tapping sound - lifters? Rockers?

[TURBOPOWERED68]

i am having a annoying tapping sound.
could it be the rockers?
When the valve is in the closed position is there suppose to be any clearance between the rocker and the valve?
i also have a few lifters that bleed out really fast, What can/should i do about this? new lifters? leave it alone?
Maybe not having any pre-load on the lifters is causing the bleed out?
Also how do i pre-load the the valves that are loose? New rockers? Longer push rods?
thanks for your help

 

[BEATAV8]

put your hand on the cam sensor. see if you can feel it coming from there.

 

[TURBOPOWERED68]

i used a stethoscope and put it all over the engine
and the noise is coming from the driver side valve cover.

 

[BEATAV8]

I think you've already identified some really good ideas. The loose ones will probably need some slightly longer pushrods. I think I would try that next. Loose rockers definitely make a lot of noise!

One of my motors is that way... One of the pushrods is a little longer than the others.

 

[mikestertwo]

Has the motor been rebuilt? Stock or aftermarket lifters? Is this problem new or has it always been like this? Need more info.

 

[TURBOPOWERED68]

bone stock and 165K miles.

 

[buttonfly]

could the cam be going flat?? Have you pulled the valve covers yet?? Maybe pull them if you dont see anything pull the intake and see what your up against.

 

[TURBOPOWERED68]

could the cam be going flat?? Have you pulled the valve covers yet?? Maybe pull them if you dont see anything pull the intake and see what your up against.

anything is possible

like a dummy when i pulled the valve covers i didn't check for anything put what i was there to do (replace the push rod and install new valve cover gaskets).
So i pull the intake, How do i check the cam? How deep the lifter sits in the bore?

 

[blue-t]

you said driver side, should check #3 cly thats the bank that is the came lobe goes not shure if its the intake or exh.

 

[TurboBuRick]

Quickest way to check the cam, pull the driver side valve cover and start the car. Watch the rockers. If one or more are not moving like the others, the cam is worn. Have a towel handy too.

What is your oil pressure?

 

[WarWagon]

While things are apart...Your close to half way for a roller cam swap.
If you just pull each lifter out and keep them sequence oriented, check for smooth lifter face with a circle polished in the middle from turning. If the lifter is anything but that it's junk.

 

[buttonfly]

Quickest way to check the cam, pull the driver side valve cover and start the car. Watch the rockers. If one or more are not moving like the others, the cam is worn. Have a towel handy too.

What is your oil pressure?

x2.........a dial indicator doesn't hurt either. #3 exh is the one prone to going flat.

 

[TURBOPOWERED68]

Quickest way to check the cam, pull the driver side valve cover and start the car. Watch the rockers. If one or more are not moving like the others, the cam is worn. Have a towel handy too.

What is your oil pressure?

i'll try this first
oil pressure is at 20 PSI HOT idle

While things are apart...Your close to half way for a roller cam swap.
If you just pull each lifter out and keep them sequence oriented, check for smooth lifter face with a circle polished in the middle from turning. If the lifter is anything but that it's junk.

i guess this would be next.

BTW i HATE taking off the Driver side valve cover i don't have much of choice.

 

[Walt Skarb]

check for an exhaust leak at exhaust header . I had an exhaust leak at header and it drove me crazy. Sounded like bad lifter or bearing.

 

[TURBOPOWERED68]

OK guys going to pull the valve cover off and check the amount of movement the pushrods have (looking for a wiped lobe/cam) while the engine is running.

So being optimistic and things are just a little worn (besides the cam) could i use Adjustable Pushrods as a crutch until the rebuild gets done?

Also if its a sticking lifter/lifters what can be done to loosen it up WITH OUT PULLING THE INTAKE off? A can of Seafoam into the oil???

the noise seems to really come on at around 2K-2300 Rpm and up.

i don't expect this engine to live much longer but i would like to at least hit the LOW LOW 12s high 11s before this racing season is over and it gets rebuild over the winter.

while i am at it i will also try to do a compression test, that should be interesting

how to i check the "preload" and what should it be?

 

[charlief1]

Isn't this your DD David? There's no quick fix for a bad cam if that's the issue here. Remember that the metal from the cam is also circulating in with the oil.

As far as a sticky lifter get some CD2 detergent and run it with fresh oil. Put a quart of tranny fluid in it and let it idle for 30 or so minutes to clean things up and then change the oil.

 

[TURBOPOWERED68]

Isn't this your DD David? There's no quick fix for a bad cam if that's the issue here. Remember that the metal from the cam is also circulating in with the oil.

As far as a sticky lifter get some CD2 detergent and run it with fresh oil. Put a quart of tranny fluid in it and let it idle for 30 or so minutes to clean things up and then change the oil.

the true DD is the wifes car.
this is my DD when i am alone in the car this one does get a lot more miles then the wifes car though.

 

[FLGN]

Any updates?

 

[TURBOPOWERED68]

Isn't this your DD David? There's no quick fix for a bad cam if that's the issue here. Remember that the metal from the cam is also circulating in with the oil.

As far as a sticky lifter get some CD2 detergent and run it with fresh oil. Put a quart of tranny fluid in it and let it idle for 30 or so minutes to clean things up and then change the oil.

Charlie
i am do for an oil change, Why wouldn't i want to do it now?

Any updates?

Yes
i managed to procrastinate a lot:redface:

 

[charlief1]

Charlie
i am do for an oil change, Why wouldn't i want to do it now?/QUOTE]

Use some tranny fluid in it because it has a high detergent content. This will help clean everything out first. 30 minutes at an idle should do it. Then do the oil change with the CD2 additive to help clean it more. If the knock doesn't go away then supect the cam is bad.