New Small Block Stroker Engine Noise

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I think I am going to run the engine, shut it down, and carefully adjust all the valves. See what that gives me.
 
i wonder if too much preload can cause the lifters to be noisy because the plungers arent up on the retainer clip and when lifters go down hole the plungers tap when the plungers released and hits the retainer. by retainer i mean the clip at the top of the lifter
 
you may have some oil up top, but it might not be enough... i would swap out a factory bolt for the stud where the oil comes up as an experiment.
 
moper said:
you may have some oil up top, but it might not be enough... i would swap out a factory bolt for the stud where the oil comes up as an experiment.
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Moper, it was tight between the stud and rocker shaft, not a lot of room for oil to get up there. I do have the old engine complete I could take the bolt off of it and give it a try. I could also clearance the stud some to allow more oil to come up.
 
daredevil said:
i wonder if too much preload can cause the lifters to be noisy because the plungers arent up on the retainer clip and when lifters go down hole the plungers tap when the plungers released and hits the retainer. by retainer i mean the clip at the top of the lifter
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I have read too much pre load will cause the engine to back fire because the valves will not close all the way.
 
Were the lifter bores bushed? Is it possible that the oil goove/hole in lifter is coming above lifter bore when cam is at max lift. Have heard of that happening before. Just a thought
 
mod38-1 said:
Were the lifter bores bushed? Is it possible that the oil goove/hole in lifter is coming above lifter bore when cam is at max lift. Have heard of that happening before. Just a thought
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That is a good thought and I did have that problem with the first retrofit roller cam I bought. I had a custom lower base circle cam ground. During assembly I pressurized the oil system and spun the cam with lifters in place to make sure no bleeding off was occurring. So I am 100% sure I don't have that problem.
 
340s I had a set of comp Magnum rockers like you have there and also used their pushrods and at first the pushrods I had were a little too long so I had to back the adjuster out to where only about 1 thread was showing so as to not have too much lifter preload and it was real noisy like yours. I found what was happening was the pushrod cup on top was contacting the rocker arm at full lift. I swapped the pushrods for shorter ones so then I had about 2-1/2 threads on the adjuster showing and the noise left because the pushrod cup no longer hit. You might have a look at that.
 
What brand are the lifters ? There have been alot of problems with the Comp lifters. Apparently they do not do a good job of de-magnetizing the bodies after maching them and it causes the valve inside to stick to the bottom and not allow enough oil to get inside.The cure for this is to remove the lifters from the engine and take them to a machine shop that can de-mag them for you,any shop that has a machine for magging cranks can do this.If it is a Crane they recommend .090 preload ,which is about 1 1/2 turns,it should have stated that in the instructions.
 
fishy68 said:
340s I had a set of comp Magnum rockers like you have there and also used their pushrods and at first the pushrods I had were a little too long so I had to back the adjuster out to where only about 1 thread was showing so as to not have too much lifter preload and it was real noisy like yours. I found what was happening was the pushrod cup on top was contacting the rocker arm at full lift. I swapped the pushrods for shorter ones so then I had about 2-1/2 threads on the adjuster showing and the noise left because the pushrod cup no longer hit. You might have a look at that.
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Fishy, the top of my push rods have a ball end, no cup. The Comp Cams Pro Magnum rocker arms come standard with a ball end adjuster on them. To run a cup type push rod the adjuster would have to be changed?
 
ramcharger said:
Are you using a windage tray? Could the rods be hitting it?
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No windage tray is being used. I also removed the torque converter dust cover to rule that out. Years ago my 340 had the torque converter bolts whacking the dust cover because the oil pan gasket was not in straight. And that noise made it sound like a rod was knocking, it was loud.

I do think the crank is smacking the oil dip stick because its bent and I know if was not bent prior to starting the engine. So I am going to run it with the dip stick out while diagnosing this noise.
 
