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Discussion Starter #1
my engine has recently been making an odd noise and after talking with a few mechanics the consensus is that it is something with the valves and one of them threw out the term "valve rebuild" so im wondering wut exactly im getting myself into cost wise and wut exactly i would need to buy thats involved with that, owning this car is a learning experiance so any info would be awesome
 

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"Valve rebuild" and "valve Job" are the same thing.

You'll be removing the heads, grinding the valves and seats, repalacing the prings, retainers, and keepers. Some ov the valves may need replacement, too.

Better have the heads re-surfaced while you're at it.

Usually when an engine needs a valve job, it's silent. You lose performance and burn oil, but don't really make funny noises. What - exactly - is your car doing?
 

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its making sort of like a light slapping sound when it warms up and it follows with the RPM's, i was told to change the oil to a thicker oil cause my guy thought it might be because the oil was too thin but i changed it and no go.
 

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Usually you can isolate where the noise is coming from by taking a screwdriver, placing the blade on the area you think the sound is coming from, then put your ear on the handle. If the sound is coming from the valve covers, it's probably your valves or rocker arms. Your motor probably needs to be rebuilt anyways, though. New bearings, camshaft, rings, bored and honed, polish the crank, etc. A full, quality rebuild should run 3-5,000.
 

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now heres the kicker, i bought this car a month ago and the engine was rebuilt, under 30k miles on it so how possible is it that they rebuilt most of it but left the valves out of the rebuild
 

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That sounds unlikely. Maybe it wasn't broken in properly or something like that. Could be a collapsed lifter. Then again considering the recent rebuild, maybe one of the rocker arms is not tightened down far enough, causing just enouch slack to allow for some tapping sound everytime it's engaged by the pushrod.
 

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Get a reference book and adjust the valves to spec. How did this guy determine that you need a valve job? Did he do a compression and leak down test or any kind of testing at all or did he just hear the sound it was making? A valve job to correct a lifter noise sounds as if you need to find another mechanic. Valve jobs don't come cheap. Readjust the valves and see if the noise continues. If it does, a lifter may be bad and that's all.

I wouldn't keep a thick oil in the engine, go back to a 10W-30 and get an oil additive that contains zinc. The latest formulation of gasoline engine oils has most if not all of the zinc additive removed (Govt. emission reduction is the reason it's gone). The zinc is important for lubrication of a non-roller lifter (There is extreme pressure applied to the contact surfaces between the lifter and camshaft lobe) and a lot of lifter problems have surfaced because of this.

Oils that are formulated for Diesel and gas engine use still contains the zinc. For this reason I use Shell Rotella T in my flat lifter engines. Your problem may be rooted in scuffed lifters because of the oil and or when the engine was rebuilt, the lifters weren't properly broken in.

If you find that it's just one lifter making noise after adjustment, it may be just a bad lifter and that's all. Another problem that has surfaced lately is lifters that are being made off-shore. The metals that are being used to construct them is of an inferior quality and you can't tell by just looking at it when new. This is when it pays to spend a little extra money for a name brand lifter preferably made in USA.

I realize that you didn't have anything to do with what components were installed when the engine was rebuilt, but needing a valve job on an engine with the milage that you indicate sounds extreme to me. I wouldn't know why someone wouldn't have the heads done if they rebuilt the engine, it's part of the rebuild. Save your money and adjust the valves first and see what happens and get a second opinion if you need to.
 
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