What should an engine sound like?

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DartVadar

DartVadar

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I just broke in the cam in my 360, I changed the oil after the break and today I had it running to check oil pressure, temp little things. I was listening to the actual engine and could hear a slight noise, definitely wasn't a knocking noise, and it was coming from the top of the motor. It just sounded like valve train noise (I think?), kinda like a really quiet sewing machine or something. Valves are all adjusted good. It's really quiet, I can only hear it if I stick my ear close to the valve covers.

It's a comp extreme energy flat tappet cam, I've read that they can be kinda noisy, could that be what I'm hearing? I also haven't timed the engine completely, I just had it going for a few minutes, I'm planning on timing it and getting it ready to go for a ride this weekend.

Should I be concerned about this? Or is it to be expected? Slightly worried...
 
solid lifters? Yes, they are going to be a bit noisier than hydraulics......
 
69B-Cuda said:
solid lifters? Yes, they are going to be a bit noisier than hydraulics......
Click to expand...

Nope hydraulic lifter, sound kinda like solid lifters though. I mean you can't hear it while you are around the car, you can only hear it when you really listen. I don't know what else it could be besides valve train noise. It's not a knock, not a ticking sound, just kinda like consistent sewing machine noise...it's hard to explain what it sounds like.

Anybody else have comp xe cams? I have a xe268
 
Did you recently install aluminum valve covers? I've noticed valve train noise more sometimes after switching to them. I don't quite understand why but I remember when I first replaced my factory valve covers with aluminum M/Ts on my old Roadrunner years ago that it was noisier and I hadn't made any other changes.
 
Yup I did! Same kind as you mentioned too, M/T valve covers. I have roller rockers as well, I've heard they can occasionally be noisy.

I guess my main issue is should I be worried if it is in fact valve train noise? Because it really doesn't matter to me if I have that noise, but only if I know nothing is getting hurt in the motor.
 
DartVadar said:
Yup I did! Same kind as you mentioned too, M/T valve covers. I have roller rockers as well, I've heard they can occasionally be noisy.

I guess my main issue is should I be worried if it is in fact valve train noise? Because it really doesn't matter to me if I have that noise, but only if I know nothing is getting hurt in the motor.
Click to expand...

I know that you already realize that no one will be able to say for sure that there's nothing wrong. Even if everything was assembled correctly there's still those gremlins. I've seen a new cam eat up new lifters (Crower cam, Crane lifters) within the first hour of run time. Everything was pre-lubed too. My first guess is that you've got that 'hopefully nothing blows up here after I put it together' anxiety going on and are hearing the valve train noise amplified by those valve covers causing you to worry even more. But top engine builders will sometimes lose one before the car makes it out of the shop.

There is also the possibility that your rockers are not fully clearing those valve covers. When I sent Mike (at MRL) my Edelbrock aluminum valve covers to use on the motor he built for me he couldn't use them. The rockers hit. He installed Mopar Performance covers instead.

It's a pain in the butt to have to pull the valve covers off of a nice clean motor but if you're in doubt you probably should so you can inspect things further.
 
Do you have roller rockers? If so, that is probably it. For what its worth, my motor sounds like a big nasty sewing machine too if you stick your head under the hood (roller rockers + solid roller)....well, if there is such a thing as a big nasty sewing machine, lol! Probably nothing to worry about, but keep an ear out for anything strange.
 
I would have a look just to be sure the rocker shafts are oriented so the top oil flows on both sides, no scaring underside of the rocker covers, etc...
I just stated in another thread how engine building compares to child birth.
Being a tentative parent means paying attention and that's a good thing but...
some will wear out their hood hinges with worry. We'll watch a new baby sleep too so... It is what it is. Good luck with it
 
After I installed my comp 268 I had noise from the stock rockers. Switched to pro magnums, adjusted them and the engine was quieter. You still hear normal valvetrain noise, which is probably what you are hearing. I wouldnt worry too hard!
 
