AC 2 Litre Engine
Our engine comes from a non-matching numbers AC 2.0 Litre car. At some point, the 2.0 litre had the original engine replaced with the engine that was in it when we bought it. Our engine is one of the nine missing numbered engines that are listed in factory records and has a 'D' suffix. It is considered by the marque expert that this is a 'Development' engine for when AC were testing different white metal shell bearings that were used in the AC Ace. Our engine has a UMB number like the First AC Aces.
The picture below are the engine and chassis numbers showing the 'D' suffix for 'Development'. 'W' stands for 'Wellworthy Pistons'
From marque expert
"The engine you now have UMB1692W D is I a replacement block almost certainly fitted at the factory. D stands for Development. W stands for Wellworthy pistons. It would have been an AC development engine for the AC Ace. Around this time AC's were trying shell bearing big ends also a change to shell main bearings, these modifications came into production for the ACE, but must have been tested beforehand."
Picture son the right shows the ark with the matching number 1692 to engine UMB 1692 WD
Picture on the left shows the 10 missing engines from AC Records between 1689 and 1699 between cars EL 1688 and consecutive vehicle EL1689. Our number would be missing engine number 4 that was stamped 'D' for Development purposes at the AC Factory
Removal from the AC 2.0 Litre
To take the engine and gearbox out took 6 hours. You can see detailed pictures of the removal here: Our Ac 2.0 litre. Below are some pictures of the engine once it was removed. Love the look - there are AC logos all over the place! There is a small time-lapse video on the left. The cameras ran out of power before the engine was liberated.
Exhaust Manifold engine plates
Many thanks to Michael Beresford for passing on these superbly engineered plates for our AC Ace project 2.0 Litre AC engine. They fitted like a glove on dry fit.
AC Ace Exhaust.
On the right you can see an exhaust from an AC Buckland. You'll see the exhaust plates used that mate to the pipes. I reckon you could make this exhaust manifold without having to weld on the bends to get a much smoother look to the exhaust. It is a very visible item in the engine bay.
A dynamo bracket has to be created to move the dynamo to the front of the engine. Chatting to Rod Briggs, the AC 6 engine expert, he said that these parts are very simple and any machine shop should be able make them for you if you cannot do so yourself. The dynamo housing cover can be made out of a piece of 1/8" aluminium (or thereabouts) from a paper pattern. Rod kindly donated the sketch below. If you have any AC-6 questions or ends, Rod is your man and can be contacted at www.ac-6.co.uk 01458 273476
Engine mounts and Engine Mount Rubbers
The pictures below show the AC engine mounts and the contact details are where you can buy new AC engine mounts.
Ac Ace 2 bolt engine mounts
The picture on the left shows the Ac Ace 2 bolt engine mounts. These were supplied by Rod Briggs. I need to get good pictures from an Ace to finally decide on how we will mount our engine and what chassis brackets will need fabricating to keep it all as authentic as possible. Great find though and thanks to Rod we now have a couple of mounts that are very serviceable.
Above: AC 2 bolt engine mounts in situ in an ACECA
Another engine gallery
Pictures below show our AC engine before we stripped off the carbs and got it ready for the rebuild. The engine was photographed by Rana Dias in its as found state as it looks amazing with the oil and dirt all over it. It is amazingly clean underneath the muck!
Transporting the AC Engine
Cleaning everything up on the Ac engine
AC ACE Thermostat Housing
The housing is not so bad but our housing cap is shocking. It has been welded multiple times. I was chatting to a chap on eBay to see if he had one and he said "Why don't I cast one for you?" Well, never look a gift horse in the mouth. Des made a pattern and his dog chewed it up so he made a second one. You can see it here in the pictures on the right.
Below there is a gallery of the casting process. As Des works in the open air for safety the weather in West Wales doesn't help. This was first casting for thirty years or so, Des was quite pleased with it, although he will be remelting and recasting.
First 2 pics are straight out of the mould, the others after roughly removing extraneous extrusions.
The black stuff in the first pics is the core mould.
This is made from sand & oil and baked hard to ensure stability and no moisture. Any moisture would turn to steam when hit with molten aluminium (1300F) and be a bit dodgy as it blows everything apart! The orange peel effect is probably because the the melt contained hydrogen, so Des will degas the next time. It takes practice (and memory!) to get it right, but Des is getting there!
Des finds the original AC Engine Thermostat housing.
Des who kindly started casting the thermostat housing found his original one in the garage and sent it to me free of charge. Top man! As you can see the housing has cracked off sound the bolt hole and a large piece is missing from the inside. The piece inside may affect how the thermostat seals. The bolt hole might affect how the seal works and potentially let coolant escape. Right now I am looking at the options for fixing this up to get it 100%.
