HURTH – HSW – HBW – IRM – BW Marine Gearboxes

All of these ‘replaced’ designations for marine transmissions now fall under the banner of  ‘ZF’.

There is still some confusion in the field relating to the early designations and we receive many contacts from owners and operators seeking information and spare parts.

We are here to help, so please do not hesitate to get in touch, if we can help, we will help.

The quality built into the early boxes is reflected in the age and condition of many of the units which we come across, rarely are they just’ worn out’.

It seems to take a serious regime of neglect, or a catastrophic accident, to put the old units beyond  economical repair. Some of the units we come into contact with are 25 – 30 years old, and still ‘going strong’!!

Today,  ZF continues to uphold the  tradition for quality of construction and coupled with advanced materials and manufacturing methods, operators can continue to have real confidence in the ZF product.

To clarify :

The original HURTH marque covered the  HBW & HSW gearboxes from HBW 40 to HSW 800 and these now translate into the ZF M and ZF models.

For example – HBW 12 mechanical gearbox becomes  ZF 12M. HSW 25 Hydraulic clutch becomes ZF25.

There have been changes over the transition period so always best to check..

Lubricant used in all of these models is ‘in the majority of cases’ ATF.

Always best to check. Incorrect lubrication can wreck your gearbox!!!

The original IRM marque covered gearbox models from IRM 220 to IRM 350. This series now translates into ZF models .

For example – IRM 220 becomes ZF 220. IRM 325 becomes ZF 320.

The additional letters and numbers attached to the stem no e.g., ZF220 V or ZF220A indicate the configuration of the input and output shafts.

ZF220V = Output shaft under input shaft. Vee configuration.

ZF220A = Down angle output shaft.

Lubricant used in these models ‘in the majority of cases’, SAE 30 or SAE 40 dependent on the area of the world where the gearbox is to go into service.

These oils are ‘straight’, not ‘multigrade’.

Always best to check. Incorrect lubrication can wreck your gearbox!!!

The BW marque relates, in general, to the larger gearboxes – Commercial , Large pleasure craft. The BW designation has now become ZF. e.g.

BW 165 becomes ZF 650.

BW 195 becomes ZF1950.

When dealing with this range of gearboxes – always best to consult.

River Teign & Teign Estuary Boat Tours & Private Hire Service.

From early 2014 our new SEAPRO shallow draught 8-10 passenger inflatable ‘Kestrel’ will begin operating Boat Tours on the River Teign and surrounding waterways, from Newton Abbot’s Town Quay, opening up access to some of the most inaccessible, fascinating and beautiful stretches of water and wetland in the South West.


Please let us know your availability dates and we will do our best to accommodate you.

Please enter your contact details and as much detail as you can about your problem. We will get to you as soon as we possibly can.


One of the bird names used by vessels working around Newton Abbot’s Town Quay in the late 19th and early 20th century. We have continued with the tradition in this new venture. We will continue the theme as other types of craft enter service.

‘Kestrel’ and her experienced crew can be hired by Groups, by the hour, for River and Estuary Tours, Bird and Wildlife Watching, Photography, Art, Historical tours, Wedding parties wishing to arrive by water, or just for a Cruise to Teignmouth and back (or not, if you wish to stay there) Also, there will be scheduled trips up the river and down to Teignmouth with individual places available.

We will offer a service to carry bicycles between Newton Abbot and Teignmouth, filling the gap until the new cycleway is completed.


The upper reaches of the River Teign are very beautiful and abound with wildlife, The waters are mostly inaccessible, even by boat. This was a major consideration when choosing the type of vessel to put into service, With ‘Kestrel’ we believe we have it right.

Don’t forget your camera!!!

The tidal waters and wetland adjacent to Town Quay and the newCycle/Pedestrian Bridge are diverse and complex. Very large Carp, Pike, Brown Trout, Sea Trout and Salmon share the River Teign at Newton abbot with breeding Sea Bass, Grey Mullet, Crabs and Eels. The largest Flounder ever caught came from the Teign. We found a pearl in an oyster last year – it’s in the local museum now.

Occasionally, a seal will find it’s way up the river, Otters have been sighted (though their location is secret), Mink roam freely. And was that a crocodile you saw under the branch where the Python is sleeping???

The cross section of birdlife is amazing. Ravens, Buzzards and Peregrine Falconspatrol the skies over the reed beds. Warblers and other small wetland birds are constantly on the alert. Herons, Egrets, Cormorants , Grebes and many other water birds are common and from time to time a large number of ‘Twitchers’ will descend on the River as some ‘exotic’ species is sighted. The Kingfisher in flight remains one of the most exciting sights. The River Teign is home to quite a number of these beautiful birds.