Monte said:
What brand are the lifters ? There have been alot of problems with the Comp lifters. Apparently they do not do a good job of de-magnetizing the bodies after maching them and it causes the valve inside to stick to the bottom and not allow enough oil to get inside.The cure for this is to remove the lifters from the engine and take them to a machine shop that can de-mag them for you,any shop that has a machine for magging cranks can do this.If it is a Crane they recommend .090 preload ,which is about 1 1/2 turns,it should have stated that in the instructions.
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Monte, they are Crane lifters. The Crane documentation that came with the lifters says pre-load should be between .020" to .060":

http://www.cranecams.com/?show=techarticle&id=2

The lifters I have are Retrofit Roller lifters. Where did you get .090" pre-load from?

I think I am closer to .20" (1/2 turn past zero lash) so I am going to try 3/4 turn and see how it runs.
 
I called Crane and they said I should be running .060" pre load. Sounds a little high to me but that is what he said to do. He said 3/4 to 1 full turn on the adjuster with 3/4 turn being the most common.
 
ramcharger said:
Any luck on pulling the dipstick out?
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I am going to readjust all the valves with more pre load and run it with dipstick out for now. The crank has hit the dip stick because it is bent and it was straight (new) prior to running the engine.
 
I read the post on Moparts... I didnt realize they might want that much, but hey, stranger things have happened. So long as the noise goes away...
 
340sFastback said:
Fishy, the top of my push rods have a ball end, no cup. The Comp Cams Pro Magnum rocker arms come standard with a ball end adjuster on them. To run a cup type push rod the adjuster would have to be changed?
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Ok. The ones I had were a few yrs. old and used pushrods with a cup on top. They must have changed them somewhere down the line.
 
OK

This is something to look into, rather than just take me at my word, because I cant seem to find my source.

I seem to recall reading someplace that the link bars on the retrofit lifters have to be facing inwards towards the cam, rather than towards the cylinder head. Is it possibly that the link bars are hitting on something?

Also, is that a Cobra R in the background?
 
LXguy said:
OK

This is something to look into, rather than just take me at my word, because I cant seem to find my source.

I seem to recall reading someplace that the link bars on the retrofit lifters have to be facing inwards towards the cam, rather than towards the cylinder head. Is it possibly that the link bars are hitting on something?

Also, is that a Cobra R in the background?
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Crane specifically states link bars toward the head and there is tons of clearance where they ride. I did have to clearance the block a small amount on the upper side of the lifter valley to get them in though.

Red SRT-4 in the back ground.
 
moper said:
I read the post on Moparts... I didnt realize they might want that much, but hey, stranger things have happened. So long as the noise goes away...
Click to expand...

Yes I called Crane and they say .060" pre load. I asked him a few times because that sounds like a lot of pre load to me but they insist that is where they should be set. The guy didn't look it up and he didn't even hesitate saying .060".

With Comp Pro Magnum roller rockers is that 3/4 turn or one full turn or what? I was gonna try 3/4 turn, run it, and see what happens. I could try 1 full turn if its still noising. More then one turn is probably not an option.
 
Wow,thats a LOT of preload..i think my Lunati cam is zero and just a 1/4 turn..
 
The last time I ran a hydraulic roller I went though the samething The cure was 1 to 1 1/2 turns of preload witch is .042 to .060 preload with a 3/8 24 thread adjuster. Chrysler had the same problem with there first roller motors in the late 80s. They recalled the 318 and put longer pushrods in them. The only other thing I can think of is if your lifter and pushrod have the holes for oiling through the pushrod you could be bleeding off to much oil pressure to the top end.
 
19DART66 said:
The last time I ran a hydraulic roller I went though the samething The cure was 1 to 1 1/2 turns of preload witch is .042 to .060 preload with a 3/8 24 thread adjuster. Chrysler had the same problem with there first roller motors in the late 80s. They recalled the 318 and put longer pushrods in them. The only other thing I can think of is if your lifter and pushrod have the holes for oiling through the pushrod you could be bleeding off to much oil pressure to the top end.
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Welcome!

That's what I'm talking about! Great info.
 
Thanks for all the suggestions guys. I wanted to warm the engine up prior to adjusting the valves. So I adjusted the timing some more and tuned the car a little while it was warming up. That seemed to quiet it down some and the noise made me think it was a header leak. It seemed to be noisier on one side so I decided lets take the header off and see. This is what I found:

HeaderGaskets.jpg
 
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