Need Help: Strange Noises
aonewordname
07-05-2010, 10:33 AM
I own a 69 beetle. As I decelerate about 60% of the time, especially during turns, I hear thumping noises under the car. I cannot figure out what causes this or how to fix it. Do I simply need to oil some part of the chassis? Any advice would be appreciated!
denisond3
07-05-2010, 07:34 PM
Im going to guess, since I dont know for sure....
At the forward end of the transaxle, where the shfter rod attaches, the transaxle is supported by a rubber 'mount' that bolts to the bellypan. If this tears from old age, it might let the enigine/transaxle move around a little bit on deceleration. While decelerating, the engine would be misfiring, as the mixture is pretty uneven when the throttle is shut. The misfiring is what can let the engine rock on its mounts, and that front mount is one that gets a lot of stress from acceleration, and might tear.
The other thing that you might be hearing is the muffled sound of the after-firing. (Backfiring is when the explosion comes up through the carburetor, If it goes out the tailpipe, thats 'afterfiring'.
At the forward end of the transaxle, where the shfter rod attaches, the transaxle is supported by a rubber 'mount' that bolts to the bellypan. If this tears from old age, it might let the enigine/transaxle move around a little bit on deceleration. While decelerating, the engine would be misfiring, as the mixture is pretty uneven when the throttle is shut. The misfiring is what can let the engine rock on its mounts, and that front mount is one that gets a lot of stress from acceleration, and might tear.
The other thing that you might be hearing is the muffled sound of the after-firing. (Backfiring is when the explosion comes up through the carburetor, If it goes out the tailpipe, thats 'afterfiring'.
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