AC-6 - the website for all owners and enthusiasts of the AC two litre, six cylinder engine




What is an AC Engine?

Engine  Rebuilds

Blocks, Studs & Water Jackets

Spare Parts List One - Attaching Parts, Seals & Gaskets

Spare Parts List Two - Crankshaft & Cross-shaft Assemblies and Chains

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 Used Parts

Parts List


Spare Parts List Seven - Water Pumps......

Keeping the water going round

A legacy of troubles

No engine will run well or, worse, may stop altogether if it is not adequately cooled.  In the AC engine cooling water is circulated by a pump mounted, in the case of the vintage and PVT engines, on the front of the cylinder head, and in the post-war engines, on the side of the block.  While the vintage pumps are driven from the front of the camshaft, the PVT and post-war pumps are each driven by V-belts powered by a crankshaft pulley.

Different pumps... ...same problems 

All original AC pumps have one thing in common......they are nothing but trouble!  Carbon water seals fail, pulleys, bearings and shafts wear and aluminium casings corrode.  Worse, reconditioning of the pumps to their original condition is seldom effective for very long as the design left a lot to be desired.  Additionally, the various types of pump had individual as well as generic issues to consider.  The only solution was to treat each each type and its problems separately.

A typical, very dire post-war water pump

The PVT pump

PVT water pumps are generally in such bad condition when they reach us and have often had such a variety of attempted restorations inflicted upon them that we have found it necessary, and generally more cost-effective, to build completely new pumps from scratch.  To achieve this we have invested heavily in casting patterns for new pump bodies, pulleys and impellers. 

New castings ready for final machining

 Within the pump, all mechanical parts such as shafts and bearings are new and reliable modern water seals are employed to replace the old carbon thrust seal.  This has all been achieved without altering the originality of the appearance of the pump, so important to many owners of PVT cars.



A new PVT water pump

The PVT pump has been one of our best-selling items for the pre-war cars and we are continually making new batches in order to maintain stocks and keep up with the demand.

The post-war pump

The pumps fitted to the post-war cars are all mounted on the left-hand side of the cylinder block but vary slightly in design, the Two Litre Saloon and Buckland pumps having straight water intake pipes while those fitted to the sports models (Ace, Aceca and Greyhound) have curved intake pipes.  Internally the pumps can differ as well.

Sports pump to the left, Saloon type to the right

Our reconditioned pumps have been completely redesigned in order to eliminate the fundamental failings of the original, namely the inadequate bearings at the front of the pump, these now being doubled in number and contained within an extended pulley, the replacement of the bronze bush at the rear of the impeller shaft with one of a modern synthetic material that is tolerant of its working environment, and a modern, one-piece seal vastly superior to the old carbon thrust seal.  

Saloon type pumps, being the more numerous, are available on an exchange basis (as long as the main castings are reusable), whilst customers' sports pumps are reconditioned on request.


A redesigned post-war water pump

Proven Reliability

One of our redesigned pumps is fitted to the Briggs Special and has been tested for many hundreds of trouble-free miles on the road and in merciless use in the component-destroying environment of the speed hillclimb, while many more of our pumps are keeping the water going round in our customers' cars.

Post-war pump fitted to the Briggs Special



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