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ANOTHER Noisy Valvetrain Thread....

JG71B

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I've searched and searched...here, Google, all but facebook and nothing adds up. It's a bone stock 77 400 4bbl motor from a C body type car. "Supposed" 60k mile motor/trans. Is very clean inside and out. Was pulled before the car was crushed so I'll assume it sat for a minute. Cleaned it up, new gaskets headers, performer intake etc. Stock cam. Runs great and pulls good for what it is. The valvetrain is noisy as hell warm or cold. Worse cold (especially from 10w 40 to 20w 50) but, sounds like it goes away when high idling with the choke in use until you tap it down with the pedal then noisy again. Lifters seem pumped all the way, no crazy bent pushrods, no rounded lobes. I just cant make sense of it. Worn shafts or rockers? Pushrods ends worn? Oil psi is around 80 cold and 30-40 hot at idle and the rockers are holding pools of oil. I've made sure the exhaust is tight, flex plate bolts and crank pulley bolts. I am at a loss because the car is about done, the cruises are starting and this is killing it! Already redoing a leaking valley pan thats sucking oil in so may as well try and figure this out since Im there. Thanks in advance
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That first rocker in the bottom set
of pics looks like it's been hammered
by the retainer. The second rocker looks
like it's worn thru in the pushrod cup.
I'd say you're due for a new set of rockers.
I'm no pro on this and have posted here
for the same symtoms your engine is
experiencing.
Geoff2, Wietse, PRHeads, and others were
very professional at explaining what to check.
Thread is titled "Valvetrain Clatter/Noise".
(1STMP).
 
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The rocker shaft is loose in that last picture, causing the odd position of the retainer.
Any details known about the lifters? How much is the pre-load? (any wear in the components reduces pre-load)
Any specific bank or cylinder(s) that is noisy or all in general?
Oil pressure is good enough, were the rocker shafts installed in proper orientation? (Oiling holes facing down towards the valve springs)
 
Looking at the sediment build up on those rockers, I would say there is a digit missing from the front of '60k' miles.
If the lifters have the same mileage, then you could have sticky lifters. Since you have access to them, I would pull them apart one at time, clean them & re-assemble with clean oil. Make sure the inner piston moves up & down freely, not sticking because of deposits.
 
Looking at the sediment build up on those rockers, I would say there is a digit missing from the front of '60k' miles.
Also depends on how the engine was serviced, if oil changes were not done frequently can aid in dirty sumps, as well does running without PCV valve.

Highly unlikely, but also any brand of "variable" lifters will cause a lot of noise, but since this engine is likely not something seriously modified i doubt they used something special for lifters, probably standard type which are old and are worn or sticky.
As Geoff said, a dismantle and clean could help.
 
Also depends on how the engine was serviced, if oil changes were not done frequently can aid in dirty sumps, as well does running without PCV valve.......

I'm wondering if that build up on the rockers is soft from lack of oil changes or the top end got toasty at some point.
 
It's carbon deposits, normally engine oil supposed to "absorb" that and hold on to it, causing the oil to turn black. (some old engines which are drained you will see thick black sludge oil coming out, full of deposits)
With an oil change most of it will be coming out, prolonged driving on the same oil causes the oil to be saturated with deposits and can no longer hold any more, it will start to set off agains the metal block.
Also a PCV valve will help in removing the fumes from the engine sump and allow filtered air to enter the block, keeping it clean(er).
 
I've cleaned and rebuilt lifters but given the rocker arm condition it may be simpler and easier to just put new lifters and rockers in it.
The next question is how much gunk is in the galleries that feeds the valve gear?
Those would be tough if not impossible to clean with the engine in the car.
It always ends up with a "at what point to you stop?" thing with a used engine.
I don't think this engine is as clean as you might think perhaps someone did some cleaning on it because it had deposits at one time?
 
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Looking at the sediment build up on those rockers, I would say there is a digit missing from the front of '60k' miles.
If the lifters have the same mileage, then you could have sticky lifters. Since you have access to them, I would pull them apart one at time, clean them & re-assemble with clean oil. Make sure the inner piston moves up & down freely, not sticking because of deposits.
Ive bee told Sea Foam or replace a quart of oil with tranny fluid also.. Possible. Very well could be 160k miles. I HAVE seen worse inside others and they've purred w/o issue but ,anything is possible. A closer look lastnight I saw that the valve seals have been upgraded at some point to the seals that have the 2 wires wrapped around them (forget exactly what they're called) so someone's been in here before. That tells me who knows what else has been fondled. Also, the pic of the rockers was after them and the shaft was removed. It's laying in the valve cover in that particular pic to clarify. Here it is when I cracked it open after bringing it home last fall.....
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I measured the pushrods and picking up a set of new ones from Summit later today. Went in the shed and grabbed another set of rockers I've had for years. The cup area looks much better so, I'm going to use these.
What I took out...
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What's going on...
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I measured the pushrods and picking up a set of new ones from Summit later today.
Did you double check how much pre-load the old ones gave?
If they are short, the new ones will be short and you will still have insufficient pre-load on the lifters, should be having around .050" pre-load or so, maybe even more with stock stamped rockers.
 
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