Cant make this valve train noise go away!

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Krazed

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Ok, so I have a 1967 coded 340 block, It has the following in it:

Eagle H Beam rods
TRW 340 replacement pistons
Lunati 60403 cam and lifters (a package/kit from summit racing)
Edelbrock 340 Heads
Summit 5/16th pushrods 7.5" long (Measured and fit with length checker)
Stock stamped steel rockers
Edelbrock Airgap RPM Intake
TTI Headers
TTI Exhaust


For the life of me I can't get the valvetrain noise to go away.

Here's what I've tried, and I'm hoping for more suggestions.

I have:
-Replaced lifters, 4 times, 4 different lifters and 2 different cams total. Including Engle and Lunati.

-Swapped pushrods, and rocker arms. I've used stamped steel most recently, and prior the 273 adjustable rockers. Measured pushrod length properly both times and even custom ordered pushrods.

-Checked for exhaust leaks on the headers, and collector flanges. NO Leaks what so ever, checked while running for exhaust coming out, as well as 3 sets of gaskets on both collector flanges and the header flanges on the heads.

-Completely rebuilt motor from scratch, this includes machine work most recently, replaced nearly all parts inside. This means tear down, clean, machine, clean, rebuild, check specs on everything, clearances, etc.

-And lastly as a desperate attempt, I have torn off the intake, heads, and elongated the pushrod holes to make room for any weird pushrod angles hitting the Edelbrock heads as I've read happens. I found a sticking lifter, took it out, cleaned it, it worked perfectly afterwards.

Also changed my oil every time I did anything. I use 30wt VR1 racing oil, and a Napa Gold filter (aka Wix).

The noise still remains, as loud as ever.

I am going insane! I need help before I pull the motor and tranny out and sell both just to put in modern parts.
 
I'm thinking maybe something in the valve spring area since everything else seems to have been scrutinized. If it's there, it can't be too heavy or there'd be bent pushrods everywhere. Maybe the beginnings of coil bind or light contact in the retainer-valve guide area? I'll keep thinking on it in hopes of an epiphany.
 
I had a noise that I thought sounded like an exhaust leak coming from the passenger side of the engine. Thought I might have had a bent rod. Turns out the head gasket had blown and that was the noise. Changed out the head gasket and the noise went away. Not sure if this is your problem as it seems you have a bit more mechanical experience than I do. The funniest thing about the gasket is I always thought that when the head gasket blew there would be some evidence of coolant mixing with oil and what not. This didnt happen so I was stumped for a few weeks. Good luck!
 
Hmmm I'm not positive it would be head gasket, as I've gone through a few sets now with rebuilds and new heads and such.

Also forgot to mention that this is a hydraulic cam/lifter setup. Preload is set to .050.

The idea for it being light coil bind does sound interesting though, I did check and there didnt seem to be any hints of it, but I am using stock edelbrock head springs with the Lunati cam.
 
Krazed said:
The idea for it being light coil bind does sound interesting though, I did check and there didnt seem to be any hints of it, but I am using stock edelbrock head springs with the Lunati cam.
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By the numbers, it should be okay (.513 vs .575). This is a head-scratcher.
 
Is the noise still there with the valve covers removed? Any visual signs of contact between rockers/pushrods and covers?
 
Yes the noise is still there without the valve covers. I also have the aluminum mopar performance ones, so that doesn't help increasing the noise volume.

I also tried doing the, push on the rockers while the engine is running, trick to see if i could quiet it down. That didnt do anything at all.

Honestly, it sounds like I still have bad/sticking lifters, but there is no loose rockers, and they pump up 100% fine and dont bleed down.
 
what compression are you running and what octane fuel do you normally run and also what elevetion is your town
 
1qwikScamp said:
what compression are you running and what octane fuel do you normally run and also what elevetion is your town
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I use 90 octane with Half a can of torco just incase. I also have 10:1 compression. It's not pinging if that's what you're getting at. I know the sound of that and I hear it whenever it pings. Usually that's at low rpm in 4th gear.
 
This doesn't help but years ago I built a 70 340 and had the same problem. I gave up trying to find the noise and drove the hell out of it. I too thought it was in the valve train, but I never did solve it. On the other hand it never gave me a problem. Are you getting good oil to the top? How is the oil preasure? Are the lifter galley plugs in front and rear?
 
i think what your hearing is the headers pinging.the last 340 i herd like that was a good runing car.if the oil psi.is good runer i know alot of guys would love to here that.
 
