65 Corsa Vert rear suspension banging noise

[joewryan]

It occurs whenever I drive over the road reflectors. It's a loud banging, on the right side only. Checked the torque arm bushing bolt is tight, the shock mounts are tight and have the rubber on each side, and replaced the 4 strut rod bushings. Any ideas?

Joe

[bbodie52]

It could be a problem with the rear axle bearing, but I suspect a failing bearing would grind or squeak in normal driving.

Did you inspect the universal joints in the half-shaft on the noisy side? The needle bearings inside the u-joint cups may be rusty, dry and disintegrating, which could permit the cross to shift within the cups, causing a banging sound. If you find the universal joints to be in poor condition on one side, they are probably deteriorating from neglect on the other side too. If faulty, all should be replaced with new universal joints that include grease (zerk)( fittings to permit them to be lubricated periodically without disassembling the half shafts.

The universal joints in the rear axles are often neglected on Corvairs. Some have no grease fittings (zerk fittings), so those universal joints are less-likely to be lubricated periodically. They will likely be allowed to deteriorate even more than normal since greasing them requires disassembly. Once the small amount of grease in the bearing is washed away, the needle bearings begin to wear grooves in the cross, and eventually the needles begin to break and disintegrate. If your universal joints lack grease fittings, be sure to replace them with quality units and then grease them periodically with a grease gun.



Badly worn universal joints can produce a clunking sound — especially in turns — as the cross shifts within the needle bearing cup. That sound may telegraph and the sound source maybe difficult to identify. Universal joints often are neglected — especially if they don't have grease fittings to allow them to be lubricated regularly. I recommend you inspect yours.









While almost any new universal joint is likely strong enough for regular street duty. many suffer from neglect. Be sure to buy replacements that include a zerk (grease fitting) in the design, so that they can be lubricated regularly without requiring disassembly.

If possible, support parts suppliers like Clark's Corvair Parts when buying replacement parts. Local auto parts stores have enough customers already, but Corvair specialty suppliers only have you for a customer, and we need to support them with our orders!

(Of course, in the United Kingdom or other non-USA locations your shipping and tax issues are a different problem. But the need for grease fittings in your universal joints is still applicable).

http://www.corvair.com/user-cgi/catalog ... &page=179B


Part number C3463: HEAVY DUTY UNIVERSAL JOINT 60-64 TAKE 2, 65-69-TAKE 4

Weight: 1 lbs 0 oz
Catalog Page(s): 167,179B,OT-42
Price:
1 - 2 $ 12.85
3+ $ 10.95

http://www.corvair.com/user-cgi/catalog ... ge=OTTO-27


Part number C11425 (Other): PERFORMANCE HEAVY DUTY UNIVERSAL JOINT 60-64 TAKE 2, 65-69 TAKE 4

Weight: 1 lbs 0 oz
Catalog Page(s): 167,179B,OT-27(RM19),O T-42
Price:
1 - 2 $ 19.65
3+ $ 17.70

One thought — Your late model Corvair is a convertible, and as such it contains a body dampener (nicknamed "Cocktail Shakers") in each corner of the trunk and engine compartment that is bolted in-place. If loose, jarring the car when striking an object in the road could conceivably shake a loose body dampener and cause a banging sound as it shifts position...








http://corvaircenter.com/phorum/read.ph ... 366,384498

If you were to open one up, and please never do as they contain a large spring under tension, you would also find transmission fluid. The sole purpose is to reduce harmonic vibration inherent in the Corvair Convertible due to the uni-body construction. They also weigh approximately 26lbs each and bolt into the corners of each fender. If you were to drive your Corvair without them and lowered the top, the car would not be as stable as it would with them installed for the simple fact that the body flex exhibited in a Convertible would be transmitted to the windshield pillars. I was impressed with the difference they made once I installed them (in my car).

The reference material below may be helpful as you look for the cause of your problem in the back of your Corvair, and work through the repair process...