but I would start with the lifters or bent push rod. I just did mine over the weekend and it just took about six hours with a valve spring swap.
94 - Horrible Noise [Audio]
Thread Starter
Pro
Joined: Jun 2004
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From: Mandeville, LA / Clemson, SC
94 - Horrible Noise [Audio]
Hey guys, I had this problem start this week. I was out riding around, got on it a little (no more than 1/2 throttle) then immediately after, I started hearing this clicking from my motor. I got it home and pinpointed it the best I can to right under the intake manifold. It is kind of hard to describe, so here is the audio:
The crazy part is after shutting the motor off, you can still hear some clicking like thermal expansion. I ran it w/o valve covers and when you shut the engine off and you can feel 3-4 of the pushrods "clicking" or at least vibrating with the clicks. So my question is; could this be lifters? Some other suggestions? There is no play in the pushrods/rockers. I have great consistent oil pressure so I really don't think I spun a bearing. Also, performance feels fine (based on throttle response in the driveway).
Thanks for any suggestions,
Jeff
The crazy part is after shutting the motor off, you can still hear some clicking like thermal expansion. I ran it w/o valve covers and when you shut the engine off and you can feel 3-4 of the pushrods "clicking" or at least vibrating with the clicks. So my question is; could this be lifters? Some other suggestions? There is no play in the pushrods/rockers. I have great consistent oil pressure so I really don't think I spun a bearing. Also, performance feels fine (based on throttle response in the driveway).
Thanks for any suggestions,
Jeff
Melting Slicks
Joined: Oct 2005
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From: Daleville Indiana
St. Jude Donor '08
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Pro
Joined: Jun 2004
Posts: 520
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From: Mandeville, LA / Clemson, SC
I really appreciate the reply!! I will probably do that. It is weird that 5out of 16 pushrods vibrate after shut down, not just one. If just one was doing that, I would say it is definately lifters. But, I need a place to start. How would you check for a spun bearing and could lifters make that much noise while running?
Thread Starter
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Joined: Jun 2004
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From: Mandeville, LA / Clemson, SC
Pro
Joined: Jul 2002
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From: Port Charlotte Fl
maybe it was just me, but i thought i heard a distinct rattle when you rev'd it also.
you said you have checked it with the VC's off? oil flow was good from all tappets/rockers?
definatly odd the clicking after shut down, could see how that could almost be ignored as a theramal induced noise, but after listening to it a couple of times, you can distinctly hear a thermal expansion click in the background.
not sure bro. have never heard a lifter do that AFTER shutdown, but i would definatly start leaning that way, just based on the sounds
a spun cam bearing might also cause that, but then i would think you would see that in reduce oil flow to a specific set of lifters
you said you have checked it with the VC's off? oil flow was good from all tappets/rockers?
definatly odd the clicking after shut down, could see how that could almost be ignored as a theramal induced noise, but after listening to it a couple of times, you can distinctly hear a thermal expansion click in the background.
not sure bro. have never heard a lifter do that AFTER shutdown, but i would definatly start leaning that way, just based on the sounds
a spun cam bearing might also cause that, but then i would think you would see that in reduce oil flow to a specific set of lifters
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
wow ...really strange...never heard that before!
get an account here and ask too,there are a lot of cool people too
and a lot of engine assemblers and machinists i got a lot of help there!
http://www.hotrodders.com/forum/engine/
get an account here and ask too,there are a lot of cool people too
and a lot of engine assemblers and machinists i got a lot of help there!
http://www.hotrodders.com/forum/engine/
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Thread Starter
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Joined: Jun 2004
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From: Mandeville, LA / Clemson, SC
I really appreciate the replies!!! Now that you said oiling of the rockers...are you supposed to immediately have oil flowing out of the pushrods when the car is cranked? It takes almost 1-2min for mine to start flowing. I didn't think that was normal. I guess that could mean spun bearing. Is there anything else I can check that you all know of?
Also, lifters a probably still worth a shot since, even if I have to rebuild the motor, I will need new lifters. Are the LTX lifters special? Could you suggest a set or am I better off getting ones from a parts store?
Thanks again!!!
Jeff
Also, lifters a probably still worth a shot since, even if I have to rebuild the motor, I will need new lifters. Are the LTX lifters special? Could you suggest a set or am I better off getting ones from a parts store?
Thanks again!!!
Jeff
Le Mans Master
Joined: May 2007
Posts: 8,448
Likes: 27
From: Valparaiso
Yes
Oil its supposed to flow inmediatly,i think
Check your oil pressure sensor,its located on top of the block
Oil has to reach there to make it work
So i suppose that your oil pressure its OK and it does not comes down when warm ????
Oil its supposed to flow inmediatly,i think
Check your oil pressure sensor,its located on top of the block
Oil has to reach there to make it work
So i suppose that your oil pressure its OK and it does not comes down when warm ????
Pro
Joined: Jul 2002
Posts: 524
Likes: 1
From: Port Charlotte Fl
certianly with in seconds (3 -5 at best i would guess), if its taking 1+ minute that would explain the heavy ticking, and the bearing rattle i hear when you rev'd it. The clicking aftrwards... lifter bleeding down??
i would say minimum new cam bearings ( only way to know is pull the cam look at the oil holes on the bearings, they should all be uniform in location) i would say look for one that is noticably out of line. course as soon as you pull the cam you will no doubt know which one is bad.
or even pulling the lifters that are "vibrating" as you say, will also no doubt give a very strong indication as well.
good luck Bro, and keep us all here posted as ya go, lots of knowledge and help on here
i would say minimum new cam bearings ( only way to know is pull the cam look at the oil holes on the bearings, they should all be uniform in location) i would say look for one that is noticably out of line. course as soon as you pull the cam you will no doubt know which one is bad.
or even pulling the lifters that are "vibrating" as you say, will also no doubt give a very strong indication as well.
good luck Bro, and keep us all here posted as ya go, lots of knowledge and help on here
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
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From: Mandeville, LA / Clemson, SC
Thanks for the posts!! I will start pulling some stuff back off this weekend. I'll post some pictures if I see something interesting and definitely keep you all posted. Thanks again for all the advice!!
