To my other MGA pages.

April 13, 2025

Rear Springs

MGAs used a pair of semi-elliptic leaf springs as the rear suspension.  The basic design dates back to horse drawn carriages, but today has become all but obsolete for light passenger cars.  The springs attached directly to the solid rear axle.




I liberated the springs from the axle, and stripped some of the mounting paraphernalia.  At this point, I measured the spring height as 6.3 inches.  This suggests that the spring had somewhat relaxed from the stock height of 6.6 inches.  The difference didn't seem too serious to me.




Then separated the leaves.  This requires a brutish process of bending the legs of four heavy clamps.




Then, and equally brutish process removed the Silentblock bushings from the main leaves.




The spring leaves were pretty dirty and rusty, but a time under the blaster cleaned that right up.  There was definitely some wear marks where the ends of one leaf rubbed on the leaf above.  These were easy to see and feel, but measured at most around 0.020" deep, and didn't show any sharp corners that might encourage cracking.  I sanded the worst ones with a belt sander to try to level them, but finally decided it probably wasn't worthwhile. Bracketry got blasted, too




A coat of epoxy primer followed by a nice topcoat made the leaves a lot more presentable.  Brackets got powder coated because they fit into my oven.  U bolts and the pin that holds the leaves got zinc plated.




The shackles were in decent shape with just some minor pitting on the pins.  The pins got zinc plated to delay any further corrosion, and the plates got powder coated.  I got some fancy Urethane bushings




I opted to use some lining material between the leaves.  This is supposed to eliminate squeaking, and might reduce the chafing wear by the ends of the leaves.  I sprayed a light tack adhesive to keep the liners in place for assembly.




Before assembly, I relieved the sharp edges on the ends of the leaves that would contact the leaves above them.  I hoped this would help prevent wearing through the liners. 

It would have been an excellent idea to do this before the leaves were painted.




When the first four leaves are stacked, the clamp arms had to be bent back into position. 




Both springs assembled, ready for the new Silentbloc bushes.  It would have been much easier to install them before the leaves were stacked.  The springs weigh over 20 pounds apiece.




Then the shackles, so they don't get lost.




I located the rubber mounting pads.  These were new in my 70s work, and have very few miles on them.  They cleaned up really well, so I decided to re-use them.




Final assembly...




And, on the shelf with these dudes.




This was sort of a fun project.  It took some muscle in places, but nothing unmanageable.  Cost was around $60 for the liner material, bushes, and some consumables.

Comments to Ed at elhollin1@yahoo.com

To my other MGA pages.