Another week of little
progress, and yet somehow much to report. After all the work and problems of getting the donor
running, we put the M.G. aside for a while and got back to cutting metal. This of course is what
building a Locost is all about, not tinkering with 40-year-old motors. And fabricating parts puts a
thankful end to the slow and painful design process. The rear differential bracket, just one
example, went through dozens of design iterations because it's just way too easy to make changes
before the part is actually built.
Actual fabrication of the differential brackets
We had envisioned constructing differential brackets from 4"x 1-1/2" rectangular tubing, by
drilling holes and cutting the openings for the axle tubes with a hole saw, then finishing them off
by splitting the brackets down the center of the hole. Even today, we're shocked this actually
worked. The only problem is that the holes are a little small for the 2-1/2" axle tubes, because we
cut the holes with a 2-3/8" hole saw, because a 2-1/2" hole saw cuts 2-9/16" holes in metal. Why we
don't have the technology to make a 2-1/2" hole saw that cuts 2-1/2" holes is a mystery.
Practically ready to install
So the rear suspension is almost done, and looks great as shiny metal parts always do, at least
before welding. For the rear shock brackets we settled on something close to the book design. We're
cutting the top plates and the forward support gussets from a single piece of 2" square tube, and
the shock mount from a 1-1/2" length of 1-1/2" square tubing, to be mounted vertically on the top
plate. This limits the amount of welding needed, eliminates some dead weight, and gives us a
fraction of an inch more wheel travel than the book.
"Special" pickup brackets under construction
Also on the cutting board are the lower rear pickups for the front suspension, which have to be
angled five degrees on the bottom. We're still cutting with a Dremel, however we recently scored a
loan of an air-powered angle grinder, and we're anxious to give it a try. We still have a lot of
cutting to do for the engine mounts, steering rack mounts, radiator mounts, and possibly other
mounts, and we need to get started soon before the designs change. Plus, down the road we have to
cut the floor, firewalls, and bulkheads, so we're really counting on that grinder.
Semi-professional battery installation
The big news is, we drove the M.G. on Saturday. The fuel pump is finally in place and working
beautifully, i.e. not leaking, and the battery is now "installed" in a manner that allows it to be
carried along with the car. Unfortunately the car did not start immediately Saturday, or even after
one or two tries. It needed quite a bit of prodding, and only after half an hour of tinkering,
coaxing, testing, and cussing did it finally light up. It sounded great, though, and ran reasonably
well on at least three cylinders, and sometimes four.
Which was good enough for us, so we took the car for a short spin up and down theA block, and it
never completely died although it seemed determined to do so. The good news is, the clutch worked
perfectly and the gearbox felt excellent. Our M.G. experience includes only the early crash-bottom
boxes, which we now know were dangerously weak. This later model was really solid, with the 3-2
synchro still functioning, which is really amazing after all these years. And no whine or clunk, or
noise of any sort from the differential, a major bonus.
Amazingly, the brakes still work. Sort of.
Encouraged well beyond the bounds of common sense, we decided to coax the car into a longer
drive. We turned around and cruised on past the house, smiling and waving to the neighbors,
blipping the throttle as needed to keep the engine lit. We continued on down the street to the main
drag, where our first attempt to stop the car with the rusted brakes put us ten feet out into the
intersection. Cross traffic was light, so no harm, no foul. And the brakes did ultimately work,
they just needed a firmer foot on the pedal.
Up the boulevard we motored confidently, the engine alternating between hesitant and stopping
altogether, shifting up to fourth gear, gearbox slick as Teflon. The car felt great, the steering
quick and direct, the suspension firm and responsive. Even the seats were comfortable, resting
unbolted on our makeshift plywood floor. Despite the occasional loss of power, a dip of the
throttle would get things moving again, which allowed us to get a good mile from the house before
everything quit completely.
As sorry and miserable as it looks
We stood in the street and fussed with the ignition for quite a while before a neighbor took pity
and offered to drag us home with his pick-up truck and an old chain. Thankfully, the tow was
uneventful. For good measure we even let the truck haul us in gear with the ignition on, which
actually relit the engine, allowing us to pull into our driveway with a shred of dignity left. We
waved a thank you to the truck driver and he drove off, no doubt reasonably confident we wouldn't
sully his neighborhood again with our rusty old wreck.
We spent the rest of the afternoon diagnosing the ignition, testing every component and resetting
the dwell and timing. We got things working to the point where the car would start, but die within
10-15 seconds, every time. We were fairly certain the problem was no longer with the ignition,
which left the carburetors as the primary suspect, which was unfortunate because carburetion is one
of those mystery automotive technologies that you're never quite sure why it works and you
definitely never want to have to mess with. So we called it a day.
We did spend some time that evening researching SU carburetors online, and came away convinced
that we have a punctured float. Maybe even two punctured floats. These are easy to replace, which
makes them the ideal problem to have when your M.G. isn't running. The main symptom of a punctured
float is an extremely rich mixture, and we have that in spades. We pulled one of our brand new
spark plugs and found it completely black. Rich mixture. We also noticed a puddle of fuel on the
carb inlet, and were pleased to read that this is yet another symptom of a punctured float.
Our second best option would be a stuck metering valve. Or two stuck metering valves. Metering
valves stop the flow of fuel into the carbs when the floats indicate the fuel bowls are at the
correct level for the proper air-fuel mixture. The valves are only a little harder to replace than
floats, and when they stick they have the exact same symptoms as punctured floats. And old gas
makes things stick. So there's hope. All things considered, we're fairly certain we can get these
carburetors working without overhauling them completely.