Insect life abounds and it is doubtful if anyone has the full list of plants which inhabit the marshlands and banks of the waterways.


Newton Abbot and it’s Town Quay have a maritime history. Humphrey Gilbert, a local seafarer stepped ashore at St Johns, Newfoundland in 1583 and claimed it as an English colony. Compton Castle, home of the Gilbert family still exists and is open to the public as a National Trust property.

For over two centuries there was a steady trade between the Port of Newton Abbotand the Cod Fisheries of Newfoundland. Sailors gathered in The Newfoundland Inn or the Dartmouth Inn in the hope of joining ships bound for the cod fishing grounds. A steady trade flourished in the town, making equipment to supply to the ships.

The Stover Canal was built in the 18th century connecting the ball clay workings and granite quarries with the River Teign. The Stover Canal Society was formed to preserve and restore the canal. The work goes on.

The Vikings used the river to reach Kingsteignton. They failed in their endeavours, it’s still there!

Stand By To Be Amazed!



Lack of proper maintenance and neglect are major causes of Marine Transmission failure

ZF Marine Transmissions are manufactured to the highest standards, and if correctly maintained offer years of trouble free operation.

Lack of proper marine transmission maintenance and neglect are major causes of transmission failure.



Highly corrosive and works away at wrecking surfaces which it may have only briefly touched.
We see too many gearboxes which have damage to the output shaft bearing , seal surfaces and propeller shaft coupling which is directly attributable to salt water contact.
Keep water out of your bilge and away from your gearbox at all times.

Winter is here and the risk of frost damage to your gearbox is very real.
Some gearboxes have oil coolers bolted to them, some gearboxes have integral cooling passages and some gearboxes do not rely on heat exchangers to keep them cool.
If there is a gearbox water cooled heat exchange system of any kind fitted or integral to your gearbox there is a risk of frost damage during adverse conditions. Take precautions, inhibit the system.

Some dissimilar materials immersed in salt water particularly, can produce electrical currents and over time these will erode cooling system components.
If you have anodes, check them regularly and don’t skimp on changing them. A replacement tube stack is expensive. Check for visual signs of erosion and from time to time remove covers to inspect. Borescope where accessibility is a problem.
Act quickly if there are signs of electrolytic action, there will be a cause.

The specification for the recommended oil for your particular gearbox is there for a reason, be sure that the correct type is fitted, and change/clean the filter according to the manufacturers recommendations. Check regularly for lubrication leaks and if there, find the cause.
Catastrophic failure of your gearbox is vastly more expensive than a well maintained lubricating system.

Who cares what it looks like so long as it works?? Think again!! A scruffy/ rusty gearbox tells you immediately that it is neglected.
How on Earth are you going to check all of the points we have raised if your gearbox is a ball of rust. Clean it up and keep it that way – Your life may depend on it!!

Check control cables and anchor points for wear and tear. Check hydraulic and cooling pipes for deterioration and leaks. Check clips and seals.
Anything unusual, get it checked out.


If it can happen, it will happen


ZF 4650V marine transmission commissioning onboard a M32 Princess Yacht

Pilkington Marine visited Princess Yachts in Plymouth to commission the ZF marine transmission setup. This was only her second trip out to sea.


The ZF4650V marine transmission is a V Configuration Gearbox, allowing for the engines to face astern. The space saved can be utilised by the boat designers in many different ways. In this case the area is used as the crews quarters, giving them more comfortable living arrangements, as opposed to being jammed down the side of the engine/transmission setup!

jez-pilkington-commissioning-zf-marine-transmission-168x300The oil pressure was checked both before and after the oil filters, under power, and at idle. Gearbox lube oil was changed to suit the destination of the vessel. 40 weight gear oil is used in hotter climates, 30 weight for the northern climes. The sludge drains were checked for debris, and found to be immaculate (as expected!)

Test unions with snap connectors were used to connect into the lubricating labyrinths, to gather exact data on pressure at all times.

The onboard alarms were fully tested by the disconnection  of the sensors on both the port and starboard engines.

(see the composite photos of both the alarm in on and off state on the computerised warning panels below )


The engine room onboard the M32 is an interesting place. You will see a pair of MTU 16V engines (2600hp each at 2500RPM) They have three turbos, and huge stainless steel exhaust manifolds. working inside this room without ear defenders is impossible, and with the warning alarms sounding it is even loud with these on!



