Hello everyone,
So heading out for one of the final rides of the season before I put her away for the winter she developed this tinging or pinging noise that increases and decreases with idle speed. The noise developed while driving and continued all the way back home. I have attached a video from Youtube. The car didnt appear to lose any power under throttle but needless to say I got it home and shut her down. It sounds like it may be coming from the back of the motor or from the carb area. I popped off the oil cap and it did not sound like it was coming from the crankcase. The video is on cold start up the next day. I have not started taking anything apart yet, I wanted to get this out on the forum to gather some starting points! Thanks in advance.

Andy F.


The car has:
470cid 455 BB
Edelbrock heads
Comp Cams, Magnum Rockers
Torker Intake
Holly 770 Carb
Hooker Headers
Dynomax exhaust
MSD Ingnition (6AL-2)
Aeromotive fuel delivery
Richmond gears 3.42

 

Exhaust gasket leak

 

 

I agree ^^^, Take the belts off then start it up.

 

Thanks guys, Ill start taking the belts off. On a side note the headers on this car were installed by the previous owner.. in your opinions if the header developed a small hole would that produce a tinging sound like this one?

 

Absolutely a hole would do it.
Could be lose header bolt(s)- check for tight prior to pulling belts
Would leak more when cold / the heat expands and seals
Header gasket ?

 

Very good I will try both.

 

x3 on it sounds like contact. If the headers check out and removing the belts doesn't change anything have a look at the Torque convertor bolts - assuming the car is an automatic.
I've seen those come loose before and make a similar noise. - Jeff

 

What it sounds like to me is the water pump impeller hitting the timing chain cover.

 

The only time I ever had that happen was back when I was a poor school boy and didn't run antifreeze - the stamped steel impeller rusted right off the water pump shaft!

 

Yeah, but I still want to see what it looks like with the pump off...

 

Thanks so far everyone, I will be taking a look at all of these suggestions. Cranking out the OT at work the past few days so Im hoping to get in the hood soon. Ill keep everyone posted!

 

Could be a loose rocker arm.

Use a stethoscope to pinpoint it.

 

Sounds like valvetrain to me. It's way to consistent with engine speed to be anything belt driven, ie waterpump. Way to metalic for an exhaust leak. I'd pull valve covers and start there. Let us know.

 

Possibly a torque converter bolt that has backed out?

 

Update: I got out in the garage today and wanted to started checking a few of the things off on this list. I started with the valve-train first and did my best to locate it with the screwdriver trick.. It seemed hard to pin point and I could not specify but it sounded like the Left head. I pulled off the cover to take a look... There are 3 rocker arms that appear to be loose.. Is ANY play in the rocker arm or push rod acceptable? On these 3 rockers I can wiggle them slightly and turn the push rod with my fingers. Im am looking for zero lash correct? I guess the bigger issue.. Is more than one arm is going loose simultaneously a warning of bigger problems?

I will be checking off the other things on this list as I go forward and again thank you everyone so far.




Andy.

 

With all of the tension off of the rocker (lifter resting on base circle), you should just be able to rotate the pushrod with your fingers. If it spins easily, it is too loose. It is not uncommon to have a locknut come loose if it wasn't tightened up correctly.

 

Update after a long New England winters nap!
The car fired right up with no issues, seemed to idle good and the sound was gone. I was pumped up and ready for a drive.. but after about a minute or two the tapping sound returned. So I returned to this thread and started wrenching. Starting with the belts.. I removed the accessory belts and the noise persisted so I scratched that off the list. Next I moved to the Tourque converter bolts and since they appeared to be in tact to the best of my knowledge I moved on. I tried (again) to listen for valve train noises using a long screw driver ( God my ears just suck for this). But there it was on cylinder number 5.. the complete opposite side I found the 3 loose arms prior to winter storage. None the less I have a rocker arm that is not even moving while the engine is running and there is obviously a ton of up and down play in the pushrod. Like the picture shows above these rockers have poly locks on them and they appear to be tight.. like almost too tight to have this much play in the arm. Is my mind going down the right path thinking that I possibly have a collapsed lifter on number 5? If that is the case in some of your opinions, I will not be tackling that myself and I will send it off to my mechanic. I just want/need to drive! Thanks again for your suggestions and thanks in advance for any input going forward.

 

I have an appointment for her on Thursday with the mechanic. Ill post the final diagnosis when I get it!

 

Sounds like a collapsed lifter or a wiped out cam lobe.

 

Crossing my fingers on just the lifter . The whole valvetrain is not that old, it was all replaced w/ comp cams within the last couple years. I do run ZDDP on every oil change so really hope its just a lifter.

 

So the sound in the video is a destroyed cam and lifters. I will be pricing out options now, this is definitely not what I wanted to hear but had a feeling it was going to be. Thanks for all the input everyone.. Ill just need to take this one on the chin and try to get her back on the road ASAP.

 

Maybe something not quite as aggressive or a roller might be a consideration. Any idea what your spring pressures are?

 

I don’t know what the springs were set as but in the words of my mechanic “they were rediculous”. Those modifications were done prior to my purchase. But Those are definitely considerations going forward. This is very depressing..