Cummins engines Down Under
At the 2019 Brisbane Truck Show Cummins celebrated its 100th anniversary with a display of engine models that made significant contributions to the Australian road transport industry.
What is believed to be the oldest Cummins-built engine in Australia was recently recovered. After many years powering a milking machine on a dairy farm near Toowoomba in Queensland, the engine lay idle in a dismantled state, due to a failed rod bearing.
A three-horsepower engine, it was probably built in the first half of 1922, under a license granted to Clessie Cummins by Robert M Hvid, who owned the US patents for the fuel and combustion system.
1929 Model F being restored in Perth
This was Clessie’s first diesel engine project as joint founder of Cummins Engine Company, with banker William G Irwin.
The fledgling Cummins Engine Company started building the Hvid engines in 1919 in Columbus, Indiana, for giant American retailer Sears, Roebuck & Co, which sold them to farmers through its mail-order catalogue.
Unfortunately, the Hvid engines were unreliable and Sears cancelled the contract soon after the Brisbane Truck Show display engine was built.
Clessie Cummins went back to the drawing board and, after a series of experimental engine failures, produce the first truly-Cummins engine, the Model F, in 1924.
A 1929 Model F – originally purchased by the Puglisi family to power a NSW coastal fishing boat in the 1930s – has been restored and is proudly on display in Cummins’ Perth branch.
In the early 1950s, Cummins did some research on the post-WW II Australian truck market that was then dominated by underpowered European diesel lorries and mainly petrol-powered North American trucks.
Blackwood Hodge was the service agent for Cummins Diesels and also did some repowering of petrol and other-brand diesel trucks, using the Cummins JBS, 150bhp engine.
The larger Cummins HB600 – forerunner of the famous 14-litre, N-series – had less appeal, because it was heavy and expensive and there were no drivelines capable of handling its torque.
Linehaul was virtually unknown at that time, so the decision was made in 1961 to introduce the new C-series, a 464-cubic inch (7.6-litre) in-line six that had the Cummins PT fuel system and was offered at 160bhp (naturally aspirated), 175bhp (turbocharged) 180bhp (supercharged) and 190bhp (turbocharged).
The newly formed Cummins Diesel Australia assembled four C-series engines per week in Melbourne, taking advantage of favorable tariff regulations that favoured some Australian content.
It soon became apparent that these diesel engines could halve petrol-engine fuel bills and significantly improve life-to-overhaul, providing at least 150,000 miles versus 70,000 to 80,000 miles for petrol engines.
The supercharged C-180 engine on the BTS display developed 180bhp at 2500rpm with peak torque of 410lb ft at 1700rpm.
In the USA the C-series was offered in Diamond Reo, White, International Harvester, Kenworth and Peterbilt models, but the main users in Australia in the 1960s were International Harvester and Dodge.
Although the original C-series remained in the IH line-up until the Mid-1970s, changed truck weight and length regulations and the success of two-stroke Detroit Diesel linehaul engines saw Cummins introduce the 14-litre N-series.
Cummins’ big-bore V-series engine, the 903, was released in Australia in the early 1970s. It was the top-capacity engine in a range of V6 and V8 diesels that Cummins developed to suit short cab and COE prime movers in the USA.
The smaller-capacity V8 555-cubic-inch ‘Triple Nickel’ was a popular IH ACCO engine and the 14.8-litre V903 took International’s ACCO 3070 and Ford’s Louisville LNT9000 to linehaul success.
Simple changes to the Cummins PT fuel pump provided ratings of 280, 300 or 320bhp and the 903 became the Australian trucking industry’s first true half-million-mile-to-overhaul engine.
A turbocharged VT300 version followed and remained the powerplant for the Louisville until 1987.
As a truck engine the 903 became the victim of emissions laws and the demand for improved fuel economy, but the VT903 is still in use in military applications, including the 675hp US Bradley Fighting Vehicle.
The legendary 855 cubic inch (14-litre) Cummins engine had its origin in the late 1950s as the NH model, initially rated in Australia at 250bhp.
As improvements were made to Australia’s highway network and the loads got heavier, the turbocharged Cummins N-series came into its own as a true ‘big banger’.
By the mid-60s, it was available with peak outputs of 335bhp and 900lb ft. This period also marked the introduction of Clessie Cummins’ invention, the Jake Brake, although manufactured by Jacobs.
Through the 1970s and 80s, the 855 cubic inch engine went through various development phases, characterised by being called ‘Big Cam 1, 2 and 3’ engines. In the USA there was also a Big Cam 4 engine, but the local Cummins marketing people thought the ‘Big Cam’ nomenclature had gone far enough!
The 86NT was released in early 1986 and featured the greatest changes to the 14-litre engine since its inception. It no longer had three interchangeable heads and also featured early electronic injection control of the PT fuel system.
The NTC-444 broke set a new performance standard with 444bhp at 2100rpm and peak torque of 1400lb ft at 1300rpm.
Through its nearly 50-year history the N-series’ power more than doubled, from 250bhp to 525bhp and torque peak almost trebled.
Cummins N14 ‘Red Head’ Celect
In the mid-1960s, Peterbilt, Kenworth and International imported American trucks introduced the first ‘big bore’ Cummins engine to Australian operators.
The NH model was the start of Cummins legendary 855 cubic inch (14-litre) engine family. Through the 1970s and 80s, the 855-cubic inch engine went through various development phases, such as the Formula low-rpm concept and the Big Cam series of engines.
The time-honoured 855 emerged in extensively revised form in the early 1990s. Known as the N14 ‘Red Head’ Celect, it featured full-authority ‘Celect’ electronic controls and eventually peaked at 525bhp and 1850lb ft of torque.
October 2002 saw the last Cummins N14 on-highway engines roll off the production line.
Cummins Signature 600
In 1996 a new 15-litre engine Cummins was in development, codenamed ‘Apex’. When it broke cover, initially as the Signature 600 and later followed by the ISX family, it was the most advanced heavy-duty diesel engine developed by Cummins.
The Signature 600 punched out 620bhp and peak torque of 2050lb ft. The 15-litre Signature/ISX family established new benchmarks for performance and fuel economy while complying with stringent emissions standards.
The 15-litre Cummins was the first heavy truck diesel engine with electronics and dual overhead cams as integral parts of its innovative design. The dual overhead cam design allowed Cummins engineers to optimise engine and braking power.
The Gen II version was released in 2003 to improve reliability and durability.
Like all linehaul engines in Australia the Signature/ISX engines have had their share of troubles – particularly the EGR-equipped versions – but, through it all, road transport operators have praised Cummins’ service backup, Australia-wide.
The Signature/ISX family continues to be developed, as the 2020 Euro VI derivatives and 2022 ‘Android Engines’ showed.