Weird clacking sound from the valve cover
Thread Starter
Teching In
Joined: Dec 2018
Posts: 33
Likes: 8
Weird clacking sound from the valve cover I normally wouldn't post this because noise coming from under the valve cover is pretty obvious. This is different, it's not the normal clicking sound of a valve lash it make a clacking noise, sounds kind of hollow. I checked the valves... zero lash and they move side normally, so I went through the entire rocker arm adjustment again, setting them to 22.1 lbs. That did nothing, it seems to be over the # 3 cylinder. Anyone heard such a sound before, the only thing left is to pull the heads and replace the lifters... what else could it be?
I normally wouldn't post this because noise coming from under the valve cover is pretty obvious. This is different, it's not the normal clicking sound of a valve lash it make a clacking noise, sounds kind of hollow. I checked the valves... zero lash and they move side normally, so I went through the entire rocker arm adjustment again, setting them to 22.1 lbs. That did nothing, it seems to be over the # 3 cylinder. Anyone heard such a sound before, the only thing left is to pull the heads and replace the lifters... what else could it be?
Thread Starter
Teching In
Joined: Dec 2018
Posts: 33
Likes: 8
Possibly a broken valve spring? How loud is the "clacking?" Are you running dual springs? I've only broken one spring in my life, and it was LOUD!!! Sounded like some mean elf under the valve cover had a ball pein hammer!! I shut the motor down immediately. I'd say Gremlin, but hey, it's Christmas!!
Probably the lifter as G said, but check the straightness of the pushrods on that cylinder first. If there is the slightest bend in one of them, it will rub on the inside of the pushrod tunnel in the head and make an awful racket.
Also, check for a cracked insulator on the spark plug. It will “crack”or clank if it’s cracked. I’ve also seen exhaust leaks fool more than one mechanic into thinking there was a serious internal issue. Just a few places to check before you have to split it open. Fingers crossed here for ya.
Also, check for a cracked insulator on the spark plug. It will “crack”or clank if it’s cracked. I’ve also seen exhaust leaks fool more than one mechanic into thinking there was a serious internal issue. Just a few places to check before you have to split it open. Fingers crossed here for ya.
Thread Starter
Teching In
Joined: Dec 2018
Posts: 33
Likes: 8
Probably the lifter as G said, but check the straightness of the pushrods on that cylinder first. If there is the slightest bend in one of them, it will rub on the inside of the pushrod tunnel in the head and make an awful racket.
Also, check for a cracked insulator on the spark plug. It will “crack”or clank if it’s cracked. I’ve also seen exhaust leaks fool more than one mechanic into thinking there was a serious internal issue. Just a few places to check before you have to split it open. Fingers crossed here for ya.
Also, check for a cracked insulator on the spark plug. It will “crack”or clank if it’s cracked. I’ve also seen exhaust leaks fool more than one mechanic into thinking there was a serious internal issue. Just a few places to check before you have to split it open. Fingers crossed here for ya.
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Good calls above. One way I've found that usually works for exhaust leaks is to free rev the engine to maybe 1,500-2,000 rpm. Listen (or record-love technology-when it works, lol!) to the clicking. Then put the car in gear with either the foot brake or parking brake engaged, and increase the rpm/load on engine. If its a noticeable difference from free rev clicking, it's exhaust. Hope this helps......
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