Fresh 302, block was decked, valve train noisy

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Brooks James

Brooks James

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302 Ford, yes I know sacrilege
Fresh stroker to 347 build
Block was decked, amount unknown
Stock length pushrods, Comp cam hydraulic and lifters, roller rockers ,
Valve train was noisy, adjusted rockers, mostly quiet.
Took it for a drive, valve train noisy again.
I'm aware that too short a pushrods can cause noise. How about ones too long ?
I
 
Brooks James said:
302 Ford, yes I know sacrilege
Fresh stroker to 347 build
Block was decked, amount unknown
Stock length pushrods, Comp cam hydraulic and lifters, roller rockers ,
Valve train was noisy, adjusted rockers, mostly quiet.
Took it for a drive, valve train noisy again.
I'm aware that too short a pushrods can cause noise. How about ones too long ?
I
Click to expand...
Too long you won't get the valves to seal, won't start very easy or at all, just depends on how too long they are !
 
I'm not sure if this is your noise problem but with non factory rockers you have to check to see if the rocker sits on the valve properly with the pushrods that you have. I had one engine that wouldn't oil the rockers if the pushrods were even a hair too long.
 
What heads and block? wWat are you using to mount the rockers? i.e. studs and guide plates or bolt down?

How are the rockers adjusted? i.e. by running the nut up and down the stud or with adjusters at the push rod? What brand of rockers?
 
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What you need to do, is learn how to measure for proper pushrod length. Then get back to us. lol
P.S we are Mopar mechanics. lol Ford will cost you extra. :D
 
Brooks James said:
302 Ford, yes I know sacrilege
Fresh stroker to 347 build
Block was decked, amount unknown
Stock length pushrods, Comp cam hydraulic and lifters, roller rockers ,
Valve train was noisy, adjusted rockers, mostly quiet.
Took it for a drive, valve train noisy again.
I'm aware that too short a pushrods can cause noise. How about ones too long ?
I
Click to expand...

When you adjusted the roller rockers to work with the hydraulic cam, did you adjust them down 3/4 of a turn after Zero Lash.

This gives the hydraulic lifter the proper preload. If you just adjusted them to Zero Lash, they are going to rattle.
 
So the block was decked, the cam and lifter specs were changed, there's roller rockers, and for some reason the stock length pushrods?

Any one of those things can change the geometry enough to need a different length for the push rods, and we haven't even addressed anything done to the heads, valves or valve springs yet.

Those pushrods being the correct length has to have similar odds as winning the lotto, all the aftermarket parts and changes magically stack tolerances to zero so the factory length push rods fit? Not with my luck!
 
There should be a thread that states Comp lifters are junk. I never saw so many that are having problems with comp lifter. My son won't install them on any builds if he assembles the engine and runs it on a run stand. He got sick and tired of chasing the ticks.
 
If I was to take a guess your cam is going flat. There has been a ton of cams and lifters going flat in the last couple of years, and a big chunk of them are coming from Comp Cams. Check your lifters and cam ASAP.
 
Lifter and lobes ok
There is not enough oil in the rockers arm except for one which is near the
The camshaft bearing with the oil feed hole in it. The one rocker arm is getting plenty of oil through the pushrod

So could it be possible the the cam bearing was installed partially cockeyed that reduces the oil flow significantly or the bearing spun ?

I've read some posts that stated that lifter preload on small for fords need only be off a little bit to greatly reduce oil thru the pushrods ??

Your thoughts ?
 
What heads are on that engine? What type of valvetrain are you using? Do you have screw in studs and guide plates? Are the lifters pumping up with oil?
Do you have good oil pressure?
 
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Complete Comp valve train, will quiet down at idle, after brief drive valve train clatter
 
What happens when you race a 302 Ford.

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Biggest issue with new style lifters is too thick oil, there designed for thinner oil like 5-30 or 10-30 in 90 deg. weather plus saves the bottom ends. Look at NASCAR they run 0 to 0-5 weight oil.
As long as engine assembled properly.
 
Brooks James said:
Complete Comp valve train, will quiet down at idle, after brief drive valve train clatter
Click to expand...
Do you have an oil pressure gauge? If the clatter quiets down at idle, and after you drive it you have clatter, it would indicate to me that you are loosing oil pressure to the lifters at higher engine speeds and they are pumping down. First thing you need to do is to put a good oil pressure gauge on the engine and see what it is doing. Your valvetrain clatters because of excess clearance, if you are idling the car and the valvetrain is quiet, and then you run it and it starts clattering then you have somehow introduced clearance on the valvetrain by driving it. If you then idle the car again and the valvetrain quiets down, there is little doubt that the only thing that can cause this is the hydraulic lifter. The hydraulic lifter is designed to keep the valvetrain at zero lash by taking up any clearance that there may be in the valvetrain. As soon as you have clearance you will have clatter. The lifter works with oil pressure, if you loose your oil pressure the lifter will no longer stay "pumped up" and you will end up with clearance on your valvetrain and have all that clattering noise. You really need to stop running that engine until you get a good oil pressure gauge on it. There could be a ton of things happening here, you could have your oil pump pickup too far from the bottom of the pan, excess clearances in your bearings, a bad oil pump. I know that the 302 Ford has a plug on the inside back of the block on the passages that feed the lifter galley, if that plug popped out you would have no oil pressure to the lifters, but I don't think that would be your issue as it seems that at idle you have enough oil pressure to the lifters.
 
As for the too long pushrod question, if the pushrods were too long your valves would just never close. You shouldn't have any valvetrain noise with too long of a pushrod as the problem with the scenario is that you would have no clearance anywhere. If the pushrod where too long then it would take up all the clearance that is built into the lifter, and it would basically jam the lifters internal piston into the bottom of the lifter. Since you now have no clearance anywhere the valves will basically never close. If all the pushrods were too long you would probably have no compression, the engine would not start.
 
HSDemon said:
Do you have an oil pressure gauge? If the clatter quiets down at idle, and after you drive it you have clatter, it would indicate to me that you are loosing oil pressure to the lifters at higher engine speeds and they are pumping down. First thing you need to do is to put a good oil pressure gauge on the engine and see what it is doing. Your valvetrain clatters because of excess clearance, if you are idling the car and the valvetrain is quiet, and then you run it and it starts clattering then you have somehow introduced clearance on the valvetrain by driving it. If you then idle the car again and the valvetrain quiets down, there is little doubt that the only thing that can cause this is the hydraulic lifter. The hydraulic lifter is designed to keep the valvetrain at zero lash by taking up any clearance that there may be in the valvetrain. As soon as you have clearance you will have clatter. The lifter works with oil pressure, if you loose your oil pressure the lifter will no longer stay "pumped up" and you will end up with clearance on your valvetrain and have all that clattering noise. You really need to stop running that engine until you get a good oil pressure gauge on it. There could be a ton of things happening here, you could have your oil pump pickup too far from the bottom of the pan, excess clearances in your bearings, a bad oil pump. I know that the 302 Ford has a plug on the inside back of the block on the passages that feed the lifter galley, if that plug popped out you would have no oil pressure to the lifters, but I don't think that would be your issue as it seems that at idle you have enough oil pressure to the lifters.
Click to expand...
Uhhh Yep. Try a different oil filter with a better bypass, check to see if the pick-up screen is too close to the floor of the sump.
 
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