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Discussion Starter #1
Just had the entire engine rebuilt by a reputable machinist after I spun a rod bearing. Broke in cam, dumped 30w Brad penn oil. Put in 10-40. Was running great and all of a sudden this...
Any thoughts?
https://youtu.be/rnHECKmx_YE
 

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no sir

it sounds like several are just barely touching

the valve covers look alot lower than the stock chrome or factory painted ones...

less than 10 minutes and youlle know ...

and buying the next round of barley pops ......... I hope ...

easy place to investigate ...

is the noise coming from the valve cover ??

can you feel the tapping when it runs with your hand on the valve cover



Scott
 

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Discussion Starter #5 (Edited)
Hard to pinpoint the sound especially in a garage. No apparent marks under the cover. But like u said it could be a few just barely kissing the roof. I?ll setup some cardboard to catch oil and give it a whirl.
I pulled both belts to see if it was anything related up front but Nothing.

Edit: not the valve covers
 

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Personally can't hear the clicking, but it sounds to me like it is not running very smooth. Fresh gas? If it has sat for any length of time (just a couple weeks), todays ethanol gas goes bad real quick and picks up a lot of water. If you are running on bad gas, it'll run like crap. Next re-check your timing. Ticking can also be a bad exhaust gasket either at the head or where the pipe bolts up to the exhaust manifold. Check for this as well.
 

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Discussion Starter #7
Gas is about one week old. I will borrow a buddy and his timing light sometime next week. In the meantime I?ll check exhaust gaskets. Anyone else use these layered aluminum header gaskets?
Not looking forward to one bolt in particular on the passenger side...
 

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I listened to your video, but it's so short it was hard for me to pick up on the noise you're talking about. I think I may have heard two --- really high-pitched and almost "hissy", and another that wasn't constant, somewhat random, and much lower pitched. Was it one of those noises that you're concerned about?

A longer video - at least a minute - would be helpful.

A trick you can use: Take a long wooden rod (a cut-off section of broom handle works great). Put one end of it on various places on the engine and the other rounded end right up to your ear - touching. Keep moving around until you find the spot on the engine where the sound is obviously the loudest to figure out exactly where it's coming from. That should shed some light on things.

Bear
 

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Discussion Starter #9
Spring went out in the PCV valve hallelujah! Apparent a big cam can do this... is there a better valve than the PV679 that y’all are ordering?
 

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Spring went out in the PCV valve hallelujah! Apparent a big cam can do this... is there a better valve than the PV679 that y’all are ordering?
New one to me, never heard of a big cam affecting a PCV valve. Try a different brand like an ACDelco. You can go to your local store or check out RockAuto online as they carry several name brands including the ACDelco PCV valve and I've had good luck with their stuff. :thumbsup:
 

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Discussion Starter #11
New one to me, never heard of a big cam affecting a PCV valve. Try a different brand like an ACDelco. You can go to your local store or check out RockAuto online as they carry several name brands including the ACDelco PCV valve and I've had good luck with their stuff.
[/QUOTE]

That’s funny Jim, last night I went to O’reileys and picked up a pcv valve, took a look at it and thought “this looks like garbage”. Went to autozone and bought an Acdelco that looked much better. Popped it in last night and it works perfect, let’s see if it holds up.

Funny thing is about the noise, that aluminum valley pan amplified the sound of the failed valve 10X and made it a much “harder” sound. Learn something every day!
 

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Good deal. I try to get some things in better brands. ACDelco still seems of good quality. RockAuto had other brands which were cheaper and actually looked cheaper. For the price you are going to pay for something small like that, might as well go best.

I guess aluminum can transfer more sound like that. I have been told from a rear-end builder that those who go with aluminum driveshafts find out that they transfer a lot more noise which of course comes through the car/interior, so he told me to avoid them if noise was a consideration.
 
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