Walk past the power units and through another door you will find the Tiller Flat. Inside is the master fire extinguisher, and the climate control systems that keep the engine room temperatures down. Every system onboard this state of the art vessel can be monitored from the bridge, and remote cameras can see all around, from the stern to the bow, nothing is missed by the skipper. This really is a vessel for the 21st Century. Amazing.


Messing about in Power Boats with Mike Pilkington

This article was first published in The Deesider – July 1970

What has Frodsham in common with Cowes, Lords or even Twickenham? They are all headquarters of sport, and believe it or not, this Cheshire village has become the home of Britain’s newest sport.

In March, on a disused stretch of the Weaver, shunned by fishermen because of its high pollution content, power dinghy enthusiasts gathered to stage the first ever race in this country.What began as a publicity stunt for a marine engineering firm from Frodsham introduced this exhilarating type of power boat racing to Britain. It is already a highly popular sport on the continent especially in France and Italy.


Mike Pilkington, the 34 years old head of the firm (another William Webb Ellis?), said, ‘I didn’t realise what we had started. There was so much enthusiasm about it.’

The Weaver Sailing Club, of which he is a member, soon organised a power dinghy section—one of the only sailing clubs in the country to have one.
As the sport spreads throughout the country, Michael believes it could end the
rift between sailors and power boat men.

The second event took place at Frodsham on Whit Monday and attracted entries from all over the country, including London and Poole, in Dorset. The races involved two one hour runs and the winner is the man, or woman, who completes the most laps. One winner travelled 73 miles in his event. The joy of the sport is that it brings power boat racing into the reaches of ordinary people. Anyone who has an inflatable dinghy can race.

A big off shore power boat such as John Kennerley’s Maltese Magnum Twin, the Wirral boat which went aground in last year’s Round Britain Race, can cost thousands of pounds. Next in line come the power boats which are raced or circuited, inshore, mainly on Chase Water in the Midlands.

These are expensive craft costing between two and five thousand pounds. But the new inflatable outfits range from £250 to about £800 with engines in all classes between 175 cc and 850 cc. Taking the smallest craft, the engine can cost £170 and the boat £80. They are capable of 17-20 mph and are Well in trophy winning range.

For those not of a competitive nature the craft can be used for pottering about on holiday, fishing, or even pulling water skiers. With an average length of 12 feet they can be dismantled, packed and put on a mini’s roof rack and taken on a day’s outing.

Racing the boats looks exhilarating and to the layman even dangerous, but an inflatable craft has inherent safety. The only dangers are hitting something solid or falling in front of an approaching dinghy and being hit by the engine. Colliding with another craft produces a dodgem car effect. Anyone who competes in a race has to wear a crash helmet and a life jacket and use an ingenious safety device. The driver is attached to the engine by a jack plug and if he is thrown overboard it cuts out the engine.

On Whit Monday, a grandfather who travelled from Poole had his boat overturn on top of him to no ill effect. Speeds are limited in dinghies. There is much more skin friction than with a fibre glass or wooden hulled craft which keeps it down. Manoeuvrability is an essential with them and too high speeds would prevent this. Next year there is a possibility of international events at Frodsham and even an attempt at the dinghy world speed record of 52 mph.

Remarkable that a mere publicity stunt has finally put Frodsham on the sporting

Perhaps we need Mike to start something similar on the Teign Estuary? He has the pedigree for attracting people on to the water…


The Shearwater : A Refit at Pilkington Marine with a ZF gearbox & Cummins Marine Engine

The Shearwater is a long term refit project for Pilkington Marine.

It took a year for Southampton University to work out whether the hull of the shearwater would be up to the task of putting down the power of the new powertrain.

The old engine was the VW TDI 225-6 Diesel Engine that gave a top speed of 13 knots. With the new power train installed Cummins QSB 6.7litre 480hp @ 3300RPM driving a ZF gearbox (85A) with a Gold Line Michigan Prop 26×30″ pitchwe are expecting a top speed of nearly 30 knots.


Above you can see the carbon fibre mat wrapped keel before it is finished off. (more pictures to follow) 

The custom install of the new drive train setup includes a carbon fibre mat wrapped around the keel and prop tunnel. Carbon Fibre (Bi axel) is now coated with 7 coats of gel protect, then an underwater primer before finally the anti-foul is applied. If looked after this finish should last a lifetime.


Above you can see the a close up of the keel edge – 7 coats of Gel Coat still to go!

The new engine will be fitted next week, as will the ZF Gearbox, and on the run up to Christmas the boat will be in the water for testing. As she progresses we will post more updates to this blog showing our progress.

