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HELP!!! Weird tapping noise.

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Old Aug 4, 2009 | 10:25 PM
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Angry HELP!!! Weird tapping noise.

I had a slight tapping in my car that was loudest around 1500-2000 rpms. The engine wouldn't tap until it got warmed up. I opened the hood and noticed it was only on the passenger side of the engine. I had some friends look at it and was told its probably a rocker arm. I pulled the valve covers and rocker arms. One of the push rods was bent just a bit. I got scorpion roller rockers with a 1.7 ratio. I also got the manley 7.4 long and 5/16th push rods. I installed everything, torqued it and reassembled all the parts. I started it and ran it for about five minutes. Nothing at all. I got in my car and left for my house about a mile away. Halfway there the notorious tap again. I opened the hood and listened to it. Now it seems to be a bit louder and just the same thing. 1500-2000 rpms is when it is the loudest. At idle it does not tap at all. When the rpms hit around 1250 the tap is there and fairly quiet. Over 2000 rpms i think the engine noise is drowning the tap out. Any ideas or thoughts of what it could be? I need to keep the price down because I am planning a wedding for Sep. 12. Please help me out!
Old Aug 5, 2009 | 06:54 AM
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OK you had a bent pushrod. How did that happen? Normally it occurs with misshift at WOT and high RPMs ie. 3rd to 2nd. If this is the case you probably bent the valve too.
Old Aug 5, 2009 | 07:21 AM
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So pull the heads and check for a bent valve? Do you have any other sudjestions as to what it could be? I was told to get some stuff called sea foam and put it in my intake and see if that fixes it. I was told that maybe it is a carbon build up on my valves and its not allowing it to close all the way. That in turn is causing my rocker arms to tap on the push rods? Possible? Worth the try?
Old Aug 5, 2009 | 07:38 AM
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Originally Posted by farva
So pull the heads and check for a bent valve? Do you have any other sudjestions as to what it could be? I was told to get some stuff called sea foam and put it in my intake and see if that fixes it. I was told that maybe it is a carbon build up on my valves and its not allowing it to close all the way. That in turn is causing my rocker arms to tap on the push rods? Possible? Worth the try?
What caused the pushrods to bend? Manual Over-Rev?
Old Aug 5, 2009 | 07:52 AM
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I have no clue what bent the push rod. The last time I even reved it above 3000 was on the highway when I race a twin turbo hoped up diesel truck that thought he had something. I was on a long road trip from Jersey back to Ft. Campbell. That was about a months ago. About a week after I was back my oil change was due. That same week it started tapping out of the blue. I hoped that when I changed my oil that it would go away. Not so much. It did seem to get quieter with the oil change but it was still there. This is a dd car so I try not to race it or beat the ***** off of it as it is my only car! I haven't changed any of the internals on the engine up until this point with the rockers and rods.

Last edited by farva; Aug 5, 2009 at 07:54 AM.
Old Aug 5, 2009 | 10:28 AM
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Is there any way you can get a sound clip? I don't even know why you have aftermarket rockers on a totally stock engine. Very high revs (miss shift) normally causes bent pushrods, do you have an M6 or A4? Could be normal valvetrain chatter, really can't tell without a sound clip.
Old Aug 5, 2009 | 08:16 PM
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you didn't reuse the rocker bolts did you. they may be torque to yield. so they are stretched and did not hold torque.
Old Aug 6, 2009 | 06:18 AM
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Originally Posted by BC2002SS
you didn't reuse the rocker bolts did you. they may be torque to yield. so they are stretched and did not hold torque.

They aren't torque to yeild.
Old Aug 6, 2009 | 06:22 AM
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Originally Posted by farva
So pull the heads and check for a bent valve? Do you have any other sudjestions as to what it could be? I was told to get some stuff called sea foam and put it in my intake and see if that fixes it. I was told that maybe it is a carbon build up on my valves and its not allowing it to close all the way. That in turn is causing my rocker arms to tap on the push rods? Possible? Worth the try?
No need to pull the head to check for a bent valve. Do a compression test on the cylinder that had the bent pushrod. If the valve is bent the compression will be very low.
Old Aug 6, 2009 | 07:46 AM
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Im going to be completely honest with you. I have no clue how to do a compression test. I will have to take it to the shop on post and ask the mechanics there to help me. Also I was wondering if it could be a lifter too? I have heard from some coworkers that it may be that. I will try to record a sound clip. The only problem is that I will have to do it off of my phone and I am not sure how good of a quality it will be. I will try to do that tonight.
Old Aug 6, 2009 | 05:11 PM
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If I were you sell the Scorpion rockers to get some $$$ back, no need for those. Stock rockers are the best out there for most applications, with upgraded bearings there is hardly any need for aftermarket. Too much weight over the valve.

I'd do a compression test, probably a bent valve.
Old Aug 6, 2009 | 05:28 PM
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How do i add a video on here?
Old Aug 6, 2009 | 07:38 PM
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Originally Posted by farva
How do i add a video on here?
Upload to a site like photobucket.com and post the link here.
Old Aug 6, 2009 | 08:02 PM
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here is the link to the video. i am going to get a compression tester tomorrow and throw it on there tomorrow evening to see what happens.
http://s926.photobucket.com/albums/a...90806-1713.flv
Old Aug 6, 2009 | 11:09 PM
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That sounds really bad. It's hard to tell, but that sounds like something in the middle of the motor. Lifter? My bent rod sounded like that as well, but it's hard to tell with the camera phone.

Pop the valvecovers and see what's up again.



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