That's a pretty big hydraulic, I don't see a problem with some valvetrain noise with a hipo cam and lifters. I'd just drive it, if there is really something wrong you'll find it.
 
Can you post a video of the sound you're hearing?

Any chance that your converter bolts are hitting the dust cover (yank the dust cover off to find out...after pulling the starter).

How much clearance between rockers? Can they shift side to side more than .035?

Just throwing out ideas...

Have you tried a different distributer? I had one with a bad bushing years ago that made a weird squeaking noise that was hard to track down.
 
I dont have a converter really, as its a 4 speed manual. I torqued all of my flywheel and pressure plate bolts to spec as well.
 
i have heard of cams accually pushing the lifter up far enough out of the lifter bore that it bleeds the pressure down via the first groove on the lifter you said you have had some lifter problems and that is a large hyd cam might be worth looking into
 
1qwikScamp said:
i have heard of cams accually pushing the lifter up far enough out of the lifter bore that it bleeds the pressure down via the first groove on the lifter you said you have had some lifter problems and that is a large hyd cam might be worth looking into
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That is usually on roller lifters, I've never encountered this on a hyd. or solid lifter.
 
My father in laws truck suddenly developed a rocker like tick. After replacing all the lifters and resetting valve lash several times the noise was still there. No brocken rockers,springs,exhaust leaks etc.Everything was stock. Turned out to be a cracked flexplate.
 
I have the next bigger Lunati in my 360 (60404lk) and it has a little lifter tick. Allot of fast rate cams are noisy because they slam open and slam close the valve pretty violent. Much like a solid lifter cam. Maybe that's all your hearing. If you can post a video of it running so we can hear the sound that might help.

I just remembered one I had a few yrs. ago that had some pretty announced lifter noise. The rocker arms (stock stamped arms) were slapping the valve spring retainers at full lift. Have you looked at that.
 
fishy68 said:
I just remembered one I had a few yrs. ago that had some pretty announced lifter noise. The rocker arms (stock stamped arms) were slapping the valve spring retainers at full lift. Have you looked at that.
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Ill see if I can get a video of it tonight.

I didnt think about the stamped arms slapping the valve spring retainers... that would make some sense considering how flat they are on the bottom.

I was going to try putting my 273 adjustable rockers back on tonight to see what it did again.

Also, I think I forgot to mention this is barely predominant at low rpm, but very much so above say 1500, and extremely loud at 2500+ under load.


Thank you all VERY Much for all the input and suggestions. I'll look into some tonight and post my analysis.
 
You could also do a thread search from 340Fastback.He had some noise issues also..Eddy heads,340.I can,t remember what it was,but he found the problem.Maybe someone else will remember and chime in?Good Luck!Sorry,it was Fastback340 that had the issues,I,m sure he,s found his problem!
 
Krazed said:
Ill see if I can get a video of it tonight.

I didnt think about the stamped arms slapping the valve spring retainers... that would make some sense considering how flat they are on the bottom.

I was going to try putting my 273 adjustable rockers back on tonight to see what it did again.

Also, I think I forgot to mention this is barely predominant at low rpm, but very much so above say 1500, and extremely loud at 2500+ under load.


Thank you all VERY Much for all the input and suggestions. I'll look into some tonight and post my analysis.
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I've just built a 68 340 and having the same noise issues.tried all the above and no change in noise.I'm thinking mine is the wrist pins the bushing in the rods where plenty worn.my machinist said they'd be fine.
 
Yeah im not sure mine is the bushings in the rods, they are fairly tight. Oddly, I found out today that the noise quiets down a lot after 3000 rpm's. It's especially loud at 2500, but I cant get it on camera. The car is just too noisey with the exhaust haha.

I'm going to be ordering some Comp Cams roller rockers tonight, we'll see if this and new pushrods fixes the issue at all.
 
Dont mean to steal the thread but I have a stock 360 with a rattle like you described at about the same rpm range with good oil psi cold or hot. Mine is also backed by a 4 speed. I think it may be a wrist pin or piston slap but havent checked into it. Hopefully this will help someone diagnois your trouble.
 
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