No luck Adjusting Rockers

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johnnycuda

johnnycuda

JohnnyCuda's 68
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Hey all, Motor: 71 340 J heads with hydralic cam & Speed pro adjustable roller rockers.
So i adjusted them with one full turn of preload.
They still chatter after running for a few minutes with great oil pressure 60-70 on start up and 25 and up when warm can i go more? should i go more? 1 1/2 ? 2 full turns?
Does this mean the cam is wiped out?
I just want the clatter to stop otherwise runs great!
 
Are the rockers hitting the valve pan covers?
 
What cam exactly, and did the noise change when you've tightented them?
 
Is oil splashing around if it's running with the VC off?
 
You don;t know anything else about it? Different camshaft designs and different lifter types need and like different preloads. That's why I was asking. In terms of "turns", I don;t use that method. I would pull the intake and visually verify and measure the preload. Set it that way, and then record what it needs to be turn wise. Some lifters are may just be noisier, and some blocks have sloppier lifter bores and have issues staying quiet.
 
...............and who knows it might not be the lifters that are noisy.
 
I'm pretty sure it's the lifters .
thanks for the help!
Maybe I should just throw a cam and lifter set and new chain in it to freshen it up?
but then what kind do I buy.
It has a stock bottom end 71 340 block J heads milled 30 tho air gap intake 600 edebrock carb with msd distributor and 6al box. 391 gears with a 4 speed .I was looking for 3:55 or 3:23. 454 lift cam sound good?

67Dart273 said:
...............and who knows it might not be the lifters that are noisy.
Click to expand...
 
If there's a problem, I'd advise to try and locate it before you swap parts.
But if you're certain it's just lifters - in terms of good power and reasonable cost - the Summit cams are good peices and cheap. Just mke sure to stick a set of valve springs in it too.
 
what procedure did you follow when adjusting them?
some hit the valve cover baffles with thin gaskets,but
that is usually quite loud.
 
When the exhaust rocker just starts to open the exhaust valve. Set the valve lash on intake rocker at this time. Continue rotating the assembly and stop when the intake rocker starts returning from full lift. The lash on exhaust can now be set. Continue this procedure for the remaining cylinders. nothing is hitting the baffles.
the motor was quiter a month a go now it's been getting noisier.
this is not a fresh motor, the motor has been built for a few years ago.
Maybe i have been romping on it too much!!

ir3333 said:
what procedure did you follow when adjusting them?
some hit the valve cover baffles with thin gaskets,but
that is usually quite loud.
Click to expand...
 
I'd say if it's been getting worse - best to pull the intake and look closely at it. If the cam's goign away best to catch it before it really goes and fills the engine with iron.
 
When I was building motors for a living, I didn't use the count the turn method. There's a chamfer inside the lifter before the bore for the inside piece's bore starts. I ran them down to the bottom edge of the chamfer and that was it. Never had a problem using this method. I would definitely isolate the noise before replacing though and figure our whats going on. I had my roller rockers hitting the springs and retainers. (Isky solid cam, SS valves, Crower double spring w/ dampners, retainers and locks, and Speed Pro roller rockers.)
 
Sounds like something is leaving the motor then. I'd definitely find it since it could be catastrophic!

johnnycuda said:
When the exhaust rocker just starts to open the exhaust valve. Set the valve lash on intake rocker at this time. Continue rotating the assembly and stop when the intake rocker starts returning from full lift. The lash on exhaust can now be set. Continue this procedure for the remaining cylinders. nothing is hitting the baffles.
the motor was quiter a month a go now it's been getting noisier.
this is not a fresh motor, the motor has been built for a few years ago.
Maybe i have been rumping on it too much!!
Click to expand...
 
yeah i guess so, I havn't been taken stuff apart on a regular basis.
tryin not too.
I paid 17.5k for the car just figured i wouldn't be doing this 6 months after purchase. I already changed the rear from a 430 spool to a 391 sure grip and wanna go to 3:55's still I put the stock tank & sender back in! also Wet sanded and polished the entire car.
Bought new weather strips for the doors, installed some mini Gauges, fixed the tail lights and park light issues. Still need a front bumper has fiberglass one now!, rear springs because i put lowering blocks in for now but rides hard with the mono leaf and caltracks. and tail pipes and put the heater box back in.
It never ends does it. LOL

moper said:
I'd say if it's been getting worse - best to pull the intake and look closely at it. If the cam's goign away best to catch it before it really goes and fills the engine with iron.
Click to expand...
 
ir3333 said:
what procedure did you follow when adjusting them?
some hit the valve cover baffles with thin gaskets,but
that is usually quite loud.
Click to expand...


He told you! He went "one full turn down"

To the OP:

Lemmie preface this by saying this is NOT personal so please don't take it as such. That is my disclaimer and I mean it.

You never ever EVER EVER EVER "just go X number of turns down". EVER. I don't care who told you to. Where you've read it. DON'T do it.

