What is an AC Engine?
Blocks, Studs & Water Jackets
Spare Parts List One - Attaching Parts, Seals & Gaskets
Spare Parts List Two -
Crankshaft & Cross-shaft Assemblies
Spare Parts List Three - Pistons & Liners
Spare Parts List Four - Sump Assembly
Spare Parts List
Five - Cylinder Head Assembly
Spare Parts List Six - Ignition,
Spare Parts List Seven - Water Pumps
Engines for Sale and
Rebuilds......Engine Rebuilds......Engine Rebuilds......
Restoring it to health
engine - dream or nightmare?
The venerable AC engine can
be a source of delight or a fount of frustration. Well fettled, it
is smooth, powerful and reliable. Neglected or bodged, it gives
endless trouble. Blocks and cylinder heads corrode and crack, head
studs snap, oil leaks past every seal, head gaskets fail and water gets
into the oil. Eventually the thing refuses to run at all.
It is at this point that
the unwary and perhaps still optimistic owner may lift his cylinder head
in the expectation of finding nothing worse than a blown gasket. He
may indeed find that but far more likely, he will also encounter a
depressing mess of rotten aluminium, rusty studs and a veritable dune of
silt rising from the base of the front cylinder to the top of the water
jacket space at the rear of the engine.
This where the owner, now
becoming seriously concerned, leans on the wings of his car and stares
into the engine bay with a sense of rising hopelessness. If he has
only recently bought the car, he now understands why it was for
sale. The sight of huge quantities of red sealant around, on and
under the head gasket provide evidence of the previous owner's desperate
attempts to solve the problem or at least to disguise it until the car was
safely out his care.
At this stage many owners,
convinced that the AC engine is inherently fragile and troublesome, give
up in despair.
So what does it
This is a perfectly
reasonable question. Unfortunately there is no easy answer as
final costs are, fairly obviously, based on the amount of work to be
undertaken. We therefore provide estimates based on best and worst
case scenarios for the job in question. We are not the cheapest on
the market but we are a long from being the most expensive. We are
always pleased to discuss an owner's requirement.
Please note that we
do NOT quote cheaply to land a commission and then, at the conclusion of
the exercise, cold bloodedly present the customer with a litany of
excuses to justify a grossly inflated bill e.g. 'We just had to do this,
that or the other...'. We do our best to keep the customer
informed of all challenges during a rebuild, especially any likely to
create unforeseeable extra expense.
A complete rebuild
During each engine
rebuild we e-mail the customer numerous written progress reports
supported by copious quantities of photographs, usually numbering around
100. These may be supplied on CD upon request.
Owners are welcome to
make an appointment to visit us to see how their engine rebuilds are
progressing and to take photographs of their own if they so wish.
They come in looking like this...
The things we
oil pump gears and screws caused by the engine standing for years with
water in the oil
Broken crankshafts. This is almost always
caused by abuse - the AC crankshaft is not inherently weak
up to it
No matter how
well made or maintained, all engines wear out eventually and will need
repair. The AC engine is no exception to this but its unique
features can mean that its design is often imperfectly understood.
This is an engine that cannot be treated just as any other, more
conventional engine and many highly experienced and competent engineers
have been known to either throw up their hands in horror when confronted
with an AC engine or proceed only to find themselves bogged down.
with the problems
as ownership can sometimes seem, most of the problems that afflict the AC
engine are merely those of old age. There was little wrong with the
original design - its 43 year production run speaks for itself.
Unfortunately, it is those very innovative features that give the engine
its uniqueness, notably the aluminium block and the wet liners, that lead
to the problems described. While there was a good supply of
reasonably priced second-hand engines in usable condition, it was possible
- and certainly cheaper - to replace than to repair. Unhappily,
engines so bought today are likely to be as troublesome as the ones they
are destined to replace. Even if running, such engines are very
likely to have been bodged to disguise the faults and all the the familiar
problems will reappear in a fairly short time. Experience has shown
that there is only one way to deal with an AC engine and that is
thoroughly. Half measures simply will not do. And this is
where we can help. And it need not cost the earth.
is not an option
up because the owner decides he has better things to do with his time and
money is one thing;
doing so out of despair is another entirely because there is not a problem that we
cannot solve one way or another. We have never had to admit defeat
yet and have brought many seemingly terminal cases back from the brink to
provide reliable service and driving pleasure to their owners!
Overhauling an Engine
The first essential to any
overhaul is to restore the block to sound
condition. It is a
complete waste of time carrying out any mechanical renovation unless the
block is perfect. We have seen many engines where this imperative
was ignored and with depressing and expensive consequences, usually
involving water getting into the oil and damaging the engine internals,
especially the bearings, devastating if they have have just been renewed.
your cylinder block has been restored, the rest of the engine can then be
overhauled as required. In association with our carefully selected
and proven suppliers we are able to provide the full range of overhaul
cleaning of engine components
testing of blocks, cranks, rods and heads
testing of heads
and line boring
of shell bearings on CL engines
of complete crank, damper, flywheel, pressure plate clutch assembly
machining and re-manufacture of broken parts
of stripped out threads
cleaning works wonders on the filthiest components
chemical cleaning, requisite machining and repairs, blocks and sumps are
scrubbed, pressure washed to remove swarf, air dried and inspected again
to ensure absolute cleanliness before re-assembly of the engine.
fitting, all moving parts are hand-operated to ensure correct movement and
freedom from binding and tight spots.
when it's done...
overhauled engines have the crucial block/head gasket/cylinder head joint
hydro-pneumatically pressure tested for leaks, the rear oil seal checked for leaks and are then
test run to ensure correct operation.
All engines are run for several hours and
any necessary adjustments made so that when an engine is installed in a
customer's car, it should start instantly and run well right from the
Head studs about to snap
Rotten, horrible blocks
Sumps full of sludge and bits of white metal
flywheels swimming in oil
Desperate bodges designed ......
Cracked cylinder heads
Disintegrating crankshaft dampers
Main bearings breaking up
Corroded cylinder heads
Worn out rollers
......to take up wear
Putting things right...
Oil seal conversion
Leak-testing ground in valves
Re-assembling damper flywheel
The picture to the left
shows a completely rebuilt engine following a successful test run and
awaiting collection by its owner.
Please note that the
engine is still fitted with our test set of carburettors with which we
normally run engines. We do not normally rebuild carburettors as
this is more cost- effectively undertaken by a specialist company but we
will be pleased to arrange this for you if required.
built by us have powered Frazer-Nashes on the gruelling 'raid' to Bolzano
including an ascent of the fearsome Stelvio Pass,
PVT ACs on long Continental tours and cars of all eras in numerous
competitive events including the taxing Mille Miglia on more than one