Cold Weather Diesel Starting Innovations

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June 15, 2008

Starting a modern diesel engine, in cold weather, is now much the same as starting your automobile. Even more so with the larger diesels like the Cummins ISM and ISX, which do not use any electronic heating aids that require a start wait time. This, however, has not always been the case in both earlier and some other diesel applications.

Caterpillar’s answer to cold start ups on engines mainly used in the construction industry back in the 60’s, employed a “Pup” motor. This single cylinder gasoline engine was mounted near the flywheel and was usually started using a hand operated crank. Once running, a manual clutch was slowly engaged that drove a pinion that turned the main engine. Soon after the big diesel started to be rotated over and over, a plume of white smoke would belch out of the exhaust followed by an accelerated roar. The pup engine clutch was then disengaged and the little motor turned off. The big Cat was running.

International’s answer for cold starts on similar equipment back then was a little different. The big diesel actually had a set of spark plugs like a gasoline powered engine. It also had two fuel tanks, a large diesel and a small gas. A very small hand operated crank or knob was turned all the way in one direction. This somewhat relieved the compression and introduced straight gas to the electrically cranked engine. Once started and slightly warmed up, the crank or knob was rotated in the other direction. This returned the engine compression back to full as diesel fuel was introduced through the injectors. The gas flow was then totally disabled and the diesel engine was running and ready to work

The Future Duramax Diesel Engine

Additionally, cold weather starting aids like hand bombed ether and ether injectors were used. Today, use of ether is not recommended as a start aid and can even be very dangerous if used on heated intake grid equipped engines. Ether was also know to bend or break connecting rods as well as cause other internal damage.

So, in comparison, our diesels today, whether they are equipped with glow plugs, heated intake grids or pre-combustion chamber designs, are a far sight simpler and safer to operate. They are all direct electric start. 12 volts for all engines up to a given size, then 24 volt is used as the amperage required for the 12 volt becomes impractical as far as cabling size and heat build up.

Next time you start up your diesel, think of all the work and development that has gone into making what we probably take for granted; a quick, no fuss, start.

There are many components that contribute to smooth cold starts from the ECM (Electronic Control Module) to even the fuel composure of today. So, even though we think it can’t get any better than this, it will. Design improvements in diesel development will inevitably gallop on.

Note: The winter photo was taken at the Spartan’s Charlotte, Michigan service camp area, on January 1, 2008.

With A Starting Thought – Lug_Nut   –   Peter Mercer 

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  1. Pingback: Anonymous

  2. i worked at gyuro grading and exavating in 1977 and we had 4cylnder engines pony motors that started our main diesels on the D9 push cats and the Elturno pulls all made by caterpiller.

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  4. Don Eyre

    The Cat engines referred to as being from the 60’s were actually a lot earlier than that. My dad had a D2 Caterpillar tractor that he bought new in 1939. It had a 2 cylinder starting motor that you wrapped a rope on the flywheel and pulled. I saw him start that tractor in extremely cold weather. Some of the early John Deere diesels also had a starting motor these were about 1949 to1960. Don’t recall any engines with a 1 cylinder starting motor

  5. John, Thanks for the input. All of us writting these blog articles really appreciate positive comments, or for that matter, any comments or point of view. Again, thanks for your comments.

  6. John


    This ceratinly brings back many memories with ether can in hand
    up in the Yukon and N.W.T., brrrrrrrr.

    Great to see the technological changes advancing.


  7. Great article to read.Cold starts on same equipment.