Rocker noise, grrrrrrr!
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Rocker noise, grrrrrrr!
Ever since ive gotten my 86 4runner it has had some rocker noise. I replaced the headgasket on it about 2 weeks ago. We adjusted the valves then & it still had rocker noise. Well tonight at work i went through and checked them. I had to re-adjust 3 out of 8. I put the cover back on and now it seems to be louder. It wasnt as loud before the adjustment. And it seems to be it the back and i didnt even adjust those. This is driving me nuts! A friend of mine has a 89 yota with pretty much the same milage, 200,000. You can barely hear his, but mine is just so much louder. You can hear it inside the vehicle. It runs great i will emit that but the noise, grrr. I ran the vehicle to running temp and done the intake at .008 and the exhaust to .012. This is really annoying me. I feel they are way to loud, and it seems to be in the back part of the head. Any idea's for this? Can i adjust them a little tighter? Any help with this will be apperciated. Thanks.....
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when using the feeler gauge, it must fit quite snug. redo the job. make sure the engine is good and hot. it is supposed to make a slight noise.
before removing the valve cover, use a stethoscope, or long screwdriver, or stick. use it up to your ear and try and determine what valves are loudest.
before removing the valve cover, use a stethoscope, or long screwdriver, or stick. use it up to your ear and try and determine what valves are loudest.
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I had real good drag on the feeler gauge. And the engine was at normal operating temp. And after listening with my stethoscope, it is at the back of the head. I pulled the cover off again and double checked. They are all good. Are some sometimes louder than others? Its just to loud to me. Can i adjust them to a little tighter tolerance or will this cause me problems?
#5
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This is taken from another thread. Some things to look at.
>>>*The rocker arm assembly on these engines has several places that can cause noise. The obvious is the pad, note that often we will see a small groove develop on the inner side of the pad. This is caused by the lobe shape at peak lift. If not excessive, the pad can simply be refaced and the arm returned to service.
The end of the adjuster screws move back and forth across the valve tip and over time an hourglass shape will develop. Then attempting to adjust the lash relocates that shape and we then have noisy operation. Plus we can see fractures develop in the end of the screw from loading, if allowed to continue we see damage to the valve tippet.
One overlooked point is the threads in the arm, over many thousands of miles the valve side of those screw holes can loosen. Then we can see the screw itself break right at the lockdown nut seat from side loading. Run the screw in halfway from the bottom side and try to work it back and forth, if you can, replace the arm. We use a small wire brush on the end of a drill, a couple of strokes cleans the threads and this is helpful for installation. Never try to tap those threads, it doesn't work.
Another source of noise is the bottom side of the rocker shaft itself, it is common to see a lot of wear there. If present, accurate adjustment is impossible, the shafts will need to be replaced.
Some of these engines have so many miles on them we are now seeing a few rocker arms with the shaft housing bore worn, just a few years ago this almost never happened. This is easy to check for, slide the arm on a known sound shaft and try to rock it, some motion is acceptable of course but if very loose, replacement of the arm is the only solution.
We bite the bullet and buy Toyota only when arm replacement is required, otherwise we just recondition them and put them back on. A good used or reconditioned arm is just as good as a new one....*EB
The end of the adjuster screws move back and forth across the valve tip and over time an hourglass shape will develop. Then attempting to adjust the lash relocates that shape and we then have noisy operation. Plus we can see fractures develop in the end of the screw from loading, if allowed to continue we see damage to the valve tippet.
One overlooked point is the threads in the arm, over many thousands of miles the valve side of those screw holes can loosen. Then we can see the screw itself break right at the lockdown nut seat from side loading. Run the screw in halfway from the bottom side and try to work it back and forth, if you can, replace the arm. We use a small wire brush on the end of a drill, a couple of strokes cleans the threads and this is helpful for installation. Never try to tap those threads, it doesn't work.
Another source of noise is the bottom side of the rocker shaft itself, it is common to see a lot of wear there. If present, accurate adjustment is impossible, the shafts will need to be replaced.
Some of these engines have so many miles on them we are now seeing a few rocker arms with the shaft housing bore worn, just a few years ago this almost never happened. This is easy to check for, slide the arm on a known sound shaft and try to rock it, some motion is acceptable of course but if very loose, replacement of the arm is the only solution.
We bite the bullet and buy Toyota only when arm replacement is required, otherwise we just recondition them and put them back on. A good used or reconditioned arm is just as good as a new one....*EB
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The timing chain is new. After reading what you put (thook) im going to check these things. Im going to pull the cover off tonight at work and see if i can find anything. I have a extra fully assembled head. Im about to see about swapping rocker assemblys to see what happens. "Learning something new everyday" Thanks....
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