Hydraulic lifters are... noisy ?
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
Hydraulic lifters are... noisy ?
Dunno. What do you think ? Does this sound normal ?
This is after one minute of running and real close to rockers. It’s less audible at a distance.
I don’t know if you hear this the way I do, but to me this doesn’t sound right. No amount of adjusting preload, static or dynamic, seems to make a difference.
The cam is supposed to have a noticeable lope. But I don’t think I like the idle.
I’m also getting a rapid vibration of my vacuum gauge needle. Slow motion shows it to be very regular.
Ignition is good.
carb is EFI
I just came from a more aggressive cam... well sorta. The vacuum was a stable 14.5 inches. I should be getting around 19 inches.
Compression test is around 200 PSI on all cylinders. Leak down is very good as well.
What happened ?
I installed a Comp Cams Extreme Energy Retrofit hydraulic roller cam and Comp Cams Hi-Energy hydraulic roller lifter.
Any thoughts ?
Could these be the incompatible springs ?
No binding of pushrods or geometry, etc.
This is after one minute of running and real close to rockers. It’s less audible at a distance.
I don’t know if you hear this the way I do, but to me this doesn’t sound right. No amount of adjusting preload, static or dynamic, seems to make a difference.
The cam is supposed to have a noticeable lope. But I don’t think I like the idle.
I’m also getting a rapid vibration of my vacuum gauge needle. Slow motion shows it to be very regular.
Ignition is good.
carb is EFI
I just came from a more aggressive cam... well sorta. The vacuum was a stable 14.5 inches. I should be getting around 19 inches.
Compression test is around 200 PSI on all cylinders. Leak down is very good as well.
What happened ?
I installed a Comp Cams Extreme Energy Retrofit hydraulic roller cam and Comp Cams Hi-Energy hydraulic roller lifter.
Any thoughts ?
Could these be the incompatible springs ?
No binding of pushrods or geometry, etc.
Last edited by DorianC3; Mar 2, 2021 at 04:10 PM.
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
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Racer
Joined: Oct 2017
Posts: 312
Likes: 64
From: Henry county ohio
I have full roller rockers, and they make a clicking sound from the clearance between the rocker stud and the ID of the rocker pivot.
With the engine off, see if you can move the whole rocker ***'y from side to side. If you can, that's a likely explanation.
Good luck.
Jeff
With the engine off, see if you can move the whole rocker ***'y from side to side. If you can, that's a likely explanation.
Good luck.
Jeff
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
I have full roller rockers, and they make a clicking sound from the clearance between the rocker stud and the ID of the rocker pivot.
With the engine off, see if you can move the whole rocker ***'y from side to side. If you can, that's a likely explanation.
Good luck.
Jeff
With the engine off, see if you can move the whole rocker ***'y from side to side. If you can, that's a likely explanation.
Good luck.
Jeff
Ha !!! Could it be that simple ???
Hmmm. That does make sense. That would also explain why putting the tip of a stethoscope to any of rocker studs reveals a distinct clacking sound for each. If it had been a lifter... not all of them would be making that noise. In this case, pretty much all the studs sound the same.
Last edited by DorianC3; Mar 2, 2021 at 06:05 PM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
That sounds terrible even without my hearing-aid. I would not want that nor would I leave it like that. That is the sound of parts breaking in the future.
How was the pushrod length verified with this new setup? Are you confident about the valvetrain geometry?
Are the pushrods a different diameter than what the guide plates allow? (excessive play)
On the rocker pivot shaft. Is it possible that they can be installed up-side-down? In other words, both sides of the pivot look exactly alike and not one side round, the other side flat?
How was the pushrod length verified with this new setup? Are you confident about the valvetrain geometry?
Are the pushrods a different diameter than what the guide plates allow? (excessive play)
On the rocker pivot shaft. Is it possible that they can be installed up-side-down? In other words, both sides of the pivot look exactly alike and not one side round, the other side flat?
