Rebuilding Carburetors

Many British Cars are equipped with SU carburetors as is my MGA. This series of photographs shows some of the steps involved in rebuilding these carburetors. In the following photo, note the yellow arrow. This is pointing to the carburetor's fuel bowl vent/overflow pipes. If the fuel bowl overflows, which it sometimes does, then these small pipes are to drain the raw fuel safely onto the ground. However, some idiot has cut them off so that raw fuel will drain directly onto the very hot exhaust manifold. Naturaly I had to correct this mess.

This is what is inside. These are the old parts most of which were replaced with new parts.

These are all of the old parts cleaned and all of the new parts. Now, if I can just get everything back where it belongs.

Well, everything seems to fit OK. Note the repaired fuel vent/overflow pipe.

Here are the carbs back on the engine. Note the yellow arrow indicating the repaired fuel vent/overflow pipes. This is the proper termination so that fuel overflow goes safely onto the ground. Air cleaners installed. This completes the engine and it is ready to install in the frame.

Work Done as of January 2009

The following list is all of the work done on the car as of January, 2009. What is not included is the total cost to date. I don't even like to think about that.

1957 MGA FRAME OFF RESTORATION
Work done as of Jan 1, 2009

ENGINE, EXTERNAL: 1600cc engine
New motor mounts
New dipstick dust cap
New timing cover oil seal
Painted OEM red

ENGINE, INTERNAL:
Bought rebuilt 1600 cc engine short block:
New pistons and rings, standard
New rod bearings, standard
New main bearings, standard
New pushrods
New tappets
New timing chain
New flywheel ring gear
Flywheel resurfaced

OIL SYSTEM:
Spin on oil filter adapter and oil filter fitted

CYLINDER HEAD:
Rebuilt rocker assembly:
New rocker shaft
New shaft springs
New rocker bushings, drilled oil holes and reamed
Resurfaced rocker arms to remove valve stem wear indentations
Replaced OEM aluminum brackets with MGB cast iron.
New valve cover identity plates
New valve cover hold down rubber grommets, cupped washers, and distance piece
Cylinder head pressure tested
Cylinder head planed flat
New bronze valve guides
Valves and seats ground and new valve stem seals

COOLING SYSTEM:
New OEM sleeved thermostat
New fan belt
Radiator hot tanked and repaired
New radiator hoses and OEM clamps
New rubber packing strips
New drain tube
New radiator cap, 4lb

HEATER:
Heater core hot tanked and leak tested
New felt sealing strips applied to heater core
All heater parts sandblasted, primed and painted black
Heater motor commentator turned and new brushes installed
New rubber heater to body gasket
New heater water control valve

ENGINE CONTROLS:
All accelerator shaft-pedal parts and mounting brackets sandblasted, primed, and
painted black
New rubber accelerator pedal pad

AIR FILTERS / MANIFOLDS:
Exhaust manifold painted black with high temperature paint
Air filters sandblasted, primed and painted flat black
New OEM paper air filters and felt pads installed

CARBURETORS:
SU H4 carburetors completely rebuilt:
New jet lever return springs
New choke levers
New main jet, 0.90"
New jet needle, #6 for 1600 cc engine
New throttle shafts
New throttle shaft bushings installed
All new gaskets and washers
New Grose type needle valves

FUEL SYSTEM:
New SU solid state electric fuel pump
New rubber fuel pump mounting pads
New fuel pump to engine copper fuel line
New fuel tank
New fuel tank to fuel pump copper line
New fuel tank rubber mounting packing
New rubber hose and clamps, fuel tank to filler pipe
New ferrule, filler pipe to body
New rubber gasket, filler pipe to trunk floor

EXHAUST:
New stainless steel exhaust system
New exhaust pipe to exhaust manifold seal
New mid exhaust pipe hanger
New rear exhaust pipe hanger
New exhaust pipe clamps
New straps, long and short, exhaust pipe to exhaust manifold

CLUTCH:
Clutch-brake master cylinder relined with stainless steel liners
Master cylinder rebuilt with new rubber seals, gaskets, etc.
New clutch dry disk and pressure plate
New clutch throw out bearing, ball bearing type
New clutch lever arm bushing
New clutch slave cylinder rebuild kit
Clutch slave cylinder honed and rebuilt
New clutch slave cylinder hose with nut and washer
New clutch slave cylinder pushrod
New clutch slave cylinder rubber boots

GEARBOX:
Rebuilt with the following new parts:
All three baulk rings (synchromesh rings)
Layshaft bearings, all three
Layshaft
Input shaft ball bearing
Mainshaft ball bearing
Laygear front and rear thrust washers
All seals and gaskets
Rubber gearbox mount
Gearshift knob
Rubber shift boot
Clutch lever rubber boot

FRONT SUSPENSION:
New rubber rebound buffers
New lower "A" arm bushings, polyurethane
New swivel pin links bushings, pressed and reamed to 0.750"
New swivel pin links steel tube distance pieces
All new rubber seals, swivel pins and links
New link seal support plates
New thrust washers
New hub oil seals
New left hand thread hub spindle nut
New steering lever arm Nylock nuts
All exposed parts sand blasted, primed, and painted black

STEERING:
New steering shaft U-joint
New steering shaft upper and lower felt bushings
New tie rod ends
New steering rack rubber boot seals and clamps
New steering rack damper pad
New secondary rack damper pad
New pinion shaft seal
Steering wheel leather cover
New steering wheel center piece and clips
All exposed parts sandblasted, primed and painted

REAR AXLE:
To be done

REAR SUSPENSION & DRIVE SHAFT:
New rubber bumpers on frame
New axle travel limiting straps
New spring pad set, polyurethane
New front and rear spring bushings, polyurethane
Springs, shock links, etc., sand blasted, primed, and painted black
New drive shaft front and rear U-joints