Progress Report

Karen has now keyed the Carbon Fibre keel ready for the first of the Gel Coats. The Gel will only bond properly with the surface if this is done correctly.


You can see the other end of the prop shaft in the above photo. Below you can see the custom chrome end of the prop ready to fit to the drive train within the engine bay (if a job is worth doing, it is worth doing properly)



Next, a view of the whole of the engine bay, gel coated and prepped ready for thecummins marine drive train.


We have the Cummins QSB 6.7litre 480hp @ 3300rpm sat ready to be installed into the engine room. This is a brand new power unit, we haven’t even fired her up yet, as it has been dyno tested by Cummins at the factory.



Newton Abbot, a view from the water

Newton Abbot does not immediately stir the imagination when it comes to waterways, and some of the spectacular sights which are available within a short boating distance of Town Quay.


Just look at the pictures collected from a small boat on the River Lemon and you will be transported to the backwaters of Strasbourg or Venice. Looking at Newton Abbot from a different angle totally changes your perspective on the place. Gently meandering up The Lemon at not a lot more than walking pace gives you time to soak up the atmosphere between the houses and industrial spaces. People wave from kitchen windows, looking genuinely surprised at you chug past. Children wave from the bridges with a look of astonishment on their faces.

Moving on to the River Teign brings the magical world of the Amazon rain forest to mind. You expect a gorilla to come bounding down to the waters edge, or a parrot to come squawking past. We watched a Heron move from branch to branch in front of us, enhancing the feeling of being in a different world. we motored on until we ran out of water,  less than half a mile from Teigngrace. We intend to time the tides a little better very soon and cruise even further up the river. We knew we had gone as far as we could, when a gentle bump let us know we had finally run made contact with the gravel of the river bed.



Hackney Marsh is a wonderland for wildlife watching and is highly accessible at certain states of the tide via the multitude of creeks and backwaters. If you have ever been in the Everglades in Florida you will be at home in the watery wonderland that very few people see, even though a large proportion of the visitors to South Devon whizz overhead on the dual carriageway.



Future plans for the development of Town Quay should make these sights and sounds more accessible to the local community and visitors, imagine the possibilities of guided tours, or of rented canoes splashing about among the reeds.

Watch this space…



Not Just World Class Racing Clippers, But Fishing Boats Too!!

Following her exploits at sea with the round the world racing clippers Karen came to earth with a ‘splash’ and joined a fishing vessel to travel almost 50 miles out before tangling with the big cod fish.


When you are that far out, reliable engines and transmissions are essential. Not much fun in a drifting boat with a few cod for company.

Fortunately, this vessel is in first class order and the machinery never faltered, adding to a great day’s fishing under a clear blue sky. Good old ZF, a real fishermans friend!!

*The staff and friends are still eating the catch, if you ever turn up at the Pilkington Marine HQ you may well be offered some Thai Fish Curry from the proceeds.

Clipper : Round the World Yacht Race

Karen and Jez Pilkington are privilaged to have been invited to be amongst the first people in the world to sail aboard the new Clipper 70 Racing Yachts.

The special invitation came via the Pilkington Marine Ltd connection with Cummins Onan Generators which were chosen to be fitted to the yachts because of their proven reliability under challenging conditions.

Karen at the helm of ‘Switzerland’

Karen at the helm of ‘Switzerland’

Designed by the highly respected naval Architect Tony Castro, the new Clipper 70 will form the third generation of ‘Clipper’ racing yachts designed to take the Cipper Round the World Yacht Race next year.

Clipper Ventures is the international marine events company founded by Sir Robin Knox- Johnson in 1995.

Watch this site for an update on the experience.

Karen taking instruction from Vicky Ellis the skipper of ‘Switzerland’.

Karen taking instruction from Vicky Ellis the skipper of ‘Switzerland’.

Newton Abbot Civic Society Reward Effort

Today, Karen and Jez Pilkington were presented with the first ever award by the Newton Abbot Civic Society for voluntary efforts to improve the town.

Following the construction of the new pedestrian/cycle bridge spanning the River Teign at The Town Quay, Karen and Jez decided to take a hand and removed van loadsof unsightly junk from the river. Wheel chairs, shopping trolleys, road signs and old bikes were amongst the items recovered.

This was not the end, the couple then separated the scrap metal, sold it to the local scrap yard and handed the proceeds to Rowcroft Hospice.

Karen commented “The river frontage is part of ‘The Ancient Port of Newton Abbot and we are proud to help take care of it”.

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