• Nohab engine components

Nohab engine components

Spares suitable for Nohab Polar

Simplex-Turbulo is a leading supplier of spare parts (both wear and non-wear) suitable for* the following Nohab Polar marine diesel engine specifications. We place a large priority on keeping our stock levels high for all Nohab Polar spares, for all engine types.

Nohab Polar models we support with suitable spare parts and service include:

Nohab Polar - F10 • F20 • F30

History of Nohab Polar marine diesel engines

NOHAB commenced operations in 1847 under the name of Trollhättans Mekaniska Verkstad. The company was founded by Antenor Nydqvist, Johan Magnus Lidström and Carl Olof Holm. Soon, the company was renamed to Nydqvist och Holm AB, which in turn was shortened to NOHAB. The company’s products covered water turbines, agricultural machines, steam engines for road and railway use (starting in 1850) and later complete locomotives with the first steam locomotive leaving the factory in 1865.

Before the First World War NOHAB was the largest private company in Sweden. In 1916, NOHAB became a public company with one of its major shareholders being SKF (Svenska Kullager Fabriken) of Göteborg. The company continued to manufacture a wide range of products including locomotives, 500 of which went to Russia in exchange for 56 tons of gold in payment.

During the 1930s NOHAB began building aircraft motors. The subsidiary NOHAB Flygmotorfabrik AB purchased a licence to build Jupiter engines from the Bristol Aeroplane Co. NOHAB Flygmotorfabrik AB was later renamed to Svenska Flygmotor AB and was eventually purchased by Volvo in 1970. Volvo Aero AB still continues to build jet engine parts for civil and military airplanes (among them the Gripen fighters) as well as parts for the Ariane rockets of the European Space Agency.

Nohab connection with SAAB and Wärtsilä

At the same time NOHAB started a co-operation with AB Svenska järnvägsverkstäderna (Swedish Railway Workshop Limited) based at Linköping and the resulting business was called Svenska Aeroplan AB (SAAB). This company built complete aeroplanes and was also well known for its range of cars.

In 1936 BOFORS purchase NOHAB and the company was renamed BOFORS-NOHAB AB. In the 1930’s, main products were aircraft motors and turbines for power stations. In the 1940’s, BOFORS-NOHAB switched to war production, and after World War II, the company began building diesel engines acquiring in 1948 the AB Atlas range of Polar engines – see below.

In the 1970s the diesel engine manufacturing facility was sold to Wärtsilä and became known as Wärtsilä Nohab.

The Polar part of the NOHAB Polar brand name comes from the company AB Atlas, now called Atlas Copco. In 1898 AB Atlas acquired the rights for Sweden to manufacture Rudolf Diesel’s engine under a subsidiary company called AB Diesels Motorer.  After acquiring manufacturing rights Atlas soon discovered – in common with many other licence holders – that the diesel engine was far from reaching finished development. And it was not until 1901 that Atlas presented the first fully Swedish diesel engine. Shortly afterwards they designed the first reversible diesel engine one of which was fitted to the vessel “Fram” for Roald Amundsen’s expedition to the South Pole. It was from this engine that the brand name Polar originates.

The Atlas Polar engines were initially very successful but they never really recovered from the recession of the 1930’s and in 1948 this side of Atlas’s business was sold to NOHAB, giving birth to the well-known brand name, NOHAB Polar. The last of these engines under the designation WN25 (Wärtsilä Nohab 25) was built in 2007, when Wärtsilä closed the Trollhättan factory.

*If you are operating your engine under the parameter system, please let us know so that we can discuss your requirement.

Vintage Atlas Polar advert from Grace's Guide; the leading source of historical information on industry and manufacturing in the UK.
This camshaft is one of a series of parts that we can supply for Nohab marine diesel engines.
Gasket set for Nohab Polar F10, F20 and F30 marine diesel engines.

Copyright © Grace’s Guide to British Industrial History

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Spares suitable for* Nohab Polar engines

Simplex-Turbulo supports the following models:
F10 • F20 • F30.

Although these engines are now getting old (and in some cases very old), Simplex-Turbulo can still provide service engineers as well as a wide range of parts suitable for* Nohab Polar engines, including the following models:

F10: Nohab Polar SF15 for a five cylinder SF16 • SF18 • SF112 • SF116 (with the last digit/digits denoting the number of cylinders).
F20: Nohab Polar F25 • F26 • F28 • F212 • F216.
F30: Nohab Polar F35 • F36 • F38 • F321 • F316.

These parts are sourced from leading specialist component manufacturers all of which are based in Europe, and are covered by our 12 month guarantee for major items. This guarantee is supported by our £5 million product liability insurance. The parts which we can supply include:

Reconditioning of cylinder heads** • reconditioning of connecting rods and pistons and re-honing of cylinder liners • cylinder head inlet and exhaust valve spindles • inlet and exhaust valve seals • valve springs • valve guides • valve collets • fuel injection nozzles • fuel injection pump elements (plungers and barrels) • cylinder head gasket kits • cylinder liners • piston rings • small end bearings • connecting rod large end bearings • main bearings.

*If you are operating your engine under the parameter system, please let us know so that we can discuss your requirement.
**The reconditioning of cylinder heads includes repairs to cast iron cracks and corrosion pitting, but unfortunately no exchange heads are available. The cylinder heads can be returned as bare heads or built up with new valve guides, valve seats and valve spindles. Class certification is available if required.