Thermostat housing and cap complete.
Brian of AC Spares has the thermostat housing cap. My housing is not in too bad condition. A little corroded but very useable.
AC 2 Litre engine at 'CCK Historic'
Our Ac works engine finally made it to 'CCK Historic' for rebuild. CCK have built engines for me in the past and their work is superb. You can see my trailer for transporting engines and gearboxes. After a mishap in an emergency stop, where a TR engine flew off a trailer on to the road and I had to pick it up and get it back on with my bare hands - I took precautions and built this trailer to take engines and gearboxes where they get locked in place so they can't move. This system works well.
Seals and Gaskets for Complete Engine
Exhaust Gaskets, pair
Oil filter housing, copper/asbestos substitute
Fig-of-8 gaskets 10 thou (0.25mm) or 16 thou (0.40mm) x set of 3
Fig-of-8 Set Halite/ali/paper gaskets for original short AC liners
Oil pump gasket, inner
Oil pump gasket, outer
Carb Gasket x set 3
Distributor housing gasket
Rev counter drive gasket
Sump gasket pair
CL oil gauze gasket
Head gasket copper/asbestos substitute
Rear crank seals pair
Rear crank seal set consisting of one piece lip seal, two seal carrier halves and retaining screws. Modification to block, sump and crankshaft required
PVT front seal carrier, ali
Sump plug gasket, copper/asbestos substitute
Studs, Bolts, Screws, Nuts and Washers for Sump
3/8" BSF bolts 4" post-war sump/block
3/8" BSF bolts x 11/4" block/sump
3/8" BSF Bolts 2" front block/sump
3/8" spring washer
3/8" BSF nuts, block to sump
3/8" BSF x 11/2" stud, block to sump
3/8" heavy washer
Replacement CL sump plug, hex larger head
Parts for Sump
Post-war oil pump, uprated, helical, suitable for all UMB and CL engines
Post-war oil pump, traditional type, suitable for all UMB and CL engines
Vintage & PVT oil pump, double instead of single rotor bearings
Oil pump drive shaft
Oil pump drive shaft gear
Oil pressure relief Valve, PVT
Oil pressure relief Valve, post-war
Relief valve spring
Relief valve ball
Crankshaft, billet steel, replacement for original for high performance engines, flangeless rear, requires special flywheel or adaptor to AC flywheel. Special order only.
Rear of AC crank (crankshaft adaptor), either flanged AC or flangeless type (latter requires special flywheel)
PVT end thrust adjuster
Shells for CL 1-4 mains bearings, substitutes for AC originals, modification required to shells and housings
Shells for CL No 5 mains, substitutes for AC originals, modification required to shells and housings
CL thrust bearing pair
Tab washer rear crank nut, all cranks
Tab washer front crank nut, late UMB and CL
Vintage crank sprocket
Bolt/starter dog late UMB and CL crank
Front damper for PVT/Vintage crank
Front damper for late UMB and CL
Aluminium front pulley for Ace/Aceca fan
Front crank pulley Ace/Aceca
Front crank pulley PVT/Vintage
Crankshaft skew gear, cross-shaft and oil pump drive gear set
Release bearing, all engines except vintage, exchange
Pressure plate, all engines except vintage, exchange
Friction plate, all engines, exchange
Vintage clutch plates, laser cut
Vintage clutch friction parts
Vintage clutch alignment bearing
Clutch master cylinder Ace/ Aceca
Clutch to flywheel bolts and washers
Camshaft, fast road
Rocker Shaft & Rocker Assy
Rocker shaft, extended at front for better location
Rollers with pins, narrow and wide
Rocker (mousetrap) springs
Rockers, uprated, investment castings completely fitted out with rollers and adjusters
Shim washers 0.858" x 0.630" x 0.020" and 0.040" rocker shaft
Vintage rocker cover
Cast iron, honed bore for smooth operation
Water Pumps & Thermostats
Post war, exchange, rebuilt and completely redesigned pumps, double bearings and modern seal
New PVT pumps
Thermostat, post-war, fits straight into housing with no adaptor ring
Distributor driven gear with pin and circlip
Distributor housing bearing
Post War Distributor DX
Rebuilt distributor or p-ex.
