So.. new noise today and cant figure out if its an exhaust leak, a lifter or a some valve slapping or just time for an oil change..

|UPDATED|3/26/2012 2:52:16 PM (AZT)|/UPDATED|


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Exhaust leaks can certainly mimic a loose rocker arm(valve adjustment). If it has gotten worse over the past few days, I'd suspect an exhaust leak. First place to check would be the spot where the manifold meets up with the head pipe. On the drivers side, there is a doughnut gasket there, that has a lead covered wire mesh. The lead deteriorates over time, and the pipe can start with a small leak that gets louder. Once the lead is gone, or the doughnut is crushed, the joint there will be loose. Sometimes, you can get by with just tightening up the 3 nuts, but...that's a band-aid at best. On the passenger side is the heat riser valve. It sit flat against the manifold with an asbestos-type gasket that can burn out, and cause the same problem.

I can't see the video here(dial-up SUX!), but someone else may be able to give a better idea of the noise.
From the description of the valve in the heater hose, it is prolly the heater control valve....it opens/shuts to control the amount of hot coolant entering the heater core. It prolly has a vacuum hose on it?


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Joel Adams
C3VR Lifetime Member #56    
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Thanks...i should have mentioned the car has headers,, so not sure that applies. Already checked the bolts on the headers but have not done the collectors yet. Will check the exhaust gadgets too. Bodes not seem to get better when the engine gets warm. As for the heater control. I would assume its safe to move to a spot that will hide it better

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I have hooker headers on my '78 and the bolts do work loose occasionally.  When that happens I hear a ticking sound (no, not a bomb either).  But you have indicated that you have tightened those bolts.  Did you use a torque wrench?  My '78 had a loose intake manifold which caused the engine to suck up some oil and deposit it in the left rear cylinder.  I was always adding oil and it would tick when the oil level dropped BUT when the engine warmed up, that sound would go away.

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Warning: The surgeon general has declared that it is NOT unhealthy to smoke your competition AND I just discovered that my corvette is a hybred.  It burns gas and rubber! 

I have Hooker headers also, and they do lossen up at times at the head. Just had a loose bolt that I tightened up on Sat. Good luck with it.

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Lifetime Member #116
Dave's '82

   

Thanks.. mine does not seem to get any better as the engine gets warm...

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Might want to check gaskets between heads and headers, could be blowing out even if bolts are tight.

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DanT

Yeah...headers will eliminate my post above...except if they are loose at the head.
I watched/lissened to the vid just now. Hard for me to tell exactly what the noise is, I think I hear what may be a valve adjustment that is too tight. I dunno....
A tip that I have posted here many times before on header gaskets....if you're using the paper/asbestos type gaskets, soak them in water for about 4-5 minutes before installing them. That softens them a little, so when you tighten the bolts, the gaskets will deform a little, and the header flange will sink into the gasket, making a really nice seal. Once finished, run the engine to get the gaskets hot, and then retighten. Then let the engine sit until it is completely cooled down. This has worked for me on many header equipped engines...it's one of the kewl things I learned back in my younger days of drag racing.


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Joel Adams
C3VR Lifetime Member #56    
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Joel,

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Warning: The surgeon general has declared that it is NOT unhealthy to smoke your competition AND I just discovered that my corvette is a hybred.  It burns gas and rubber! 

Thanks.. will check the exhaust gaskets..

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Not to get off the topic but, I would advise against going with the gear drive timing. Had a good set of Pete Jackson gear drive gears in my 74 and ended up with problems with cam walk (did have timing cover with cam button) and idler gears rubbing timing cover. And as far as the sound, most people asked me if my power steering pump was bad. Only people that recognize the sound are hardcore racers.  

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DanT

Sheeez lead gaskets on one side of the motor and asbestos gasket on the other side better call in a haz-mat team for this one

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C3VR Lifetime Member #93
 

Thanks guys.. I got the receipts out from the guy I bought the car from and looks like they put in roller rockers and h.Lifters.. so may not be much to adjust..

Exhaust leak is problaby it

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It ended up being two rockers out of alignment...  a lot better now.. thanks everyone

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glad you got her fixed. 

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Brian - NCM Lifetime Member

73 coupe L48, Flat-top pistons, Performer RPM Heads, Crane Cam and roller rockers, Holley 650 vac sec. Performer intake,
3.55 gear BTO 200-4R trans,
Leather seats, Seatbelt Plus 3point seatbelts, Pioneer CD player
Magnaflow Exhuast System

      

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Joel Adams
C3VR Lifetime Member #56    
My Link


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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

if the rockers were out of alignment did you check the push rods, rockers, and RA studs for wear,  the push rods can and will go thru the top of the lifter and rockers. 

Checked it all out while I had the covers off.. all looked good.. thanks!!!!

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