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Need help with ticking sound from a small block

RT6PK

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I have a 318 that I purchased from a member here with only a few thousand miles on it. There was a slight ticking sound from the valve train when I bought it. I installed a new stock 340 cam and lifters. The ticking sound is still there.

There is some slop between the intake rocker and push rod on the #2 cylinder. I do not see any uneven wear on that rocker, rocker shaft, or pushrod. I swapped that rocker and pushrod with the one from the #4 cylinder; and reinstalled the rocker assembly. I am aware of the offset to the rockers and made sure that I swapped a rocker with the correct offset. The slop is still there in the intake rocker on #2. That tells me that the issue is either with the lifter, cam, or possibly that valve and NOT the rocker or pushrod??? I pulled the lifter out, and it looks brand new. Just for fun, I bought a new lifter and will install it tonight.

My big question is, if the new lifter does not fix my problem, can I just install a slightly longer pushrod to take up the slop and stop the ticking? And if so, how do I determine that length pushrod to go with? Is it as simple as measuring the gap between the rocker and valve stem and adding that dimension to the length of my existing pushrod to calculate the length of a replacement pushrod?
 
I'll ask a couple of probably obvious questions here before the real engine guys show up:
-What oil did you use for break-in and are using now?
-Have the rocker shaft pedestals been machined?
 
I'll ask a couple of probably obvious questions here before the real engine guys show up:
-What oil did you use for break-in and are using now?
-Have the rocker shaft pedestals been machined?
My buddy actually did the installation. He used a custom blended synthetic with zinc and phosphorus. Plus cam lube. I do not know if the rocker pedestals were machined, however I do believe that either the heads were shaved or the block decked because an aftermarket aluminum intake manifold would not fit. The cast iron 4 bbl intake that the machine shop who built the motor used fits though.
 
whats the rocker shaft itself look like?
do you have a different one to swap out and try?
im surprised you only have one tick if the heads/block have been decked and you are running stock pushrods.
i would deffo get an adjustable pushrod mock it up measure it 3 times at least and then get all new ones.

im not a fan of break-ins with synthetics but im also oldschool so theres that.
the Racers can tell you whats good nowadaze.

edit,also,valvesprings...there shouldnt be any slop
id test the valvesprings,all of them too,starting with #2

btw,you Really should figure out whats been done to the motor.
while that cast iron will hold the seal for longer than an alum intake,
if it hasnt been cut to match then eventually the gaskets will fail.
 
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There are a lot of questions to answer. What did the original cam and lifters look like; any wiped? Did you do a proper break-in, doesn't sound like it. What do the new lifters look like, especially your #2? If an aluminum manifold doesn't fit, but the original one does, that tells me the machine shop, while fixing the problem of alignment due to milling the block and heads, did it wrong. The intake surface of the heads should have been milled, and not the intake. Now the original manifold will only fit this engine, and any other manifold will have to be milled to fit. If the intake side of the heads are milled, ANY manifold will fit properly. Moving the heads/rockers closer to the cam will not create loose rockers with OEM length pushrods, it would be tighter and hold valves open. Measure all push rods to verify length, look at the valve stem tips for evenness. They should all be roughly the same height. If one (the problem valve/rocker) is lower, the only reason could be a seat not installed/machined properly or a shorter valve. I would be half inclined to say remove the heads, and take them to a shop to check out the valves for sealing and proper height. Then have them mill 0.010" to 0.015" off of the intake side of the heads, so that any manifold will fit, and pitch the old manifold because it won't fit any other engine unless it ha been milled about the same.
 
If it had the ticking sound before and after the 340 cam install I doubt it is a flat cam lobe. What brand of cam and lifters? If it's Comp you probably have a bad lifter. Their hydraulics are noted for that.
 
Something else to consider...my 383 developed a tick within a few hundred miles after rebuild. I found out (the hard way) that the machine shop had not set the proper clearance on the new valve guides and one of the intake valves started sticking open. The ticking was the piston tapping the valve and closing it. I was fortunate that the pushrod fell off the rocker and bent before ending the valve. Pulled the heads and valves, found bronze smeared on the valve intake valve stems and a nick in the piston top. Cleaned it up, put it back together and been fine for almost 30 yrs.
 
