1953 4/4 4 Seater | Dave Sinclair - Poems, Prose and Morgans

Morgans - SNW545

Registration No: SNW 545
Chassis No: P2749
Year: 1953
Model: Plus 4 4 seater
Engine: Standard Vanguard, 2088 cc

Mileage: 04650

Wheelbase 96 in (2,438 mm)

Length145 in (3,683 mm)

Width 56 in (1,422 mm)

Height 52 in (1,321 mm)

Curb weight1,848 lb (838 kg)

Morgan had been making a two and four model called the 4/4 from 1936. In 1950 they introduced the Plus 4, using a 2088 Standard Vanguard engine. This model was announced at the 1950 Earls Court Motor Show and was built on a strengthened 4/4 chassis with a 4” longer wheelbase and using hydraulic drum brakes for the first time. Variants again included a 2-seater, a 4 seater and a Drop Head Coupe. w the design updated to improve aerodynamics and Morgan Plus 4s zoomed ahead, winning many sports car races. Just 141 cars were 4-seaters, 117 drophead coupes, the rest being 2-seaters in the 1950-53 period of production, with a large proportion retained for the UK market. 1954 saw the Standard Vanguard engine replaced by a 1998 TR2 unit (which retained the Standard Vanguard block) increasing the bhp from 68 to around 100 bhp and which replaced the flat radiator with a radiator behind a curved cowl. At introduction the plus 4 sold for £625 (two-seater) or £723 (coupé)

From the H&H auction site when I bought the car:

First seen in 1950, the Morgan Plus 4 was a larger and more powerful derivative of the company's 4/4 and has remained in production on and off for over 60 years now. Up until 1969 it was powered by the four-cylinder engines found in the Triumph TR range, which were mated to a four-speed manual gearbox with well-spaced ratios. The rakish body was mounted on a variant of Morgan's familiar Z section chassis, underslung at the rear. Suspension was independent by sliding pillars and coil springs at the front and a live axle on semi-elliptic springs at the rear. Braking was by drums all round and steering by a Burman cam and sector system. As tested by Autosport's John Bolster, the 100bhp 1991cc Triumph-engined Plus Four would accelerate to 60mph in 9.6 seconds and on to a top speed of a whisker under 105mph.

According to an accompanying 1989 letter from the then registrar, this delightful period Morgan was the only 'flat rad' four-seater Plus 4 known to the Morgan Sports Car Club at that time, so a decidedly rare version. It was purchased for £12,500 in September of the same year by the vendor's family trust, since when it has been continually maintained by renowned Morgan dealer Melvyn Rutter of Bishop's Stortford. The subject of a comprehensive older restoration just 4,543 miles ago, 'SNW 545' is smartly presented courtesy of Dark Green bodywork teamed with Black upholstery and carpets. Self-evident features of interest include the Bluemels steering wheel, quartet of period rear-view mirrors, rear-mounted luggage rack and radio aerial affixed to the left flank. The Morgan rides on silver-coloured steel disc wheels equipped with Avon HM Tourist tyres and highly polished hubcaps.

From Morganatica:

BACKGROUND

The Morgan Plus 4 was introduced in October 1950 using the engine developed by the Standard Motor Company for its Vanguard range of saloons and light commercials, which first hit the market in mid-1948. The engine was a wet sleeve design, and its bore and stroke, of 85 x 92mm, was almost square, and outside a fairly rigid UK engineering axiom for its car and motorcycle engine designs which effectively set strictures on the bore/long stroke relationship. This has prompted speculation on the inspiration for its design.

The engine was also used in the Triumph Renown, a version in the Ferguson tractor, and in upgraded form in the Triumph TR sports cars and the Vanguard Sportsman saloon.

The engine developed a reputation as a tough, reliable, durable unit. Factory data, for example, in outlining procedures for addressing oil pump wear states this is unlikely to be needed until approximately 200,000 miles have been covered.

As fitted to the Morgan Plus 4, the engine has some , largely cosmetic, modifications to its original specification. Principal are replacement of the air cleaner with a cap, a three degree cant for the carburetor compared to the 6 for the Vanguard, and modifications to the water pump and pulley.

CONSTRUCTION FEATURES

The block and cylinder head are of cast iron. The wet cylinder sleeves are centrifugally cast in nickel chrome iron. An advantage of this process is that it spreads the coarser particles to the outside of the sleeve, keeping the finer harder wearing particles on the inside of the bore.

The upper faces of the cylinder liners are flanged, with two pairs of flats at 90 degrees, enabling the sleeves to be rotated to address wear on the thrust face. The liners fit on a water seal provided by a composition packing which sits in a machined recess in the cylinder block..

The connecting rods are of molybdenum manganese steel with phosphor bronze gudgeon bushes. The crankshaft is forged from the same steel, and runs in three main bearings, thrust being taken from the centre main.

A cast iron camshaft with chilled cam faces runs in four journals. The front runs in a flanged cast iron bearing which also takes the camshaft end thrust. The other three journals run direct in the block, a practice carried over from the earlier 8/9/10 hp Flying Standard side valve engines, and in the Standard Special engine used in the later Series 1 Morgan 4/4’s. Interestingly, the Flying Standard 12 and 14hp engines did have camshaft bearing inserts and it is surprising that this feature was not carried over into the early Vanguard engine, although it did appear in some of its later manifestations. Of the camshaft, the Factory claimed : “The camshaft after grinding operations have been completed, is degreased, bonderised and, whilst still warm, immersed in a solution of “Dag” (Collodial Graphite). This process considerably improves the bearing surfaces and gives additional wearing properties”.

SPECIFICATIONS

Bore/stroke 85 x 92mm

Capacity 2088cc.