On a side note (small detour!!) our school purchased a high speed camera and I took some video of the valve train while running. I thought it was pretty cool:
It was shot at 60fps, it will go up to 1200fps but the quality is not nearly as good. I thought you all would enjoy it. Also, the music is a good friend and me.
Thanks again!!
Jeff
On a side note (small detour!!) our school purchased a high speed camera and I took some video of the valve train while running. I thought it was pretty cool:
It was shot at 60fps, it will go up to 1200fps but the quality is not nearly as good. I thought you all would enjoy it. Also, the music is a good friend and me.
Thanks again!!
Jeff
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
Likes: 2
From: Mandeville, LA / Clemson, SC
Thanks!!! I was hoping not to have to rebuild the motor unitl I was out of grad school!!! We'll see.
I'm going to go ahead and buy some lifters and give that a try, providing everything looks ok coming out. Could I get some suggestions on which ones to buy? Are the ones from the parts stores ok??
Thanks,
Jeff
I'm going to go ahead and buy some lifters and give that a try, providing everything looks ok coming out. Could I get some suggestions on which ones to buy? Are the ones from the parts stores ok??
Thanks,
Jeff
Safety Car
Joined: Feb 2000
Posts: 3,771
Likes: 0
From: MANDEVILLE, LA La
Thanks!!! I was hoping not to have to rebuild the motor unitl I was out of grad school!!! We'll see.
I'm going to go ahead and buy some lifters and give that a try, providing everything looks ok coming out. Could I get some suggestions on which ones to buy? Are the ones from the parts stores ok??
Thanks,
Jeff
I'm going to go ahead and buy some lifters and give that a try, providing everything looks ok coming out. Could I get some suggestions on which ones to buy? Are the ones from the parts stores ok??
Thanks,
Jeff
I have a good set Jeff at the house.
Call Me
Big D
Racer
Joined: Jun 2006
Posts: 408
Likes: 0
From: Elkton MD
"Valve" noise
I've heard that noise three times (running noise, not the thermal clicks after shut down).
Once was a bent push rod that had slipped out from under the rocker arm. Big dents in the rocker cover made the problem obvious.
Once was a cracked inner valve spring (Olds 425 ci). The cracked valve spring was hardest to find. We could have used a mechanics stethoscope if we'd had the sense.
The time that sounded most like yours was a cracked splice plate (the dish that connects the crank to the torque converter). We never would have found it but a neighbor saw us puzzling over it at told us right away what it was.
Hope this helps.
PS, nope it was 4 times. A neighbor had a '65 big block 4 speed stick with only a few thousand miles. He really ran it hard. The pilot bearing in the back of the crank had gone.
Once was a bent push rod that had slipped out from under the rocker arm. Big dents in the rocker cover made the problem obvious.
Once was a cracked inner valve spring (Olds 425 ci). The cracked valve spring was hardest to find. We could have used a mechanics stethoscope if we'd had the sense.
The time that sounded most like yours was a cracked splice plate (the dish that connects the crank to the torque converter). We never would have found it but a neighbor saw us puzzling over it at told us right away what it was.
Hope this helps.
PS, nope it was 4 times. A neighbor had a '65 big block 4 speed stick with only a few thousand miles. He really ran it hard. The pilot bearing in the back of the crank had gone.
Last edited by IRAraid; Apr 24, 2008 at 01:09 PM.
Thread Starter
Pro
Joined: Jun 2004
Posts: 520
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From: Mandeville, LA / Clemson, SC
Well, I replaced the lifters and no go:
So, then I drained the oil and cut the filter (should have done this first):
The shavings are non-magnetic. So, I'm feeling a motor build in the near future. This is very aggravating...it was in storage for almost a year and I fixed it up and put insurance back on it and only had it 5days before this!! Thanks for the help and I would appreciate any comments or suggestions on what to do. I'm going to wait until after graduation 05/17!! and pull the motor but, I’ll probably start disassembling it a little.
Thanks for all the help and be looking for a post on a new motor build!
Jeff
So, then I drained the oil and cut the filter (should have done this first):
The shavings are non-magnetic. So, I'm feeling a motor build in the near future. This is very aggravating...it was in storage for almost a year and I fixed it up and put insurance back on it and only had it 5days before this!! Thanks for the help and I would appreciate any comments or suggestions on what to do. I'm going to wait until after graduation 05/17!! and pull the motor but, I’ll probably start disassembling it a little.
Thanks for all the help and be looking for a post on a new motor build!
Jeff
Safety Car
Joined: Feb 2000
Posts: 3,771
Likes: 0
From: MANDEVILLE, LA La
Railrod Tracks
We always have something Good & Bad going on in our Lives.
All happens for a reason.
It's going to be better in the long run. Rest assured.
Let me know if I can help with anything
D
All happens for a reason.
It's going to be better in the long run. Rest assured.
Let me know if I can help with anything
D