what happened to your motor, but it is true that a properly adjusted valvetrain that did not loosen the poly lock can only go out of adjustment with excessive wear or breakage. Bent pushrods and valves would fall under the breakage. Good luck either way.
I am not saying what happened to your motor, but it is true that a properly adjusted valvetrain that did not loosen the poly lock can only go out of adjustment with excessive wear or breakage. Bent pushrods and valves would fall under the breakage. Good luck either way.
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Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
When adjusting the valves, zero lash is sufficient to quiet valves. The 1/2 to 1 1/2 turns after zero lash is intended to put the plunger in the hydraulic lifter down .030 or more to account for wear.
I am not saying what happened to your motor, but it is true that a properly adjusted valvetrain that did not loosen the poly lock can only go out of adjustment with excessive wear or breakage. Bent pushrods and valves would fall under the breakage. Good luck either way.
I am not saying what happened to your motor, but it is true that a properly adjusted valvetrain that did not loosen the poly lock can only go out of adjustment with excessive wear or breakage. Bent pushrods and valves would fall under the breakage. Good luck either way.
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Another way is with the boink test.
Remove all of the rocker arms on the head you have the valve cover off of, and gently boink the tip of the valve with a small hammer. It will have a distinct feel, and sound. There is no mistaking a bent one.
.001 is enough to keep a valve from sealing. Almost nothing that goes wrong on a car is obvious. This is no exception. Unless you drive over a connecting rod, it is hard to see a hurt motor.
Last edited by Pete K; May 23, 2008 at 10:07 AM.
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
You can remove the rocker arms to let the valves close, then put air into the cylinder. If it is bent even a little bit, it will not hold air. You will hear it blowing into the intake, or out the tailpipe, depending on which valve it is.
Another way is with the boink test.
Remove all of the rocker arms on the head you have the valve cover off of, and gently boink the tip of the valve with a small hammer. It will have a distinct feel, and sound. There is no mistaking a bent one.
.001 is enough to keep a valve from sealing. Almost nothing that goes wrong on a car is obvious. This is no exception. Unless you drive over a connecting rod, it is hard to see a hurt motor.
Another way is with the boink test.
Remove all of the rocker arms on the head you have the valve cover off of, and gently boink the tip of the valve with a small hammer. It will have a distinct feel, and sound. There is no mistaking a bent one.
.001 is enough to keep a valve from sealing. Almost nothing that goes wrong on a car is obvious. This is no exception. Unless you drive over a connecting rod, it is hard to see a hurt motor.
Perhaps #8 was never adjusted right in the first place, as every thing looks OK from the top.