Power BHP 68 at 4,200 rpm

Torque 1,300 inch lbs at 2,000 rpm

Compression 6.7 to 1

Firing order 1,3,4,2 from front

Distributor Lucas DKY4A or DVX4A

Points gap 10 to 12 thou

Spark plug Champion L10, gap 30 to 32 thou.

Ignition timing 4 degrees BTDC at rest on 72 octane “pool petrol”. (Note: can be advanced with modern higher octane petrols. Best done by road testing)

Cam settings Inlet: open 10 degrees BTDC

close 50 degrees ABDC

Exhaust: open 50 degrees ABDC

close 10 degrees BTDC

Valve clearances 10 thou inlet, 12 thou exhaust.

Oil pump Horburn Eaton double rotor type. Rotor to cover plate clearance is 0.0005 to 0.00025” Clearance between rotors should not exceed 10 thou.

Carburettor Solex 32 B1O

Normal oil pressure 40 to 60 lbs

Oil capacity 12 pints (British) including filter

ENGINE INTERNALS

Crankshaft:

Main journals 2.479 to 2.4795” worn clearance allowance 0.006”

Big ends 2.0866” worn clearance allowance 0.006”

End float 0.004” to 0.006” , thrust washers on each side of centre

main bearing

Valves Inlet 1.5” head 5/16” shaft

Exhaust 1 9/32” head 5/16” shaft.

Valve spring sizes:

Inner free length 1.81” fitted length 1.31”

Fitted load 28lbs +2 lb -1 lb.

Outer free length 1.97” fitted length 1.63”

Fitted load 28lbs + 2 lb – 1 lb.

Also an extra small inner spring on the exhaust valve (some very early engines may not

not have this)

Valve location is by a collar and a slotted washer with overlapping offset holes of different sizes. In cases where the coils on the outer spring (unbound) tighten toward one end , this end goes to the bottom.

(NOTE: The inner springs are suitable for use on the Standard Special engine).

SERVICING/REPAIRING

Oil changes: Manufacturer recommends 3,000 mile intervals.

Recommended filter changes:

Tecalemit 10,000 miles

Fram 10,000 miles, but hinted at 6,000 to 8,000.

Purolator 8,000 miles.

Many cars now use an adaptor with a modern screw on filter. Given that the Plus 4 Morgan dispensed with an air cleaner, it is suggested that the oil and filter both be changed at 2,000 mile or six monthly intervals, whichever the sooner.

Torque settings;

Head bolts 60 to 65 lb ft (7/16” UNC high tensile) Exceeding this runs the risk of damaging the thread in the block.

Con rods 42 to 46 lb ft ( 3/8” UNF high tensile) The bolts are locked in place with locking tabs which form part of a metal strip spanning across the big end cap.

Mains 90 to 100 lb ft (1/2” UNC high tensile)

Flywheel 42 to 46 lb ft (3/8” UNF high tensile)

Timing wheel 24 t0 26 lb ft (5/16” UNC high tensile)

Manifold attachment 22 to 24 lb ft (3/8” UNC plus UNF stud, mild steel)

(NOTE: All high tensile are UTS 55 ton sq in min.)

Head tensioning sequence:

Right hand side

9 3 1 6 8

7 5 2 4 10

Tension progressively in four stages, ie 15 lb ft., 30 lb ft., 45 lb ft then 60 to 65 lb ft.

Removing/replacing cylinder head

Care is needed to avoid the cylinder liners moving and disturbing the bottom seal. Make sure not to rotate the crankshaft when lifting the head, and once off lock the sleeves in place. Retainers can be made by lengths of pipe to slide over the studs adjacent to each pair of cylinders, with a washer at the bottom overlapping the edges of each sleeve and at the top to allow the sleeve to be bolted up.

Manufacturer’s recommendation for fitting both the cylinder head gasket and the composition seal at the bottom of the sleeves is to use jointing compound only on the underside with light greasing of the upper.

Cylinder head gasket issues. With the old copper/asbestos gaskets now unavailable, the gaskets obtained from clubs or specialist suppliers/on special order are probably of a type which incorporated new material to substitute for the asbestos. This material tends to settle over time, and requires a special tensioning approach to compensate for this and prevent blowing. Typically, the head is tensioned, and the vehicle run for ten minutes then retensioned. It’s then taken on a run for around thirty miles and again retensioned. At 150 miles, retensioned again and finally again after 450 miles. Depending on the supplier there may be some variations to this procedure.

Replacing the crankshaft.

Ensuring the thrust bearings remain in place when fitting the crankshaft can be a bit tricky. The rear main bearing oil thrower and return has a feed back to the sump. This can easily become blocked if using silicone anywhere near this area, and oil will then ooze into the clutch housing. Take care.

PROBLEMS AND ISSUES WITH THIS ENGINE

Burnt Exhaust Valves. About on a par with other contemporary cars and a lot better than some, eg Morris 6 and Wolseley 6/80 vehicles. Not such a problem in an era when many owners carried out a decoke/valve grind almost as a routine maintenance item at 10 to 15,000 mile intervals or annually.

Crankshaft Breakage. Excessive end float could lead to crankshaft breakage, typically in the rear main bearing area.

Other Bearing Issues. Skimping on oil changes could lead to big end bearing failure.

Timing Chain Tensioner. The stud for the tensioner, can sometimes shear from its attachment point on the front engine bearer plate. Symptoms are that the engine will run smoothly with full power under load but misfire and run erratically on the overrun. The broken stud will generally be trapped in the locating collar on the tensioner and is unlikely to fall out and cause further damage.

Water Leaking Into Sump. Aside from the usual issues, a hard to find cause may be a small crack developing in the thread of one of the spark plug lands in the head, typically on number four cylinder.