BRAKE CONTROLS:
New clutch and brake pedal bushings
New clutch and brake pedal rubber pads
Master cylinder bored and relined with stainless steel liners
Master cylinder rebuilt with new seals and gaskets
New rubber gaskets on right blanking plate
New rubber pedal dust and draft excluder
All exposed master cylinder parts sandblasted and clear coated
All brackets and pedals sandblasted, primed and painted black

BRAKES:
Front brakes are disk brakes:
Calipers were disassembled and rust removed in Evaporust solution
New MGB pistons fitted
New piston seals installed
New fluid channel O-ring installed between caliper halves
New brake pads installed
New pad retainer pins and spring plates installed
Finished calipers painted red with caliper paint
Brake rotors sandblasted and non-braking surfaces primed and painted black

BRAKE PIPES:
All brake pipes replaced with new steel pipes and fittings
Front and rear flexible brake hoses replaced with new

HANDBRAKE:
New bushings installed
Fulcrum lever sandblasted, primed, and painted black

FLOORS:
All floorboards and toe boards redone in ½" plywood, painted with 3 coats of wood preservative and finish coat of flat black
Drive shaft tunnels rust cut out and 18 gage steel fitted and welded in
Drive shaft tunnels sandblasted, primed, and painted black

CHASSIS:
Car frame had all rusted areas cut out and new 16 gauge steel fitted and welded in
New rear corner pieces and tail board supports welded in
New drivers side front floorboard support welded in
Dented front cross member rounded out with 125 psi air pressure and heating torch.
Frame was sandblasted, primed with two coats of ZeroRust primer and two coats of black top coating

FRONT BUMPER:
To be done

REAR BUMPER:

FRONT BODY FITTINGS:

GRILLE:

REAR BODY FITTINGS:

BODY PANELS, OUTER:

BODY PANELS, INNER:

WINDSHIELD:

DOORS:

IGNITION:
Distributor: new points and condenser, Lucus

WIPERS:

LAMPS:

ELECTRICAL:
New starter switch

STARTER & GENERATOR:
Starter:
New pinion drive gear assembly
New front and rear bushings
Commutator turned
New brushes and springs
Generator:
Commutator turned
New brushes
New front bearing
New rear bushing
Both starter and generator sandblasted, primed, and painted black

DASH:
Dashboard sandblasted and primed

COCKPIT FITTINGS:

TOP:

SEATS:
Seat frames rust repaired by welding in new steel tubing
Seat frames sandblasted, primed, and painted black
New seat bases built from ½" plywood, coated with 3 coats of wood preservative and one coat of flat black paint.
Seat base steel perforated supports sandblasted, primed, and painted black

The Finished Car. When?

So, when is this car going to be finished? That is something I ask myself every day. I guess the answer is it is finished when it is finished. So, these pictures show where I am as of Oct. 18, 2008. However, what is not shown here is a basement full of finished parts ready to go on. The next major project is to rebuild the gear box. When that is finished, most of the mechanical aspects of the car will come together. Then there is the body work to do.

Fuel System

I tried to use the original gas tank but it was badly dented and rusted, New gas tanks aren't too expensive so I opted for a new tank. Only one of the straps that support the gas tank was whole, though, like everything else, badly rusted. As shown below, the other strap had the lower half missing. I cut a new strip from 18 gage sheet metal and welded it in.

The car came with a rubber hose connected from the gas tank to the fuel pump, which was missing. Because of this, I had no idea how the gas line was routed from the tank to the fuel pump. I thought it ran inside the frame. Wrong! At the Minter Gardens Car Show I crawled under every MGA there to see how to fit the gas line. It runs outside the frame as shown here. The fuel pump is a new solid state model of the original SU electric pump. No sticking points to worry about now.

The Engine

The engine is the most expensive part of the car to rebuild. Fortunately, I was able to buy a rebuilt 1600 cc short block from Geoff Pickard. This saved me a lot of money and work. I chased down a rebuilt cylinder head on ebay for a song. The rockers were rebuilt with a new shaft, rebushing and reaming the rocker arms (Fortin's again), and replacing the aluminium support brackets with MGB cast iron ones. Other parts were purchased to rebuild the generator and distributor. The generator was tested for shorts and then all new bushings and bearings installed. The commutator was turned, and new brushes installed. The distributor had new points, rotor, cap, spark plug wires, and spark plugs installed. The timing was set to ten degrees advance BTDC.

Front Suspension

There is a lot to do when rebuilding the MG front suspension. All of the rubber bushings were replaced with modern polyurethane bushings. All rubber seals were replaced. All of the trunion (link) bushings were replaced and reamed to fit (done by Fortin's machine shop). All other points of wear were replaced. The wheel hub bearings were cleaned, checked for wear, and repacked with grease. Everything was cleaned, sandblasted, and painted.

Steering Rack

MG uses a rack and pinion type of steering. There are very few parts that wear in the steering rack. Unfortunately, the factory used a grease fitting (a zerk) for filling the steering rack with 90W gear oil. I say unfortunately because service garages who do not know MG cars and see the zerk will fill the rack with grease. This a no-no as the rack does not receive proper lubrication filled with grease. Mine was, of course, packed with grease. Because of this, I had to tear it down to wash out the grease. After installing new rubber gaiters, I filled the rack with the proper gear oil.

Heater Rebuild

I like rebuilding parts like the heater shown here. This is because I can do the rebuilding in the workshop in dead of winter. I was stripping body parts off in January and had to heat my tools in the propane heater before I could hold them.