O.K. I think everyone know s the problem I ve been have with this motor,
here's the latest...

a new cam and lifters,broke in o.k. . then I went and did a final valve adjustment(hyd).
everything was nice and quiet,set the timing and went for and ride ,got on it a bit but not over 4000 rpm's and only short run,
the ride was about 2 miles and 5 minutes.
on the way back I thought I could here a ticking...sure enough when I pulled back in the garage I heard the valves clacking away....

said #@!%$^ and took a break and drank a cold one(icedtea)went out and adjusted the valves again,let it run for a few minutes and little by little I could hear the ticking come back.
all rockers have oil flowing enough to cover the ball and roller tip ,a few near the front pass side shoot out across the fender(or into your mouth when the rag blocking falls off)oil press is 50 + cold/warm and 30-35 hot @ 900 rpm's

what gives ? any Ideas?
had new cam bearing installed when rebiult,only have put 500 mior less on motor.

I'm not a big block guy so bare with me if this is a stupid reply. Are you using pressed in rocker studs that are working their way out of the head?

-dnult

:( I'm thinking like dnult that somethings coming loose as it's running. But, it didn't do this before the distributor swap? Or it did? And I have 1 more question. How long was the motor assembled before you installed & ran it?
I ask because I've seen lifters & sometimes springs start to fail if they've been in the compressed state too long.
If I know one of my motors is going to sit a long time I back off the rockers. I learned this the hard way.
Of course, there are alot of variables for that too like BIG cam, wore out motor, too stiff of a spring for the application and so on that would effect it. And then the equation of "how long it's been sitting".
I'm wondering if the lifters are shot. Are the rocker nuts staying tight?
How do the spring retainers look on the valves?
I'm just throwing things out there. :confused:

If you have stamped steel rockers and adjustment nuts that you can see the stud threads above the nuts look for ones with more threads showing. They should all be fairly even so more threads will point you to the source of the problem. More threads can indicate over tightened lifters (could keep valves from closing all the way), pressed in studs working their way loose or a lobe on the cam going away.

This can work the other way too... If after the valve adjustment the threads all look about even and after some running you get a bit of lifter clatter look for less threads showing. That would be a sign of a rocker nut coming loose.

If your are running poly locks (usually with roller rockers but stamped steel too) my money is you are not locking them down properly. This is too common and they come loose real easy. Once you have your 1/2 turn (or whatever your cam manufacture recomends) past zero lash you lightly snug the center screw down against the stud. then you tighten the outer nut and center screw against each other (equal pressure in each direction)

Anyway glad to see you back at it... Remember it's a hobby and when you hit the wall on a problem set the wrenches down and walk away for a while. Use the time to think out what the problem is and when you go back at it, it'll go easier!! graemlins/beers.gif

the motor was together for about a month before running,
the heads have screw in studs,I didn't think you
ran poly locks on hyd cams.
I'll definitly check the rockers for backing off.

[ 05-22-2003, 05:19 AM: Message edited by: fastorange67 ]

the nut are not backing off,
how fast should the push rod spin ?

also how can you tell a s/b stock rocker from a big block stock rocker(I have a set but not sure what they came from)

The pushrods should spin if the lifter is rotating like it is designed to. If there is more friction in the rocker arm pushrod seat, they might not rotate along with the lifter. The lifter needs to rotate. Are you using a set of used rockers? Big block rockers are 1.7 ratio nominaly and can be used on small blocks with a LOT of work. This is not advised at all.

I am suspecting either a valve adjustment, or possibly a loose header bolt.

-Mark.

possibly a loose header bolt ??????

Loose header bolt can cause a "ticking" sound. This has fooled me more than once on my own car. graemlins/clonk.gif
You drive around and the engine heats up and the bolts will sometimes back out a bit. Then you hear the ticking and assume it to be valvetrain related. I would verify that you do not have any exhaust leaks while you are scratching your head looking at the valve train. smile.gif

A cam lobe going flat comes to mind but I was trying to find the "happy" to fix stuff first.

