A couple of years ago my gearbox had started making odd noises when accelerating under load, such as going uphill or accelerating “with vigor” as they say.  The noise was a kind of chattering, metallic sound.  Finally I decided to tackle a total rebuild of the drive line.  With the help of several AHCO members we removed the gearbox, overdrive, propeller shaft, and clutch.  We then dismantled everything, inspected each shaft, gear, thrust washer, bearing, oil seal, and replaced any component appearing worn or damaged.  We found the layshaft had been damaged by a caged bearing that had begun to crumble, several other worn bearings, and two of the three synchros appeared darkened by overhating.  Following reassembly of the overdrive we tested the hydraulic pump before mating the unit to the gearbox.  I then wrenched every nut, lock washer, bolt, stud, and fastener hardware multiple times to be sure they were tight.  Finally, the system got a fresh Healey engine green paint job and was re-installed in the car.

The initial drive was the June Club run to The Dalles.  Shifting was smooth as glass and the overdrive engaged with an impressive “kick in the butt” each time I threw the switch.  Of course after such a total rebuild I checked the system after each excursion.  And, of course, being a British system, it began to seep a little oil.  Only a British automotive engineer can make a solid block of metal leak oil.  But as time and mileage wore on the seep and occasional drip turned into an alarming amount of oil.  I wouldn’t go so far as to call it a hemorrhage but almost, i.e., about a quart of oil in the first 600-700 miles.  Obviously,  I had to do something.

Once I got the car back up on jack stands and the interior removed I started checking all the hardware to be sure all  fasteners were as tight as I had made them.  Now, here is today’s lesson and my reason for writing this little piece. Every nut, every bolt in the system required re-tightening!!!  Apparently, the initial running of the gearbox/overdrive, the heating-cooling-heating-cooling coupled with the vibrations causes the mating surfaces to settle in, the new gaskets to compress slightly.  Whatever the explanation, everything benefited from a re-wrenching about a month after the break-in of the rebuilt system.   After a complete rebuild of a Healey drive system I would strongly recommend checking the case work nuts and bolts for sufficient tightness.

Oh yeah, I did find my leak and fixed it.  I used florescent dye added to the gearbox oil to track down the specific leak in the system.  The process is simple.   One adds the 4 oz bottle of NAPA part number 765-2661 to the gearbox/overdrive oil, start the engine and engage 1st gear.  Recall, the car is elevated on stands so the rear wheels can turn freely.  Then with an ultraviolet light and in a darkend garage you scan the system for leaks.  I found my leak at the only bolt I hadn’t checked, i.e., the plug on the top of the overdrive operating valve.  While the engine was running and in gear there was a steady ooze of bright orange dyed oil from beneath the copper washer and bolt head on top of the operating valve.  One slight tightening of the bolt stopped the flow.  No other signs of leaks were detected and the Schneider Healey is “On the Road Again”.

One final thing,  I want to thank the John Carter, Gary Meyer and especially George Koeber for all the help and advice throughout theis project.  This is what a car club is all about.