Valve clatter/chatter...

[vping]

I get in the am start it up until the temp gets to about 150º. After about 10 mins. of driving, my valves are making a racket but only mid range. At take off they are ok, then it's a bit noisy as I sped up a bit. During acceleration it sounds awsome up unitl I shift then it starts again.

This only happens when the engine is at normal temp.

I have the valves set at .015" hot but was thinking about changing to .013" hot.

Seeing it that is sounds fine when it is colder and not fully warm, but runs & pulls great, should I be looking at the valve clearance for a solution to the noise?

 

[ronzet]

Vping,

I assume that the oil pressure is still in the 60psi range when you are at normal operating temp???

 

[ronzet]

Vping,

I am a bit perplexed at the symptoms... If it is from the valve clearance, then the noise would be pretty constant with an increase in clatter with an increase in rpm...

The amount of clatter that you are describing a change from .015 to .013 would not be much of a difference...

It is the coming and going that has me perplexed and leaning toward an oil pressure problem. The rockers are at the top of the oil flow chain and are the most susceptible when the oil pressure is below spec. Reduced oil pressure can be caused by worn out rod and main bearings, faulty oil pump, etc...

Just waxing philosophic.....

 

[tony barnhill]

I've just advanced the timing on the '79 I bought a week or so ago....valves started chattering louder than normal...so, I redid them at .012 to quieten them down...how's your timing?

 

[vping]

Ya know I need to recheck this and keep forgetting about it. I have only set 1 or 2 times at 10 deg static. Now that it is running better I can check it with my timing light. I don't get any pinging or knocking though.

 

[vping]

[ QUOTE ]
Vping,

I assume that the oil pressure is still in the 60psi range when you are at normal operating temp???

[/ QUOTE ]

This question just dawned on me. While I am driving the oil pressure goes up & down but is between 50 & 60. When I say it goes up & down its like a clock. Tic toc, tic toc. Up down, up down. Never falls below 50 or above 60 while at speed.

Is the chatter related to timing or is something going wrong with my oil pump?

or...

Is the fluctuation in oil pressure related to the timing or is something going on with my oil pump?

 

[ronzet]

Vping,

Your oil pressure seems to be fine... 50 to 60 psi is well within tolerances.. It should go up and down as the rpms vary from idle to cruise...

Actually, my ol' driver B rarely gets above 30 psi...AND the valve clatter is not extreme as yours seems to be...

I KNOW the bearings are shot but it isn't going to get rebuilt until my A is finished...

Ya' got me... I am at a loss for an explanation... /ubbthreads/images/graemlins/rolleyes.gif

 

[jlaird]

Is the rocker shaft worn to the point that the adjustment changes all the time?

https://www.rockerarms.com/Austin.htm 106 bucks for the whole thing new.

 

[ronzet]

Jack, It seems that your suggestion may be a good one.. Hadn't thought of that. Let's see, only clatters when loaded..hummm... could be... /ubbthreads/images/graemlins/rolleyes.gif