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-- Scuttle Shake --
I agree with John,
The Healeys as originally designed & built were not very prone to this problem. On old cars, & they are all old, the problem is made much worse by incomplete or poorly done "restorations" of rust damage. The cars are a semi unibody construction except that the skin carries very little load. They rely on the effective cross bracing of upper chassis parts to prevent flexing. All frame & upper chassis parts are welded into a single rigid structure. The body panels are just hung on the chassis & contribute little to the overall car rigidity. All metal under the skin must be repaired to original condition. (All metal in the frame & sub frame) firewalls, foot wells, scuttle, bulkheads , transmission tunnel, & related supports.
Cosmetic only restorations, & there are a lot of them, leave the rust damaged under structure weak & prone to extra vibration & "scuttle shake". I have seen restorations where the door gaps were closed at the top & considerably more open at the bottom. A sure sign that the chassis/frame is sagged in the middle. Usually due to excess flexibility caused by unrepaired rust damage in the under (hidden) parts.
One very good clue to a correct, complete restoration is being able to jack the car up at any single point & not have any door gap or panel alignment changes. I have seen some high dollar restorations where jacking a single point would cause The door gaps to change, hood & trunk lid going out of alignment to the point of binding.
If you want an old car to work as well as it did when new, everything, all parts, have to be in new condition. I have driven several Healeys when they were new or near new & they were very solid cars. "Drives like a new car" requires a new car.
Obviously very out of balance rotating parts will cause shake no matter how good the car is structurally. Some Healeys had/have a problem with the brake drums being way out of balance which needs to be addressed by correcting the drums independently of balancing tires & wheels. Worn suspension joints & bad shocks will contribute to the problem.
D
I agree with John,
The Healeys as originally designed & built were not very prone to this problem. On old cars, & they are all old, the problem is made much worse by incomplete or poorly done "restorations" of rust damage. The cars are a semi unibody construction except that the skin carries very little load. They rely on the effective cross bracing of upper chassis parts to prevent flexing. All frame & upper chassis parts are welded into a single rigid structure. The body panels are just hung on the chassis & contribute little to the overall car rigidity. All metal under the skin must be repaired to original condition. (All metal in the frame & sub frame) firewalls, foot wells, scuttle, bulkheads , transmission tunnel, & related supports.
Cosmetic only restorations, & there are a lot of them, leave the rust damaged under structure weak & prone to extra vibration & "scuttle shake". I have seen restorations where the door gaps were closed at the top & considerably more open at the bottom. A sure sign that the chassis/frame is sagged in the middle. Usually due to excess flexibility caused by unrepaired rust damage in the under (hidden) parts.
One very good clue to a correct, complete restoration is being able to jack the car up at any single point & not have any door gap or panel alignment changes. I have seen some high dollar restorations where jacking a single point would cause The door gaps to change, hood & trunk lid going out of alignment to the point of binding.
If you want an old car to work as well as it did when new, everything, all parts, have to be in new condition. I have driven several Healeys when they were new or near new & they were very solid cars. "Drives like a new car" requires a new car.
Obviously very out of balance rotating parts will cause shake no matter how good the car is structurally. Some Healeys had/have a problem with the brake drums being way out of balance which needs to be addressed by correcting the drums independently of balancing tires & wheels. Worn suspension joints & bad shocks will contribute to the problem.
D