“Slip in the pushrod? What is this? To measure for proper pushrod length, twist the pushrod checker until it starts to depress the lifter, making sure the pushrod is in the lifters proper spot and in the rocker arm spot proper.
(Sorry, it is an easy mistake to make sewn done by seasoned guys working to fast and/or not thinking while do it.)
Knowing what lifter you have or at least the amount of full travel should be known as well as far the manufacture or cam company wants the lifter to be depressed downwards by the pushrod, should be known.

Rhoades lifters want a shallow distance vs the standard ones Hughes engines uses. Hughes HP units want less preload vs the standard lifter but not as much as the Rhoades.

Aggressive cam ramps also can have lifters tick. This is also Aggravated by1.6 rockers. Loose lifters in there bore rocker causing a tick. Old lifters or high rate bleed lifters will tick. Loose engine clearances aid in bleed down pressure of the whole system as well leading to a momentary low oil pressure through out the whole system.

All lifters should be depressed at least to the min. or .020. This stops the plunger from hitting the retainer ring.
 
Make sure that you don't have an exhaust leak, can make the same kind of "tick" your describing...
 
What is the proper break in procedure for a new cam and lifters?
Use proper "Break-In" oil designed for flat tappet cams. Joe Gibbs Driven, Amsoil, or others. To my knowledge, there are no synthetic break-in oils. and your buddy adding ZDDP to synthetic oil does not make it a proper break-in oil. Using proper break-in oil, run the engine for 20-30 minutes at 1800-2000 rpm.
 
Thanks to everyone who replied. I put a new lifter in it, put some break in oil in it, went through the break in procedure. That seemed to do the trick, no more tick. Thanks again
 
I have a 318 that I purchased from a member here with only a few thousand miles on it. There was a slight ticking sound from the valve train when I bought it. I installed a new stock 340 cam and lifters. The ticking sound is still there.

There is some slop between the intake rocker and push rod on the #2 cylinder. I do not see any uneven wear on that rocker, rocker shaft, or pushrod. I swapped that rocker and pushrod with the one from the #4 cylinder; and reinstalled the rocker assembly. I am aware of the offset to the rockers and made sure that I swapped a rocker with the correct offset. The slop is still there in the intake rocker on #2. That tells me that the issue is either with the lifter, cam, or possibly that valve and NOT the rocker or pushrod??? I pulled the lifter out, and it looks brand new. Just for fun, I bought a new lifter and will install it tonight.

My big question is, if the new lifter does not fix my problem, can I just install a slightly longer pushrod to take up the slop and stop the ticking? And if so, how do I determine that length pushrod to go with? Is it as simple as measuring the gap between the rocker and valve stem and adding that dimension to the length of my existing pushrod to calculate the length of a replacement pushrod?
I know you said it only had a few thousand miles on it but 318's were notorious for burning the exhaust valve which caused a tick sound. But to answer your question. You can buy a adjustable push rod that is used to set the length ( you can not run the engine with this rod) it will come with instructions. Follow them and have a rod built. But my question is why is only one pushrod loose?
 
What is the proper break in procedure for a new cam and lifters?
It is in the oil you choose. You need an oil with a high zinc content. Today's oil has a very low zinc and phosphorous content. (commonly refereed to as ZDDP) They removed it because it vaporizes and is sucked up by the PVC valve and burned. Once combusted, the ZDDP eventually coats the precious metals in the catalytic converter, reducing its efficiency. During the assembly process you need to coat the cam lobes with a good assembly lube. I buy break in oil and add zinc additives. Before starting your engine you need to prime the engine and have the timing set as close to base as you can and carburetor full of gas . Cranking an engine with it not starting will wipe out the lobes when the assembly lube is pushed off the lobes. When the engine starts, immediately take it to a minimum of 2500 RPM and hold it for a minimum of 20 min. Cam lobes are splash lubricated and you need the RPM's to ensure good lubrication. I very the RPM's to ensure all surfaces get coated. During this time you need to watch the temp and oil pressure, it is a lot of RPM's with the car not moving. When the 20 min is up return the engine to a normal idle. I add zinc additives to every oil change, some people say you do not need to do this ounce the cam is broke in but a flat tappet is a flat tappet and there is a lot of friction and zinc and phosphorous was added as a friction reducer. My 2 cents.
 
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