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FAST FRED (209.26.110.234)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, January 10, 2001 - 12:32 am: | |
Some info that was posted long ago that might help the new folks understand how to get a DD started when its COLD.
My old Diesel book says : "Starting a diesel engine is not as easy as starting a gasoline spark ignition engine.
Normally, faster cranking speeds are required for the diesel engine.
At low cranking speeds , there is too much time for the required 'heat of compression' to dissipate.
While cranking speeds vary with different types ,a cranking speed of 200RPM is required to obtain a compression pressure of 400 psi.
AS cranking speed is increased less heat is lost to the cylinder walls and compression temperatures rise."
"The problem of starting a diesel in cold weather is extremely difficult and usually impossable if adequate accessories have not been provided to assist in the starting process.
However with auxilary equipment starting time of a medium size diesel ranges from 3.7 to 7.5 seconds at temperatures ranging from 25 deg F to - 25 deg F.
The type of accessory equipment may vary with the temperature."
The methods used to aid starting under cold weather conditions include:
1 special fuels
2 heating the coolant
3 heating the lubricating oil
4 air heating the engine
5 heating the intake air
6 auxilary heat from glow plugs
7 heating the starting battery
With ether systems it is possable to start a diesel at sub- arctic temperatures in 3 to 12 seconds.
Ether is NOT a petroleum product and not affected by temperature.
BY using it for starting purposes ignition temperatures are materially reduced.
Cranking requirements to reach a temperature conductive to starting are also lowered.
When cold fuel enters a cold combustion chamber and the air from the intake manifold is also cold , the fuel fails to evaporate.
Instead it collects in the combustion chamber ,washes the lubricant from the cylinder walls , and dilutes the oil in the crankcase.
Some coolant heaters used are :
1 external tank circulating type
2 freez plug type heater
3 head bolt type heater
4 drain plug type heater
5 water jacket type heaterd
6 boiler system heaters
Without extra heat , the only way would be to have less voltage drop.
Using more real start batts ,with{ none of those" RV Marine Deep cycle starting " } that are poor at everything.
If your in a temp that requires lots of amps to spin the batt and cant at least power a batt heater , if two batts wont do the trick ,, install 2 or 4 more.
IF the house batts are real deep cycle stuff,somtimes the extra amps avilable will hold the volts up.
The article seemed to want to use the ether when very very cold as the fuel of choice.
I found at +17F that the first {and only} shot of ether should at least half fill the cup{two "capsules worth" }in Greyhound lingo, and she sprung to life .
I did use a small magnetic lube oil heater to keep the oil a bit easier to get to the bearings,, dont know if it spun any faster .
I use 1 8 D real starting and two 31" RV Marine Deep cycle starting "junk that came out of my old motorhome,, but its enough. 12V requires lots of amps!!
Addundum:
I now use a block heater installed directly into the block.
It came from US Coach and was a real fun item to install.
After I removed the 4 bolts where the heating element was to be installed , on trying I couldnt even get my pinky into the block , yet when the long element was slowly wiggled in , it went in no sweat.1500W at 120V , three hours seems plenty.
The coach now starts in the teens like it was shut off a few seconds before.
There is very little of the usual below freezing white smoke on start up.
Ether IS the fuel of choice for starting in very COLD weather.
Because of its special cold weather behavior.
BUT it is NOT fuel to start a coach when its warm out.
IF you run out of fuel ,or are trying to get some old coach , abondoned without proper fuel system procedures started , WD 40 is much less likley to break piston rings .
Ether is ONLY for below 40 deg on DD engines, other mfg. may be different.
"Gentlemen Start your Engines!
FAST FRED |
Mike Eades (Mike4905) (207.190.11.42)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, February 04, 2001 - 9:21 am: | |
I do know that in a jam I have bought a bag of charcoal and light it in a metal pan of some kind and then put the coals under the oil pan and let the heat rise. I have started a Cummins and a DD in Buffalo NY in the winter when my hot box failed to do the job. Mike |
Buswarrior (Buswarrior) (152.163.213.181)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, February 04, 2001 - 7:42 pm: | |
Another old story about frozen buses:
My father used to do ski charters to Vermont in the 70's. Got so cold & windy one night, none of the buses would start. Dad's motor wouldn't even try to turn. The local "authorities" arrived with a couple of those propane powered construction heaters, aimed them under the back end, and tried to block the high winds with cardboard to keep the heat aimed up under the motor. Got the rest going. Dad's bus had to be towed in to the local garage. 20 minutes sitting inside the garage, and it started as if nothing wrong! No surprise to local authorities: "She was just froze up" Which, of course will offend all the technical types.
Something spiritual about buses that defy engineering. Nuff said!
happy coaching!
buswarrior-MC8-ON |
Dave (64.111.120.170)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, March 05, 2001 - 3:57 am: | |
In Colorado in the mid 50s, my dad was at reservoir 22 at 9500 feet. The mechanics never shut the diesels off all winter, they changed oil and fuel was added at idle. pull the drain plug oour in fresh oil when the color changed install oil plug. If the engines died, they put fires under the ingine to restart them. That is why we are in sunny California/ |
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