I have been trying to figure out this engine tick, I have adjusted the valves and gave it 3/4 of a turn and I pulled the fuel pump to ensure that wasn't the issue. I'm confident its in the valve train and I'm trying to gauge the severity of the problem i.e. run it till it explodes (not really but you know what I mean), or fix it ASAP. The cam was replaced 10-15 years ago with a 'milder' than stock cam, sorry don't have more info that that on the cam. The 1st vid is cold and the 2nd is with the engine warm. Thanks in advance for all constructive opinions and help.

http://www.youtube.com/watch?v=JlirV...ature=youtu.be

http://www.youtube.com/watch?v=gUnkT...ature=youtu.be

 

Could you be hearing it from an exhaust manifold leak.
Mine got real loud when I blew a drivers side down pipe doughnut.
Marshal

 

your videos are private and cannot be viewed. I agree with a possible exhaust leak. You are sure you have no wear in the rocker arm studs or arms?

 

The videos should be viewable now, let me know if not. I just replaced both doughnuts and heat riser gasket when doing some exhaust work. I did spot check a couple studs while doing the valve lash but did not look at all of them. That might be worthwhile.

 

they are viewable now. Take a short piece of rubber hose and use it like a stethoscope to determine if the noise is actually coming from the valve covers. What oil are you using on this engine? Are you adjusting the valves running or cold? If cold what method are you using?

 

I adjust them cold.When I adjust the valves I set the engine at TDC then I have a list of valves that are adjustable at that setting, I adjust them and mark the rocker arm with soap stone when done so I know its completed. Then I turn 1 revolution so #6 is at TDC and do the same thing. When I adjust the valves I back off on the nut and then grab the pushrod between 2 fingers and twist it as I slowly tighten down on the nut, once it stops spinning easily I turn the nut 3/4 of a turn.
I have narrowed it down to the rockers covers, I use a long screwdriver set against the cover bolts and the other end on my temple and it is definitely coming from the valves. I am pretty sure the noise is coming from the drivers side as it is quite a bit louder on that side.
Running Valvoline High Mileage oil 10W-40.

 

I don't see how it would be possible to adjust them the way you describe it?
Here's how I do it:

Intake Valve Adjustment:
with #1 cylinder Intake Valve at full valve lift .... Adjust #6 Intake Valve
with #8 cylinder Intake Valve at full valve lift .... Adjust #5 Intake Valve
with #4 cylinder Intake Valve at full valve lift .... Adjust #7 Intake Valve
with #3 cylinder Intake Valve at full valve lift .... Adjust #2 Intake Valve
with #6 cylinder Intake Valve at full valve lift .... Adjust #1 Intake Valve
with #5 cylinder Intake Valve at full valve lift .... Adjust #8 Intake Valve
with #7 cylinder Intake Valve at full valve lift .... Adjust #4 Intake Valve
with #2 cylinder Intake Valve at full valve lift .... Adjust #3 Intake Valve


Exhaust Valve Adjustment

You will notice that this is the same procedure and sequence as the intake valves listed above. Only now you are adjusting ONLY the exhaust valves the same way.
with #1 cylinder Exhaust Valve at full valve lift .... Adjust #6 Exhaust Valve
with #8 cylinder Exhaust Valve at full valve lift .... Adjust #5 Exhaust Valve
with #4 cylinder Exhaust Valve at full valve lift .... Adjust #7 Exhaust Valve
with #3 cylinder Exhaust Valve at full valve lift .... Adjust #2 Exhaust Valve
with #6 cylinder Exhaust Valve at full valve lift .... Adjust #1 Exhaust Valve
with #5 cylinder Exhaust Valve at full valve lift .... Adjust #8 Exhaust Valve
with #7 cylinder Exhaust Valve at full valve lift .... Adjust #4 Exhaust Valve
with #2 cylinder Exhaust Valve at full valve lift .... Adjust #3 Exhaust Valve

 

Sounds like an exhaust leak. I would start with a vacuum gauge. They are inexpensive to purchase and easy to use. There are a few good videos on how to read on You Tube. The gauge will give you the best indication of the health of the valve train without tearing down the engine. Good luck. Jerry

 

On the first video (cold) when you hit the throttle twice the noise under acceleration from one valve is louder than at idle so I would suspect that it is either an exhaust manifold leak or a bad valve. Look for a leak and use a vacuum gauge to check for fluctuations.

 

Cool thanks guys, I'll head down this road and see where it takes me! I'll update what I find.

 

The more I listen to it the more I lean towards it being an exhaust leak, maybe I'm trying to be optimistic? But I did throw a vacuum gauge on there and made some videos. I did one before adjusting the carb a bit and one after. From the research I have done online about vacuum diagnosis I would lean towards bad valve guides or a weak cylinder from the results. Thoughts?

Before Carb Adj

After Carb Adj

The tach/dwell meter is set to RPM during the videos. I know its hard to see in the videos but the red/green transition on the vacuum gauge is about 18-19 inHG

 

Have you checked to see if you have a broken valve spring.

 

I have not, would it be obvious?

 

Have you looked at vacuum gauge engine diagnostics .A waving needle indicates valve issues ,valve guide leaks, weak springs and no it would not be obvious apart from running a little rough.

 

First a disclaimer---no expert here...but when I had a broken valve spring, it was very obvious...would hardly idle. The vac gauge does seem to move a little erratic so maybe something going on there. I finally chased a ticking sound down in mine to different sized pushrod guides--was a pretty cheap repair. Good luck.

 

I think you have over tightened the valves so they are not closing all the way(some of them anyway) Did this problem just slowly develop or was it right after the valve adjustment or other work?

 

After chasing engine noises for 30 years - that sounds like exhaust to me. Could be the audio quality, but sounds like exhaust. There are several tricky little places leaks can hide and drive you crazy. Could need new manifold to head gaskets, new donuts, heat riser gasket or butteefly bushing, could be a Crack on back side. Engine looks pretty patina - so I would change all of these. Could use a new air filter while you're at it.

 

With an older engine I set the valves with the engine running .I only bring them down about half to three quarter turn .sure sounds like valves are out of adjustment.you .can get clips to put on rockers to controll oil splatter or cut out an old valve cover.
Wes


Clips for setting valves when running




Small block valve cover cut out to set valves

 

I know its been a while but my time was being used other places, I got around to installing a gasket on the drivers manifold (did not have one when I took it apart), the noise is still there and I will tackle the passenger side sometime soon when it warms up a bit more. The donut gaskets and heat riser gaskets were replaced about 6-8 months ago.

www.youtube.com/watch?v=TqGE-cUDtVw

 

look at maybe the fuel pump rod that drives it from the cam, my 68 427 made a lifter noise and it turned out to be fuel pump related, just another idea,,,