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
That sounds terrible even without my hearing-aid. I would not want that nor would I leave it like that. That is the sound of parts breaking in the future.
How was the pushrod length verified with this new setup? Are you confident about the valvetrain geometry?
Are the pushrods a different diameter than what the guide plates allow? (excessive play)
On the rocker pivot shaft. Is it possible that they can be installed up-side-down? In other words, both sides of the pivot look exactly alike and not one side round, the other side flat?
How was the pushrod length verified with this new setup? Are you confident about the valvetrain geometry?
Are the pushrods a different diameter than what the guide plates allow? (excessive play)
On the rocker pivot shaft. Is it possible that they can be installed up-side-down? In other words, both sides of the pivot look exactly alike and not one side round, the other side flat?
I did verify the geometry. It’s spot on.
The rockers are made so that they will “top out” on the poly locks before they bottom out on the stud.
There is some play between the guide plates and pushrods. But I think it’s within spec. What clearance should there be ?
Melting Slicks
Joined: Jul 2006
Posts: 2,274
Likes: 481
From: Salmon Arm, BC
Your problem is the Extreme energy cam....the ramp rates on those cams are....well.....extreme. Mine sounded like a solid cam most of the time (just like yours does in the vid) and no amount of adjusting could get rid of it. I now have a slightly larger cam from Crower, no valvetrain noise at all. The only change made was the camshaft...., same lifters, pushrods, rockers and locks. I tell folks all the time to avoid this series of cams if they want a quiet valvetrain.
Do a search on the Extreme Energy series of cams, you'll get echo's of what I just said.
Do a search on the Extreme Energy series of cams, you'll get echo's of what I just said.
Last edited by OMF; Mar 3, 2021 at 12:03 PM.
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
To quote Spock: fascinating !
And that makes a lot of sense. The lifters are “Ho -Energy” but I was always intrigued by the “Xtreme Energy” cam. Were the really compatible? I did read something somewhere about the ramps.
I’ll do some research... but that makes a lot of sense.
It’s not the lifters. It’s the cam.
And that makes a lot of sense. The lifters are “Ho -Energy” but I was always intrigued by the “Xtreme Energy” cam. Were the really compatible? I did read something somewhere about the ramps.
I’ll do some research... but that makes a lot of sense.
It’s not the lifters. It’s the cam.
Thread Starter
Melting Slicks
Joined: Nov 2017
Posts: 2,341
Likes: 517
Thank you @sstocker31 I read a bunch of articles on the topic. This is exactly what I’m experiencing.
It does make me I have a solid cam under the hood. Fortunately I don’t drive around with my head under the hood and I can barely hear it from the driver’s seat.
i can get used to it (for a few years at least) as long as I know it’s normal.
Thanks !
It does make me I have a solid cam under the hood. Fortunately I don’t drive around with my head under the hood and I can barely hear it from the driver’s seat.
i can get used to it (for a few years at least) as long as I know it’s normal.
Thanks !
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,809
From: Cool Northern Michigan
I disagree. I have had an Extreme Energy cam for several yrs now with over 500 lift. Not a peep comes from my valvetrain. And mine is a Flat Tappet.
Your Roller should be even quieter than a peep.
Its not the cam. Its something else. The fast ramps you mentioned is valve opening action rate. Not closing rate. Noises come from the valves closing.
You say the rockers top-out before they bottom out on the stud. I suspect that they are not. When you think your valvelash is set, I think they are not. You have too much play. You stated the rockers move side-to-side easily. Can the pushrod be spun easily on a closed valve of course?
Your Roller should be even quieter than a peep.
Its not the cam. Its something else. The fast ramps you mentioned is valve opening action rate. Not closing rate. Noises come from the valves closing.
You say the rockers top-out before they bottom out on the stud. I suspect that they are not. When you think your valvelash is set, I think they are not. You have too much play. You stated the rockers move side-to-side easily. Can the pushrod be spun easily on a closed valve of course?
Last edited by HeadsU.P.; Mar 3, 2021 at 04:07 PM.