Lea-Francis built a very fine twin cam pushrod four cylinder hemi engine, which in 1767 cc form was campaigned in the Connaught Grand Prix race cars of the late 40’s. However Lea Francis bought-in their gearboxes from Armstrong-Siddley, and in its way, it’s a very fine transmission, too. We have been tasked to overhaul a MkIV gearbox from a 2.5 litre LEAF, and fortunately it came with abundant spare parts which we are now sorting thru. BTW: I believe that the MKIII unit used double herringbone gears. I won’t digress on that topic here, but you can look it up.
The 2nd gear pictured above on the left came out of the 2.5 litre. It has beautiful dog teeth, which are the pointy ones on top that engage the sliding synchronizer hub to lock it to the TX mainshaft, but the beveled gear teeth are pitted. The gear on the right has very nice gear teeth, however the dog teeth are rounded off a lot more than we’d like to see, so we’ll dig a litle deeper in the spare parts bin. That’s Patrick’s sketch underneath them on our cast iron surface table.
Every so often someone brings us in a rubber bumper MGB with a complaint about heavy steering. This is usually the result of the engine mount brackets, which are different from chrome bumper cars, having sheared, and that drops the catalytic converter on top of the steering column. We once had one where a long period of subsequent use had cut a groove thru about half the diameter of the column, but no harm, no fault I guess.
We never drove the car, and the customer never complained, but Butch thought the front engine mount of this TD seemed a little soft and decided to dig a little deeper. That’s an engine mount bracket bolt hitting the steering column coupling flange. The fix was a new mount.
Back to the matter of those broken MGB motor mount brackets for a moment. It’s one of the few aspects (besides engine output) that didn’t get better on those cars thru evolution, even though it is probably tied to the engineering for the handful of V8-engined GT’s which were built ’73-’75. For years we kept two and a half sets of mount brackets on hand because almost every car we were seeing needed at least the left hand bracket, probably because of the torque load.
The current temperature is right around 20 degrees below zero (that’s fahrenheit if you’re reading this in a metric country), and January 25 was the last day it was above freezing. Right now our snow cover is approacking waist deep, but more is forecast later today so maybe we’ll get there. So glad we’re not in Boston where they’ve gotten seven feet over the last month.
Here’s a picture from last year courtesy of the Wishful Thinking Department: Butch out for a spring road test in a Sports Car Services prepaired (meaning very fast) Morgan +4. Spring’s coming, we hope.