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Valve train noise

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Old Jun 19, 2005 | 04:55 PM
  #1  
fauxrs2's Avatar
fauxrs2
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From: San diego ca
Default Valve train noise

Ok I installed a new flat tappet hydraulic in my car... over a month ago...Cali helped me on the break in....near the end of the breakin period we heard one or two clattering rockers and just wrote that off to the need to lash the valves again.

So I lashed the valves again....and again....and then I did a hot lash...and still when i run the engine for more than about 5 miles i start to get a loud valve clatter...so i cold lashed again... no joy....

So ive got this car which has been fighting me now for the better part of 6 months and its driving me batty - if its not one thing its another...

So Assume the following:

-Hydraulic flat tappet cam (basicly a 350hp/350 regrind)
-new 1.5:1 Roller rockers
-new lifters
-new pushrods

Broken in

Clatter in one or more rockers after warm-up.

I have one friend who says they need to be hot lashed again, because when the oil viscosity drops due to heat its allowing more slack in teh system...(frankly that sounds like a collpased lifter to me)

Anyway: What should i be looking for?

should i

a> lash it again (5th time !!!)
b> remove intake and inspect for collpased lifter?
c> replace all teh bloody lifters just to be safe?
d> sell this damned annoying car and get a mid-year?
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Old Jun 19, 2005 | 10:24 PM
  #2  
RAT502's Avatar
RAT502
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From: NorthRidge CA.
Default

Usually on a hydraulic cam you set lifter pre-load, not valve lash, when setting lifter pre-load turn the rocker nut while spinning the push rod with your fingers, when you feel slight resistance ( no play) turn the nut another 1/2 to 3/4 turn....
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Old Jun 19, 2005 | 11:46 PM
  #3  
cardo0's Avatar
cardo0
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From: Las Vegas - Just stop perpetuating myths please.
Default Locking nuts failed.

Sounds more like ur locking nuts no longer lock. And really lock nuts are designed for only 1 use - no reuse and expected to lock.

Now the real bad news, if uv'e been fighting this for 6mos then more than likely the cam lobes are hammered good and now junk (or soon to be) - lifters too.

Well don't feel so bad as i recently broke-in my cam too and while setting timing heard clicking increasing to a loud clack too. Pulled the vlv cover to find #3exh & #5intk rockers loose - #3 really loose and doubt if even touching vlv at full lift. But these were brand new #@x%*& Comp Cams lockng nuts that came with my CC Magnum tip roller rockers. I had even taken care to use my old rocker nuts while measuring p-rod length.

Since i have <1hr run time i'm gonna try and measure the #3 lobe and use it if ok. Already installed thin back-up nuts to double nut the rocker nuts. I use to do this double nutting when changing cams but not rockers but since i had brand new CC nuts i trusted them - much bigger than stock rocker nuts too.
But for u i would recommend at a minimum pulling the intk and measuring each lobe - if not then replacing cam & lifters after 6mos of hammering.

BTW did u use CC locking nuts? I emailed CC this weekend and waiting for reply before starting a wiped cam poll here - also need to find some time to measure my cam/#3exh lift.

Well i share ur pain. cardo0
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Old Jun 20, 2005 | 03:11 PM
  #4  
fauxrs2's Avatar
fauxrs2
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From: San diego ca
Default

Originally Posted by cardo0
Sounds more like ur locking nuts no longer lock. And really lock nuts are designed for only 1 use - no reuse and expected to lock.

Now the real bad news, if uv'e been fighting this for 6mos then more than likely the cam lobes are hammered good and now junk (or soon to be) - lifters too.

Well don't feel so bad as i recently broke-in my cam too and while setting timing heard clicking increasing to a loud clack too. Pulled the vlv cover to find #3exh & #5intk rockers loose - #3 really loose and doubt if even touching vlv at full lift. But these were brand new #@x%*& Comp Cams lockng nuts that came with my CC Magnum tip roller rockers. I had even taken care to use my old rocker nuts while measuring p-rod length.

Since i have <1hr run time i'm gonna try and measure the #3 lobe and use it if ok. Already installed thin back-up nuts to double nut the rocker nuts. I use to do this double nutting when changing cams but not rockers but since i had brand new CC nuts i trusted them - much bigger than stock rocker nuts too.
But for u i would recommend at a minimum pulling the intk and measuring each lobe - if not then replacing cam & lifters after 6mos of hammering.

BTW did u use CC locking nuts? I emailed CC this weekend and waiting for reply before starting a wiped cam poll here - also need to find some time to measure my cam/#3exh lift.

Well i share ur pain. cardo0
I havent been running the car, so there is probably less than 2 hours on the motor with this cam - the new cam has only been in for a month - the previous stuff is other issues ive been wrestling with.. so im fairly confident the cam is just fine..

Yes its lifter pre-load im talking aboout - I am running 1/2 turn past zero lash, and still getting clacking....in only one or two valves - and only after warmup.....

The locknuts on the roller rockers I'm sure are good for more than one use and in each resetting ive done they were well locked...
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Old Jun 20, 2005 | 04:10 PM
  #5  
ruby76's Avatar
ruby76
Drifting
 
Joined: Sep 2004
Posts: 1,532
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From: Fairview Heights Illinois, near Saint Louis MO, STL C3 Shark
Default

Now Im talking about a stock cam and stock lifters etc, but I had a 350 once that we adjusted preload and all, and it just always had a little valve noise on the driver's side. Ran great for 11 years after the rebuild. Is it REALLY loud? Also, my Ford ranger 4.0 liter has valve noise using 5w30 oil as per manufacturer specifications. When I run 10w40 there is no noise. So I run 10w40.
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Old Jun 20, 2005 | 04:57 PM
  #6  
Clint's C3's Avatar
Clint's C3
Burning Brakes
15 Year Member
 
Joined: Jun 2004
Posts: 1,012
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From: Granbury, TX
Default

Originally Posted by fauxrs2
I have one friend who says they need to be hot lashed again, because when the oil viscosity drops due to heat its allowing more slack in teh system...(frankly that sounds like a collpased lifter to me)
The viscosity drop could be allowing your lifters to bleed down slightly.

I had a mild tapping in my T/A after valve job, rocker arm and lifter swap. It only happened when the car was thoroughly warmed up. I adjusted the lifters several times and could not make it stop. I changed to Mobile 1 10/30 and added Lucas synthetic oil conditioner and it stopped tapping. Of course this would only work if your tapping is very mild.
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Old Jun 24, 2005 | 06:10 PM
  #7  
fauxrs2's Avatar
fauxrs2
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Drifting
 
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From: San diego ca
Default

Originally Posted by Clint's C3
The viscosity drop could be allowing your lifters to bleed down slightly.

I had a mild tapping in my T/A after valve job, rocker arm and lifter swap. It only happened when the car was thoroughly warmed up. I adjusted the lifters several times and could not make it stop. I changed to Mobile 1 10/30 and added Lucas synthetic oil conditioner and it stopped tapping. Of course this would only work if your tapping is very mild.
Im running stright 30 wt IIRC but I'll do an oil change and see if that changes anything...to me the tapping isnt all that mild...but i could just be paranoid
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