When you make hydraulic valve adjustments, you are adjusting lifter preload. Preload is the amount that the pushrod pushes the plunger into the lifter body when the cam is on the base circle of the particular lobe of the rocker that's being adjusted.

Here's where my disclaimer comes in. See that last paragraph up there ^^^^^? If you don't understand that, you have no business adjusting rockers. I'm not trying to be an ***, that's just the way it is. If I didn't piss you off, keep reading.

Lifter preload is "said" to be between .020"- .080". "One full turn" could possibly bottom the lifter plunger in some cases, depending on the thread pitch of the adjusters. Usually the cheaper brand rockers have very coarse adjusters that can bottom the lifter plunger really quickly.

So, when you make your adjustment, NEVER make it by counting the adjuster turns. GHEY!

Make your adjustment by watching the pushrod being depressed into the lifter plunger. Here's what you can do. With the cam on the base circle, tighten the adjuster to ZERO lash. That's the point where you have no more "up and down" slop between the rocker, pushrod and lifter WITHOUT depressing the lifter plunger any. Take a machinist's rule and lay it flat on the valve cover rail against the pushrod and mark the pushrod. Then adjust the adjuster on the rocker until your mark is about .030" DOWN toward the lifter from where it was. You just set lifter preload correctly for that one lifter. Repeat 15 more times.

Now.....this is all correct IF you are SURE you have hydraulic lifters. My guess is what's happened is, they have all been tightened down too far from what it sounds like. No telling what maladies that has caused. Good luck.
 
None taken !!! i appreciate the help I will have to look at it more closely.
the speed pro rockers seem to have a fine thread so i should be fine as far as adjusting them too much i certainly did it less than they originally set by a half turn.
thanks!!! this is the reason i was going to go with the stock rockers.
I bought a set but the push rods are different.
RustyRatRod said:
He told you! He went "one full turn down"

To the OP:

Lemmie preface this by saying this is NOT personal so please don't take it as such. That is my disclaimer and I mean it.

You never ever EVER EVER EVER "just go X number of turns down". EVER. I don't care who told you to. Where you've read it. DON'T do it.

When you make hydraulic valve adjustments, you are adjusting lifter preload. Preload is the amount that the pushrod pushes the plunger into the lifter body when the cam is on the base circle of the particular lobe of the rocker that's being adjusted.

Here's where my disclaimer comes in. See that last paragraph up there ^^^^^? If you don't understand that, you have no business adjusting rockers. I'm not trying to be an ***, that's just the way it is. If I didn't piss you off, keep reading.

Lifter preload is "said" to be between .020"- .080". "One full turn" could possibly bottom the lifter plunger in some cases, depending on the thread pitch of the adjusters. Usually the cheaper brand rockers have very coarse adjusters that can bottom the lifter plunger really quickly.

So, when you make your adjustment, NEVER make it by counting the adjuster turns. GHEY!

Make your adjustment by watching the pushrod being depressed into the lifter plunger. Here's what you can do. With the cam on the base circle, tighten the adjuster to ZERO lash. That's the point where you have no more "up and down" slop between the rocker, pushrod and lifter WITHOUT depressing the lifter plunger any. Take a machinist's rule and lay it flat on the valve cover rail against the pushrod and mark the pushrod. Then adjust the adjuster on the rocker until your mark is about .030" DOWN toward the lifter from where it was. You just set lifter preload correctly for that one lifter. Repeat 15 more times.

Now.....this is all correct IF you are SURE you have hydraulic lifters. My guess is what's happened is, they have all been tightened down too far from what it sounds like. No telling what maladies that has caused. Good luck.
Click to expand...
 
What kind of pushrods do you have now? If they are ball and ball they could be the wrong length. When you have the rockers adjusted, how many threads are showing on the under side of the rocker? Should not be many. Maybe 3.
 
They have ball and cup with the roller rockers that are on there now.
Not sure how many threads have to check!!!
can i use milimeters to measure the .30' you say too adjust the rocker? as i dont have a machinist ruler.

RustyRatRod said:
What kind of pushrods do you have now? If they are ball and ball they could be the wrong length. When you have the rockers adjusted, how many threads are showing on the under side of the rocker? Should not be many. Maybe 3.
Click to expand...
 
It's not .30. That's three hundred thousandths. LOL It's .030 or thirty thousandths. Yes, you can convert it to mm.

.030" = 0.7619999999999999 mm That's a hair over 3/4 a mm.
 
So is about three threads showing under the adjusted about .030 thosands?

RustyRatRod said:
It's not .30. That's three hundred thousandths. LOL It's .030 or thirty thousandths. Yes, you can convert it to mm.

.030" = 0.7619999999999999 mm That's a hair over 3/4 a mm.
Click to expand...
 
Somebody said somethin.............

Are you absolutely positively certain you have hydraulic lifters?
 
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