Valve Train Help!
Discussion
Trying to fix a tap/ rattle coming from the valve cover of my engine, now its a high mileage (122k miles) petrol motor.
The tapping is not loud enough to be heard inside the cabin, although between 2000 and 3000rpm, usually when changing gears i get a fairly loud rattle which i would assume happens as engine is not under load (off the throttle). I can get the engine to make the noise wether in or out of gear. its just most often heard as i change gear but seems more to do with the throttle body closing.
This engine is a bucket and shim type engine, and i understand how to measure the gap but what im confused about is when looking for parts i cant find any shims, just buckets of different lengths. I want to make sure I can source parts before attempting to repair as it may be more economical for me to just replace the head with a scrap yard head.
With the symptoms I have described does it sound more like a potential valve clearance issue or is it possible i have a broken rocker arm or valve spring? i know the engine was supposed to have had it valve clearances checked but I am unsure if anything was ever changed.
The tapping is not loud enough to be heard inside the cabin, although between 2000 and 3000rpm, usually when changing gears i get a fairly loud rattle which i would assume happens as engine is not under load (off the throttle). I can get the engine to make the noise wether in or out of gear. its just most often heard as i change gear but seems more to do with the throttle body closing.
This engine is a bucket and shim type engine, and i understand how to measure the gap but what im confused about is when looking for parts i cant find any shims, just buckets of different lengths. I want to make sure I can source parts before attempting to repair as it may be more economical for me to just replace the head with a scrap yard head.
With the symptoms I have described does it sound more like a potential valve clearance issue or is it possible i have a broken rocker arm or valve spring? i know the engine was supposed to have had it valve clearances checked but I am unsure if anything was ever changed.
I do apologise, i was hoping on some more generic responses first i guess!
Its a Z 16 XEP Engine commonly found in Astra's and Zafira's
Car is an 05 plate Astra, runs and drives fine, no misfires etc.
Sometimes when idling at lights there is a slight hesitation, similar to what happens when the cooling fan comes on and the revs drop while idling.
e2a: These are the buckets I can find http://catalogue.faiauto.com/parts/BFS276S#anchor
2nd e2a: This is a blown up diagram of the engine https://vauxhall.7zap.com/en/car/t98/e/7/26-0/
Its a Z 16 XEP Engine commonly found in Astra's and Zafira's
Car is an 05 plate Astra, runs and drives fine, no misfires etc.
Sometimes when idling at lights there is a slight hesitation, similar to what happens when the cooling fan comes on and the revs drop while idling.
e2a: These are the buckets I can find http://catalogue.faiauto.com/parts/BFS276S#anchor
2nd e2a: This is a blown up diagram of the engine https://vauxhall.7zap.com/en/car/t98/e/7/26-0/
Edited by SClark on Wednesday 7th August 15:38
Bucket & shim is a generic term that certain manufacturers apply in a different manner, it seems that you may have found one of theses.
The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
E-bmw said:
Bucket & shim is a generic term that certain manufacturers apply in a different manner, it seems that you may have found one of theses.
The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
This is what I was hoping, thanks for the help.The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
Am I correct in assuming its the buckets that wear? or is the cam lobes?
trickywoo said:
As others have said your description is pretty flaky. Could just as easily be a resonance rattle of a heat shield or something.
Im by no means a master mechanic but I can swing a spanner... Its not a heat shieldSClark said:
E-bmw said:
Bucket & shim is a generic term that certain manufacturers apply in a different manner, it seems that you may have found one of theses.
The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
This is what I was hoping, thanks for the help.The diagram shows different thickness buckets & the part you link to is one of those different sized buckets, so you have found the right part, I don't see what your confusion is.
As to whether that is the cause of your particular noise I/we cannot tell from here.
Am I correct in assuming its the buckets that wear? or is the cam lobes?
Checking the clearance on solid lifters is relatively simple for a home mechanic who can swing a spanner and you should measure and compare with manufacturers tolerances.
I was told on my Duratec engine it was the cam chain, replaced it and still had a tick, should have checked the bucket gaps first
I was told on my Duratec engine it was the cam chain, replaced it and still had a tick, should have checked the bucket gaps first
PaulKemp said:
Checking the clearance on solid lifters is relatively simple for a home mechanic who can swing a spanner and you should measure and compare with manufacturers tolerances.
I was told on my Duratec engine it was the cam chain, replaced it and still had a tick, should have checked the bucket gaps first
Thankfully I have one of the Vaux engines without a chain, can say I'm not looking forward to getting the cams out twice though! I was told on my Duratec engine it was the cam chain, replaced it and still had a tick, should have checked the bucket gaps first
Am I correct in thinking I should get new camshaft seals? I'll reuse old ones after measuring buckets and use new ones after replacing any potentially out of tolerance buckets.
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