Thumping under seat
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7th Gear
Joined: Jul 2022
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Thumping under seat
Hey again guys, I thought I fixed the problem, but apparently not. After my 79's warmed up, I feel a thumping sensation under my seat when stopped, in drive. I got a new distributor, cables, and had her timed since (about a month ago). I thought the problem dissipated, but I haven't really driven her much since, as I just got AC in her. Anyone have any idea what it could be? I took a look at the torque converter. And she's on tight and straight. I also have a problem where the motor putts once or twice after I cut it. Any help would be appreciated! Thank you gents!
-She's a 79 L48, original 350 small block and 3 speed automatic transmission
-She's a 79 L48, original 350 small block and 3 speed automatic transmission
Last edited by Micmabbit; Sep 5, 2022 at 07:58 PM.
Drifting
Joined: Dec 2020
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From: Central Florida
2024 Corvette of the Year Winner - Modified
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Hey again guys, I thought I fixed the problem, but apparently not. After my 79's warmed up, I feel a thumping sensation under my seat when stopped, in drive. I got a new distributor, cables, and had her timed since (about a month ago). I thought the problem dissipated, but I haven't really driven her much since, as I just got AC in her. Anyone have any idea what it could be? I took a look at the torque converter. And she's on tight and straight. I also have a problem where the motor putts once or twice after I cut it. Any help would be appreciated! Thank you gents!
-She's a 79 L48, original 350 small block and 3 speed automatic transmission
-She's a 79 L48, original 350 small block and 3 speed automatic transmission
Make sure it’s not happening when you first take off in drive. Does it go away easy you get some momentum and then come back after another stop?
Burning Brakes
Joined: Sep 2012
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From: St Louis
St. Jude Donor '13
I had a thumping noise that was driving me nuts! It was my battery cable slapping against the body & / or driveshaft. The mount that holds it in place above the driveshaft had come loose.
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7th Gear
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Right under seat. I would look at exhaust bracket at the rear transmission mount. Bad transmission mount, etc.
Have you been under this car and had a look??
Have you been under this car and had a look??
Drifting
Joined: Dec 2020
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2024 Corvette of the Year Winner - Modified
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Drifting
Joined: Dec 2020
Posts: 1,586
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From: Central Florida
2024 Corvette of the Year Winner - Modified
2023 C3 of the Year Winner - Modified
2021 C3 of the Year Finalist - Modified
Thread Starter
7th Gear
Joined: Jul 2022
Posts: 7
Likes: 1