305 clacking noise
#1
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Car: 82 Trans Am
Engine: 305 LU5
Transmission: TH200c
305 clacking noise
Hi All,
This is my first post, but I've been lurking around here for over 15 years. This forum has helped me a lot with my car
I have an 82 Trans Am with a stock 305. I'm in the process of taking the heads off. There's at least a couple of valves that are bad, so I'm getting both heads rebuilt.
It has a noise at temperature when in idle. Tends to go away above 1000 RPM. I'm hoping it's a bad lifter or cam lobe which I think is caused or related to the bad valves.
Previously, I managed to stop it with Rislone Engine Treatment. But now the valves have gotten so bad I had to add valve additive to stop the spark plugs fouling. It's pretty thick stuff, some the clacking came back.
I've added an MP3 of the noise to this thread. Can you please listen to it and let me know what you think is causing it. I'm really hoping it's not a piston. It does sound a bit like piston slap. I want to be able to pull the heads and change the lifters and the cam without taking the engine out.
Any help will be appreciated,
Adam
This is my first post, but I've been lurking around here for over 15 years. This forum has helped me a lot with my car
I have an 82 Trans Am with a stock 305. I'm in the process of taking the heads off. There's at least a couple of valves that are bad, so I'm getting both heads rebuilt.
It has a noise at temperature when in idle. Tends to go away above 1000 RPM. I'm hoping it's a bad lifter or cam lobe which I think is caused or related to the bad valves.
Previously, I managed to stop it with Rislone Engine Treatment. But now the valves have gotten so bad I had to add valve additive to stop the spark plugs fouling. It's pretty thick stuff, some the clacking came back.
I've added an MP3 of the noise to this thread. Can you please listen to it and let me know what you think is causing it. I'm really hoping it's not a piston. It does sound a bit like piston slap. I want to be able to pull the heads and change the lifters and the cam without taking the engine out.
Any help will be appreciated,
Adam
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Car: 87 IROC L98
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Re: 305 clacking noise
Well if you are taking off the heads for rebuild, you might as well go one step farther and change the cam and lifters. A basic OEM replacement kit isn't that expensive. Your car probably has a lot of miles on it and the cam/lifters don't last forever.
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dmccain (04-11-2024)
#4
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Car: 82 Trans Am
Engine: 305 LU5
Transmission: TH200c
Re: 305 clacking noise
#5
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Car: 82 Trans Am
Engine: 305 LU5
Transmission: TH200c
Re: 305 clacking noise
Car's only done 67000 miles, so should've lasted longer.
Thanks for the advice, guys.
Adam
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