I will pull off the valve covers to see if the rocker arms are hitting. And yes I do have roller rockers.

I'm probably worrying for nothing, but I guess I'm picking up every little noise and thinking it's a big problem!
 
Come to think of It, when we started up my cousins mustang a while back it had a similar noise. But I fail to see how it could be completely quiet, there is alot of stuff going on in there even at idle.

But lets just say worst case scenario, what would a hurting cam sound like? Would I know if that really was the issue? Backfiring through the carb? because it has yet to do that, or even backfire out the tail pipe.
 
Bad cam sounds are back firing or not fully firing, rhythmic clunk or bang that is 10+ db louder than the rest of the engine sounds.

Do note that the bigger than stock cam that I'm sure your running will make a louder sound than the stocker which has a lame lobe and lift rate vs. the new cam. The aggressive lift rate on the lifters at low engine speeds can be heard. And as said above, different valve covers, etc.....

You broke the engine in and looked at the oil and oil filter to find nothing of note?
Your probably good. Enjoy the car and take note to what goes on until it performs with trust.

You did match valve springs to the cam right?
Used assembly lube, primes the engine before start up etc....
All the right things .....

Then you should be good. While nothing is perfect the basics should be done for best results and best chances of happiness for the engine, you and your bank account. ;)
 
rumblefish360 said:
Bad cam sounds are back firing or not fully firing, rhythmic clunk or bang that is 10+ db louder than the rest of the engine sounds.

Do note that the bigger than stock cam that I'm sure your running will make a louder sound than the stocker which has a lame lobe and lift rate vs. the new cam. The aggressive lift rate on the lifters at low engine speeds can be heard. And as said above, different valve covers, etc.....

You broke the engine in and looked at the oil and oil filter to find nothing of note?
Your probably good. Enjoy the car and take note to what goes on until it performs with trust.

You did match valve springs to the cam right?
Used assembly lube, primes the engine before start up etc....
All the right things .....

Then you should be good. While nothing is perfect the basics should be done for best results and best chances of happiness for the engine, you and your bank account. ;)
Click to expand...

Nope its definitely not louder than the exhaust, up front its pretty quiet and I standing beside the car you really have to listen to hear anything, once you get up close to the valve covers you can hear a noise. The carb sucking in air is louder...And my hardcore belt squeal that really annoying me...lol The car sounds really strong and healthy as well, so thats always a good sign.

After the break in the oil looked odd to me, but I made another thread about it and came to the conclusion that is was moly paste, break in lube and wear from breaking in rings, and everything else, everything was new in the motor. I found no chunks or anything in the oil, and it wasn't gritty at all. Just kinda darker than I would have thought. The oil filter looked pretty good, no chunks or slivers either.

Yes I had the right springs for the cam, and I primed the engine prior to starting, and LOTSS of assembly lube was used, as you can see I am a tad paranoid when I am unsure about things :D

I hope all is well, because as a student I cant afford to built it again!
 
DartVadar said:
After the break in the oil looked odd to me, but I made another thread about it and came to the conclusion that is was moly paste,....

and LOTSS of assembly lube was used, as you can see I am a tad paranoid when I am unsure about things :D

I hope all is well, because as a student I cant afford to built it again!
Click to expand...


Just some hindsight...

Maybe not use as much assembly lube next time, as the excess will just end up in your oil pan...



I would take the valve covers off and inspect the valve train. If everything looks good, then put it back together and it's probably just the way that your parts are supposed to sound. You say that it's not louder than the air intake for the carb, so it can't be too loud, or anything to worry about if your inspection goes well.
 
krazykuda said:
Just some hindsight...

Maybe not use as much assembly lube next time, as the excess will just end up in your oil pan...



I would take the valve covers off and inspect the valve train. If everything looks good, then put it back together and it's probably just the way that your parts are supposed to sound. You say that it's not louder than the air intake for the carb, so it can't be too loud, or anything to worry about if your inspection goes well.
Click to expand...