-Mark.

if it's cam it would be the third one with a different lobe each time #8 intake,#8exhaust,now #7 exhaust if that's the problem.
need to get back in the mood just don't even want to look at it right now!

if it turns out to be the cam the motor will come all the way apart and start over,maybe the wife will let me get a creditcard and a 502 :D ;) tongue.gif

With this maybe being the third flat cam, is there a possible mechanical bind? Valve springs coil binding or rockers binding on studs? I am using the 781 heads and had to use rotator cups under my valve springs to get the correct heigth with comps valve springs and to also center the springs in the head. After adjusting the valves, then going for a ride and noise shortly after, something has come loose or wore. Mark

BACK AGAIN!!!!!!
I checked the headers did find a few loose but wasn't the problem!.
pulled off the rockers checked push rods for straight,and rockers for wear.none.
did find that #7 nut was easy to turn,replaced with stock nut(same)nice and snug.and .030+ in between spring coils.
started it up sounded good drove car wash to wash oil from engine compartment.
just before I got there I started hearing that damn ticking,washed it anyhow.
driving home it got worst and worst and start running bad...O.K. the cam must be going.

get home tear it down cam is fine,put it back togather and hear a cluning on start up.
turns out the bottom pulley is coming loose,remove belt and check with hand tick tick back and forth thats it I found it pulled it off just to be sure ........tick tick tick me off.

I have ordered a set off ploy locks from summit but I don't think thats it ,but just don't know what else to do.

I like to use about a 3 foot legnth of heater hose as a poor man's stethoscope. Might help you pinpoint where the noise is coming from.

engine shop told me to look at the screw in studs,said a guy last week had the same problem,he also had roller tips.
the studs were his problem,I'll check mine tonite.

I have a stethoscope but still can't tell were its coming from.

maybe from the same place as the voices in my head graemlins/clonk.gif graemlins/sad.gif

You don't by chance have fast bleed down lifters like Rhoades. Comp and Crane also make lifters like this that help with low end on big cams. These are known to be loud because of the fast bleed down rates.

Don't know for sure or not but the guy who mentioned the Rhoads type lifters may be on to something. I was strongly advised against using that type lifter by a pro engine builder who knows his stuff. The reason is they are designed to bleed down in an effort to " shorten the duration" of the cam and he said they can be very noisy! Turn tale and run quickly!!!!!!!!!!!! Maybe a stupid question but, you do have the correct size guide plates that match the pushrods? Both 3/8 and 7/16 were used. I suspect the small pushrods in the big guide plates could make some funky noises and cause various other problems. What non stock parts are you using? How are you adjusting the valves?

What cam/lifter break in lube are you using?

-Mark.

O.K.,
I haven't gotten back out to the garage yet this week to check the studs.

anyhow non stock parts:

.030 9.7-1 speedpro forged pistons

comp cams 292h kit (cam lifters springs seals locks)
comp cams roller tip rockers
comp cams push rods and guide plates
manly SS one piece valves

spring were checked and shimed and heads assembled at mach. shop.
heads never been cut.

on break in lost #8 intake lobe.
comp cams replaced cam/lifters.
after cam swap engine lost oil press.
pull it down oil pump and crank shot,turned crank another 10/10 to 20/20.
reassembled with new oil pump and bearings.

good oil press,but had alot of carb tuning issues,and noisey valves.

finally get carb straight,but still have noisey valves.
thought bad lifter,replace lifters with new set of comp cams lifters.

new lifters eat #8 exhaust lobe,

buy crane 272h cam/lifters(have same seat press, as comp 292h)
reassemble,adjust valves(running)all good ,
test drive,no power and noisey valves again.

pulled down to check cam ,cam is fine.

adjust valves 1st by comp instruction 1/2 turn past push rod resistance.

then running back off until clack,tighten until quiet,then another 1/2 to 3/4 turn.

while at idle all is quiet,revs up and gets noiesy,and stays noisey

still pulling my hair out!!!!!

thanks!

TADAA!!!

you guy's will never guess what it was! all this time it was a 15min job!

new ,but bad mechical fuel pump.pulled it let the car run with carb reserve and was as smooth as glass graemlins/hurray.gif
I'll put the new one on tonight!

the wife still wants to sell it though,but I think I've had a change of heart ;)

with the old pump in your hand squeeze it ,it makes a loud "click".
I think the 2nd cam went due to new lifters(what comp cams said,never new LIFTERS on an OLD CAM :confused: )

WHAT A RELIEF :D :D :D