Noisy valvetrain

[Guest]

Since I've gotten the 6 back on the road, I notice that with the new cam (S2 from Ted Schumacher) my roller rockers are noisy as heck. I have a cast aluminum valve cover and the whole thing sounds like a cheap sewing machine. The auxillary oil feed is working fine, I have a ton of oil up there all down the line when pumping. The noise is so noticeable that it is a nuisance. I checked all my clearances after about 300 miles and nothing really moved. Set the intake at .016 and the exhaust at .018. Are these things usually that noisy? Don't remember it being that bad before. The head was rebuilt and everything in good shape.

 

[kodanja]

Turn up the stereo.....

Thanx for that info, cuz I was going to get the aluminum rockers , now I'm not so sure...


How Is the engine performing?

 

[vettedog72]

With that much gap, you can expect a LOT of noise. I don't know what your gap should be, but i know 0.016 or 0.018" is big for valve clearence. Just an opinion.

 

[DrEntropy]

My guess is it runs like a scalded dog. The alloy cover and the (necessary) wider clearances make for an AMPLIFIED amount of noise. You're in a "live with it or not" circumstance. A possible damping of Db could be had by going back to the original VC... less bling, but a bit lower noise level.


..."careful what you wish for"... :smirk:

 

[TR3driver]

Obviously, your exhaust is not loud enough !


You could also try putting some insulation under the hood and on the firewall, to absorb some of the noise. There was a fellow selling custom-cut foam insulation pads on eBay, but I don't see him at the moment.

Vettedog, that's no doubt the specified lash for that cam. 'Performance' camshafts almost always take more lash than the stock camshaft; since they are optimized for performance and not noise.

 

[Andrew Mace]

My guess is it runs like a scalded dog. The alloy cover and the (necessary) wider clearances make for an AMPLIFIED amount of noise. You're in a "live with it or not" circumstance. A possible damping of Db could be had by going back to the original VC... less bling, but a bit lower noise level....

And here I'd always thought that the thicker cast alloy valve covers tended to quiet things down more than the thin stamped sheet-steel originals. Or perhaps the alloy covers are "jus' like ringin' a bell"?

 

[TR6oldtimer]

Nah, Bill's valve lash and high lift cam are causing the rockers to hit the valve cover... :laugh:

 

[RonMacPherson]

Query, why the external oil feed?

Roller rockers require less oil, lubrication, to operate at optimum. So with the external oil feed sounds like overkill..

 

[70herald]

My guess is it runs like a scalded dog. The alloy cover and the (necessary) wider clearances make for an AMPLIFIED amount of noise. You're in a "live with it or not" circumstance. A possible damping of Db could be had by going back to the original VC... less bling, but a bit lower noise level....

And here I'd always thought that the thicker cast alloy valve covers tended to quiet things down more than the thin stamped sheet-steel originals. Or perhaps the alloy covers are "jus' like ringin' a bell"?

I also was under the impression that they would tend to quite things down a bit. I got my nice shiny new alloy vc in the mail recently and hopefully will have get my head back tomorrow so I guess I will have to test this out. Of course since the old tin pan is so bent that oil leaks no mater what I do, the alloy vc is going to stay even if it does make noise!

 

[GreenOne]

Here is the link for the hood insulation kit if you are interested.

https://www.928leathershop.com/Hood_Liner_Heat_Shields.html

 

[TheSearcherMan]

I run at least that much clearance, stock valve cover, valve train noise is not noticeable. at all. You have something wrong.

 

[Don Elliott]

Why don't you go straight to the top and ask Ted directly for his opinion about the noise and the gap.

 

[John_Mc]

Obviously, your exhaust is not loud enough !

Have you seen the afterburners Bill has on his car? I'm figuring the valve noise must be REALLY loud to be noticeable over those!

 

[Brosky]

Bill,

My TH5 Cam from BPNW is set at .014" Intake and .018" Exhaust and it is no louder than the stock cam, which made no noise at all.

Is there any movement or excessive side play in those roller rockers?

 

[AltaKnight]

I've got the same cam and valve clearances as Paul above and mine sounds like stock also.
TR6oldtimer has a comment above about the rockers hitting the VC because of the extra lift; he might be right!

 

[Brosky]

Graham,

I missed Ray's comment. That is entirely possible with the thicker aluminum cover and a crushed cork gasket under it.

That one is easy to check when you remove the cover and look underneath.

 

[tomshobby]

Bill, is there any chance that your rockers do not have enough clearance for movement? Or maybe the valve springs can not compress as far as needed?

 

[Brosky]

A lot of good thoughts here.

First question that I should have asked; does it make the noise with the cover either on or off? If it does it when off, that eliminates the arm hitting cover issue.

 

[Brosky]

Bill,

Any updates on this yet?

 

[Guest]

I'm in New Orleans working on my son's house. I would rather be home.