Good point, I will use less next time, I guess more isn't always better.

And I took the valve covers off after cam break in, everything was just how it was before the start up. It only seemed to make that noise after it got warm, thats why I recently noticed it, by accident too, I was just looking at something on the side of the carb and could hear a slight noise. I will inspect everything again just to be certain though. And yea the carb air intake isnt very loud, and its hard to hear over it, so its a barely audible noise, probably wouldn't hear it unless somebody told you about it. I guess I just have good hearing!

I guess I don't have alot going for me in terms of having a quiet valvetrain. Aluminum valve covers, roller rockers, and a comp Extreme Energy cam, which I have read about some people saying they almost sound like a solid lifter, so I don't think its uncommon to experience noise. Could be wrong though.
 
I've got a full Hyd roller on my 408 and sounds like a sewing machine. Love that valve train noise. It's normal. I'm running comps Muthr thumper cam.
 
Now I suppose you could add a gear drive to drown out that valve train noise. LOL

:scratch:

:scratch:

:butthead:

:poke:
 
I had a LS400 lexus and the only thing you could hear from that motor was the injectors clicking, unreal. 275hp to boot. My solid lifter 225 and 273 were pretty quiet too with full exhsust as well as my solid lifter 312 ford. Sewing machine sound, good!
 
I took a quick video of it running, it's hard to hear but during the middle of the video you can hear it.

[ame="http://s72.photobucket.com/user/kellyb43/media/Mobile%20Uploads/trimF6318C5E-7812-4965-A5E5-D65D2E68B30F_zps8dd2b3ee.mp4.html?sort=3&o=1"]trimF6318C5E-7812-4965-A5E5-D65D2E68B30F_zps8dd2b3ee.mp4 Video by kellyb43 | Photobucket[/ame]

As you can see I have to get that close to the engine to actually hear it.
 
I'm in the same boat. Every clatter, bang, clunk etc that originates from my car makes me worry.
 
I Have Used Comp. XE Series Cams In Several Builds (Prob. 6) And Every One Of The Had A Slight Tic From The Valve Train To Some Degree. The First Was A 340, After Re-Checking Pre-load, I Changed From The Stamped Rockers To Some Crane Iron's And It Helped Alot, But Still There. (Stamped Rockers Are Like Minature Cow Bells From Harmonics) The Valve Train Noise Is Just The Characteristics Of The XE Series Cam. Oune You Accept That, You Get Comfortable Hearing It, The Cams Work Pretty Well.
 
Yea it was hard to actually get the sound on video. But you could hear it. So it just sounds like normal valve train noise?
 
titan said:
I Have Used Comp. XE Series Cams In Several Builds (Prob. 6) And Every One Of The Had A Slight Tic From The Valve Train To Some Degree. The First Was A 340, After Re-Checking Pre-load, I Changed From The Stamped Rockers To Some Crane Iron's And It Helped Alot, But Still There. (Stamped Rockers Are Like Minature Cow Bells From Harmonics) The Valve Train Noise Is Just The Characteristics Of The XE Series Cam. Oune You Accept That, You Get Comfortable Hearing It, The Cams Work Pretty Well.
Click to expand...

Glad to hear that valvetrain noise is common, I just hope that is what I am hearing. I can live with it though if it is, and judging by the responses I am probably fine.
 
I think that everyone is hesitant to assure you that there's nothing wrong. No one wants to have said it's OK and then find out that you dropped a valve or something like that later. I seriously thought it might have been a bit noisy but not to the point that I'd be panicking. But I've known guys that were amazing at picking up on problem noises that I couldn't. An inspection of your oil and a look under those valve covers would give you more re-assurance.

If you've got a stethoscope (or at least a 3 foot length of garden hose) you could listen more closely along the lengths of each valve cover. I would think that the sound should be pretty consistent all around and if you were to find a spot that was a lot noisier then maybe have more reason for concern.
 
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