I've got an auto. So that's really not the case.

I got a chance to put the pushrods on the kitchen counter and roll them around, there were three of them that didn't roll constantly -- showing evidence of being slightly bent. Not hardly noticeable if you just hold it up and look at it though. I'm hoping that this was the culprit.

With the new pushrods and adjusting the valves -- the chirping is gone. However it is definately running rough, so I'm going to have to go back and readjust the rockers again. I followed ShBox's writeup, so I'm really not too sure what I did wrong.

Basically I put a breaker bar on the crank pulley and turned it clockwise while watching the rockers. When the pushrod went all the way down (assuming the valve is closed) I tightened the rocker nut while spinning the pushrod. As soon as the pushrod stopped spinning. I turned the nut another 1/2 turn and held it tight while I tightened the poly lock (fairly hard).

There is an intermittent tick (doesn't go at any sort of rhythm like the chirp did) that I personally feel is more related to the valves not being adjusted correctly than the previous problem.

I took vid of it right after I cranked it up -- input on whether you think it sounds too tight or too loose? I know that's hard to tell on a lower quality video, but any other input would be appreciated. Thanks again for the help thus far guys, I really appreciate it.

 

it is a lot easier and more accurate to adjust them with engine running. i just ripped the flap off a cardboard box and lined the bottom of the head to keep the oil in

yea they are deffinately still a little loose

 

Got everything re-adjusted and started it up -- and its still chirping. The rockers are not making anymore noise (like they were before), but the noise is still there. Looks like I'm going to have to test the compression.

Any easy way to know if its the lifters? Any other ideas for things to check?

 

do you have an automotive stethascope?

 

No I don't. Perhaps I'll look into one tomorrow when I get the compression tester.

 

Parking in the grass can help when trying to locate engine noise. Fewer echos. And you could always use the hose-in-ear technique if you don't have a stethoscope. Funnel/cup on ear end works even better.

Be sure to tape it to your head really well.
















The tape doesn't help a bit but the neighbors love it. (Sorry bout that . Hose tip is sincere, though.)

 

could be a header gasket leaking , with the pressure of the backfire and the sound its making , id check that first. im no expert but a blown header gasket makes a chirping type sound also.

 

If it's exhaust, then do another Seafoam treatment... if it's leaking from the header gasket then you'll see it.

 

I pulled off both headers and checked the gaskets, they look old(er), but definately not blown.

I noticed the passenger side header had 4 of the 6 bolts extremely loose when I was taking it off to check the gasket, when I retorqued them down when I put it back together.

The chirp still remains

I didn't get a chance to get a compression tester, but I'm going to do that the day after christmas (hoping for a sale). I'll probably pick up a stethascope as well.

At this point, I am sincerely stumped. I can't really think of what it can be now. Is there still a possibility it could be a lifter or broken/burnt valve? The car still idles and runs fine, it just chirps. I'm running it off of the battery (no serpentine belt, alternator removed) and the chirp still remains.

Thanks again for all of the input guys, I don't know where I'd even begin without the direction. I wish you all a very happy holiday

 

Update:

I just got a chance to scope the motor. The chirping is definately coming from the passenger side head. It is most definately valvetrain. I will be doing a compression test to basically determine whether it is lifters or valves. Either way, it doesn't seem this is turning out as simply as I had hoped.

Any other suggestions please share. I'll keep you guys posted.

 

With the compression test that I did today, I really didn't find anything too conclusive. The numbers seemed within normal tolerances throughout the cylinders.

After the results of the compression test -- I'm leaning more towards a lifter being the issue and not a valve.

After doing some searching, a lot of people say that the Comp OE Replacement Lifters are more than apt to get the job done. I was considering forking the money over for some Morels, but with only the hot cam and springs I have a hard time justifying it.

Just to double check, the 850's are the Comp OE Replacements correct?
http://store.summitracing.com/partde...5&autoview=sku

Also -- I know I'll need an intake manifold gasket set. Is there anything else I need to know before tackling the install? Does anyone know of a writeup on it?

One last thing -- is this Comp Hydraulic Lifter Install Kit suggested as part of the install?
http://store.summitracing.com/partde...rt=CCA-08-1000

 

I had a chirping sound in my Nova last summer that ended up being a cracked flexplate.

 

I hope you don't have what I had. My 1995 Z28 had a chirping noise that took a lot of time to correctly figure out. I got my answer running the engine with the valve cover off with oil clips holding back spray.I put a stethescope on the rocker studs. The chirping was on cylinder #6. I loosened the adjustment until the cylinder had no more lift,then it got quiet. Tightening it just a little brought back the chirping.Tearing it down for a cam change,I found a bad stock cam lobe and a flat roller lifter. The cam lobe had a groove about 1/64" across the nose.

 

Edman, what happened first? This the lifter take out the lobe or did the lobe take out the lifter?

WhyHelloOfficer, did you get a confirmation on that part number? I'm curious too.

 

I bought the car with 88k miles on it. It sounded typical and ran very strong. But, by the second week I noticed a very faint chirping that came and went,f or short moments at a time.After about 4k worth of driving, it developed a head gasket leak.The engine was all stock and original except for exhaust ,K&N,and a 52mm TB.The head builder deemed the stock valve springs too weak to reuse, so I got Isky springs. After the install, I drove it one day for approximately forty miles when I suddenly developed an extremely loud chirping.I put about twenty more miles on the car trying to figure it out and remedy the situation.I videotaped it running with a timing light flashing onto the block.Watching my films,I noticed the chirp was half as frequent as the light flashes.That's when I knew it was strictly valvetrain.The stethescope only found the truth when it was held directly on the rocker stud of the damaged cam/lifter. I believe that the roller was going bad for quite some time, but the valve job with the Isky springs sped up the bad lifter's failure.The roller-wide groove in the lobe was cut by the flatted roller head.The roller turned freely,but the flat portion pushed around the lobe,cutting the groove over the nose due to high spring pressure.
The replacement cam is a near-stock #501.Now all my lifters make the usual LT1 clatter,maybe just a little bit more,but all equal (a little less than the video earlier).I adjusted my new lifters to 5/8 turn as I dropped them in the hole.They were all filled and pumped up ahead of time. When they were all done,that's when the intake manifold was put back on. My adventure was completely involuntary, but an education worth having.