HT Lead 4.5 metre length
Distributor cap Lucas No. 407043
Points post-war for DX, replaces Lucas - DSB122C 407050
Spark plugs 14mm, various types
Studs, Bolts, Screws, Nuts and Washers for Block
3/8" head studs - short or long
3/8" head nuts
7/16" x 41/2" BSF stud, main bearing
7/16" x 41/2" BSF bolt, main bearing
7/16" BSF nuts, main bearings
7/16" twin tab washers, main bearing
7/16" round lockwashers (original type) main bearings
7/16" plain washers
5/16" twin tab washers, oil gallery
3/8" twin tab washer, oil gallery
5/16" x 23/8" stud, water pump, long
5/16" x 11/4" BSF stud, distributor mounting
1/4"W x 1" stud, timing wheel and fan
3/8" BSF x 13/4"stud, dynamo
5/16" x 1" BSF stud, oil pump cover
5/16" BSF exhaust studs long, PVT, Two Litre Saloon and Buckland
5/16" BSF exhaust studs short, Ace and Aceca
5/16" BSF brass nuts exhaust manifold
5/16" BSF water pump stud, long
5/16" BSF x 11/4" stud, water pump, short
3/8" BSF nuts, dynamo
5/16" BSF nuts, general
5/16" special bolts crank to flywheel
1/4" Whit. nuts, timing wheel and fan
5/16" BSF x 17/16" stud, bell housing
5/16" BSF bolts, bell housing
Nuts, spring and plain washers to suit all above
Parts for Cylinder Block
Water jacket casting
Camshaft oil jet
PVT front seal holder
Timing sprocket support
HT clips, screw and washers, post-war
Cylinder Liners and Pistons
Liners, longer than standard in body, require only single 10 thou fig-of-8 gaskets to set correct protrusion (in unmolested block)
Pistons, HC (replacements for original AC HC type) inc. rings and pins, weight - matched sets (2gms or less)
Forged pistons, extra high compression
Piston rings for original AC pistons, old stock, sometimes available
Rods, billet steel, replacement for original for high performance engines, complete with big end bolts and small end bushes. Special order only.
Small end bushes
Big end nuts and bolts 5/16" UNF for AC UMB and CL rods
Shells for CL rods, substitutes for AC originals, modification required to shells and housings
Flywheel for AC crankshaft
Flywheel for billet steel crankshaft
Rubber rings for AC damper flywheel
Crankshaft to flywheel special bolts, nuts and washers
Cross-shaft Spindle & Gear
Shroud as repaired
Remote filter assembly, consisting of filter header, swivelling connectors for universal application, sealing washers, unions, rubber piping and clips
Camshaft shell bearings for use when originals worn
Rocker & camshaft pedestals, new castings pilot machined
Camshaft Studs and Nuts
Camshaft/Rocker Cover Studs, long, extra length for more secure location in domed nut,
Camshaft/rocker cover studs, short, extra length for more secure location in domed nut
Rocker cover nuts, stainless steel
Valves & Fittings
Valve stem caps
Valve adjusters and nuts
Valve springs, standard and sports
Valve spring caps
Valves, inlet and exhaust, Stellite coated
Special large valves, inlet and exhaust, Stellite coated
Tulip valves, PVT
Adjustable Timing Sprocket
Camshaft location bearing, bronze, dress to fit
Ace/Aceca water pump, crank, dynamo belt
Ace/Aceca front pulley- to- fan belt
Two Litre Saloon crank, pulley, water pump belt
PVT linked belting
PVT Distributor DJ6/DK6
Rebuilt distributor or p-ex.
Contact breaker points
PVT base plate
Spark plugs 14mm or 18mm, various types
High performance ignition coil
Dynamo cover plate
The AC ACE had a dynamo that was fitted on brackets and run from the fan belt. The AC 2 litre had a dynamo run off a drive direct from the engine. So, if you have a 2 litre engine you will need to remove the dynamo and cover the hole it leaves with a cover plate. Here is one we fabricated following the dynamo plate exactly. The plan will be to use a gasket sealant behind it.
The lid is off - The rebuild start. October 2017
Here's the first look inside our engine. Overall not too bad. It is 66 years old.
Rocker Cover Nuts sourced from Rod Briggs
These little gems from Rod are very well machined. I gave them a light polish to a mirror finish on the dome and just a light tickle on the sides. Pictures show how they arrived, what they look like polished and how they look on the rocker cover. Each nut comes with a fibre washer.
AC Head Completed
AC 2 litre engine parts arrive - April 2018 - Parts from Rod Briggs
Engine build progress - November 2018
We came to install the camshaft and the reground camshaft that has been supplied was not so good. The lobes looked fine but the journals were not very nice at all. All the journals were pitted and rough. One of them measured about .003” undersize and its out of round. The journals on our existing camshaft are much better but it needs a grind. Photos below.