Hi, Folks.
Please feel free to correct me if I am wrong but I was taught on cold starts to start the pony motor, let it warm until it is running fairly smoothly - but not too long 'coz it doesn't have coolant circulation until the diesel is turning - then engage the diesel with the decompressor open until the oil pressure comes up, close the decompressor and let it turn over until you think it is warm enough to start, then and only then, open the throttle. If it doesn't fire up pretty quick, close the throttle and let it warm some more, then try again. Wash, rinse and repeat until started.

Then turn off the gas to the pony and let it run out.

Just my 0.02.

the way i was shown by the cousin was to run the pilot engine a couple of minutes to let it warm itself, then start winding the main on decomp when the mains intake is getting a bit of warmth to the touch and you have fuel and oil pressure open the fuel and drop the decompressor at the same time it should fire almost straight away. well our machine always has.

people forget the pilot engine is the glow plug for these old girls. another important point is have a rain hat or tin can on the pilot exhaust to stop the moisture eating it away and dusting the main engine it would also cause problems starting with exhaust fumes getting in the engine.

Some people just dont understand that diesels dont start and run with spark plugs, [except the old IH's} compression builds heat, turning the engine over on compression builds up heat in cylinder area, pistons liners, prechambers and valves, get the metal warm and the engine will fire. Adding cold fuel just cools things down and washes the oil away from the rings.

Rome wrote:

Good example!

What a moron, thats a really decent dozer and it will b e flogged out well  before its time
 

Rome wrote:

 wrong timing can do to an engine.

 

I thought the outcome was that the timing was off and caused the injection sequence to start early thus causing fuel to be injected onto the outer perimeter of the piston instead of the combustion chamber and ignited there. Doesn't matter how you start your machine if the timing is out it's not going to end well.Also older cats have pre-combustion chambers so they are unlikely to suffer from the same issues as the A/C engine. The only issue with their diagnosis is why did the timing issue not affect the other cylinders.
When I worked for a company that built garbage compactors they had thirty Freightliners with Cat engines in them. The computer in them revved the engine to about 75% as soon as it started. That would have been twenty to twenty five years ago.

John Deere farm tractors from the 70s, 80s, and 90s would like to have a word about revving to full throttle upon startup.

d9gdon wrote:

John Deere farm tractors from the 70s, 80s, and 90s would like to have a word about revving to full throttle upon startup.

Amen!  I cringe every time the 4440 fires up. Deere has a system that moves the rack to full throttle for startup before returning to the throttle setting. I'm old school that believe in low revs until oil is circulating and the engine has warmed some. .
 

Hi, Folks.
If my memory serves me rightly, both Ingersolll Rand and Gardner Denver air compressors used to power the air track drills of the 1950s, '60s and '70s went straight to FULL throttle on start-up. I often shook my head thinking about what that might be doing to the engines.

Also, many emergency stand-by gen sets were set up to go to full throttle immediately upon start-up to minimize any interruptions to power in places like hospitals, etc..

Just my 0.02.

i watched a video the other day on 671 gm it had been sitting for several years.

it had been the drive for a fire booster pump for a steel works and was set like that give almost full throttle to start and then the governor would regulate it.

Should  warm pony , crank main with decomp in start until you see oil pressure then decomp in run  cranking with compression, not fuel until the manifold is warm then try fuel if it’s white unburnt fuel off and more cranking try again when the main takes off set it a little over idle speed , turn of the pony fuel  and set it to idle burning the fuel left it the pony carb ..  that’s what I do. Anyway!!