Rebuilding top of engine
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Joined: Apr 2009
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From: AZ
Rebuilding top of engine
05 350z. Top of the engine (valves, etc) are starting to sound metallic during idle.
How much does it cost to rebuild/swap out the top of the engine?
Nothing wrong with the block or anything like that
How much does it cost to rebuild/swap out the top of the engine?
Nothing wrong with the block or anything like that
Are you sure its the valves and not the timing chain attling on startup? What are the symptoms and conditions of when the noise happens?
To rebuild or replace the valves (heads) it is a very involved task. Front timing cover, all engine accessories, cams, all the timing and cam chains, intake and plenum all need to come off to get to the heads. Then removing the heads themselves with the engine in the car can be done, but its a tight job and not much fun.
It is quite an involved job.
To rebuild or replace the valves (heads) it is a very involved task. Front timing cover, all engine accessories, cams, all the timing and cam chains, intake and plenum all need to come off to get to the heads. Then removing the heads themselves with the engine in the car can be done, but its a tight job and not much fun.
It is quite an involved job.
Thread Starter
Registered User
Joined: Apr 2009
Posts: 18
Likes: 0
From: AZ
Are you sure its the valves and not the timing chain attling on startup? What are the symptoms and conditions of when the noise happens?
To rebuild or replace the valves (heads) it is a very involved task. Front timing cover, all engine accessories, cams, all the timing and cam chains, intake and plenum all need to come off to get to the heads. Then removing the heads themselves with the engine in the car can be done, but its a tight job and not much fun.
It is quite an involved job.
To rebuild or replace the valves (heads) it is a very involved task. Front timing cover, all engine accessories, cams, all the timing and cam chains, intake and plenum all need to come off to get to the heads. Then removing the heads themselves with the engine in the car can be done, but its a tight job and not much fun.
It is quite an involved job.
My engine sounds more "metallic" and not as crisp as it used to. This is prominantly heard when idling. While going through the gears, as long as the rpm is decent (>3k) it sounds good, no real "metallic" sound.
When you open the hood while it is idling, you can hear the "metallic" noise coming from the top of the block where the heads/valves and gaskets are.
My thinking is that during some of my tracking/sprinting, going into mid to high 6k rpms (have the redline max set at 6.8k), that I may have applied too much pressure and ruined a seal.
Finally, I'm not looking to do the fix myself, rather to take it in. Just wondering how much it would cost, and if I should just beef up the topend while I'm at it to maintain at least some value in doing it.
I think the stealership charges 2 grand for a valve job. My buddy just had his done by a mechanic friend and it was 3 nights worth of work. It's not that hard to take off the valve covers and check the clearances before you go sinking money into it.
remember a engine is metal and vibrates, it might sound like its coming from the heads but it can be something else, heck on some cars ive listened to it sounded like it was coming from the valves and it was the alternator. The only way to know for sure is a stetescope with a prob on it, or if you want the low tech way get a really long screw driver and put your ear up to it and place it on different parts of the engine. If its the valves it not going to be a seal, the seal only keeps oil out of the intake and exhuast track if you have a bad seal it will smoke on startup and then go away.
If its valve springs or valve guides the sound would get louder at higher rpms as the valves are moving faster and also the springs have less control due to harmonics and the increased force from increased speed. personally im thinking it might be the timing chain as i have seen them do this but im not sure of the physics on it and its more of a hunch then a yes this is it. i can tell you its 99% sure not the springs or guides though. and its 150% not the seals they dont control the valves at all
If its valve springs or valve guides the sound would get louder at higher rpms as the valves are moving faster and also the springs have less control due to harmonics and the increased force from increased speed. personally im thinking it might be the timing chain as i have seen them do this but im not sure of the physics on it and its more of a hunch then a yes this is it. i can tell you its 99% sure not the springs or guides though. and its 150% not the seals they dont control the valves at all
Eh, not sure but it's an educated thought.
My engine sounds more "metallic" and not as crisp as it used to. This is prominantly heard when idling. While going through the gears, as long as the rpm is decent (>3k) it sounds good, no real "metallic" sound.
When you open the hood while it is idling, you can hear the "metallic" noise coming from the top of the block where the heads/valves and gaskets are.
My thinking is that during some of my tracking/sprinting, going into mid to high 6k rpms (have the redline max set at 6.8k), that I may have applied too much pressure and ruined a seal.
Finally, I'm not looking to do the fix myself, rather to take it in. Just wondering how much it would cost, and if I should just beef up the topend while I'm at it to maintain at least some value in doing it.
My engine sounds more "metallic" and not as crisp as it used to. This is prominantly heard when idling. While going through the gears, as long as the rpm is decent (>3k) it sounds good, no real "metallic" sound.
When you open the hood while it is idling, you can hear the "metallic" noise coming from the top of the block where the heads/valves and gaskets are.
My thinking is that during some of my tracking/sprinting, going into mid to high 6k rpms (have the redline max set at 6.8k), that I may have applied too much pressure and ruined a seal.
Finally, I'm not looking to do the fix myself, rather to take it in. Just wondering how much it would cost, and if I should just beef up the topend while I'm at it to maintain at least some value in doing it.
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