TheMoose

I'm new to diesels & have been trying to learn about them enough to know what I'm talking about.

I just noticed that the Cummins M11 (370 HP 1320 ft lbs of torque) in the fire truck I drive doesn't have glow plugs or at least it doesn't have the light that you wait to go out before starting it.
is that the way all the big diesel engines are, I haven't seen a glow plug light on any of the fire trucks but the diesels in pickups all have them, why is that??
just wondering!! ???

Dr. Evil

Maybe because firefighters tend to be impatient when leaving the firehouse.....usually isnt time for the wait to start light to go out....as well, arent the firetrucks plugged in all the time??

We have a couple of Cummins driven firepumps at work. When they turn on, they go to full load in a matter of a few seconds....regardless of temperature. Its not easy on the engine, but its not practical to wait for the engine to warm up while the plant is burning to the ground.

TheMoose

All the newer fire trucks have plug ins & are susposed to be plugged in at all times, none of the older trucks have plug ins & they don't have the glow plug lights either.

I've been driving these trucks for over 20 years & never noticed this before I got my CTD Ram!!

Our grass rigs are 2000 1 ton power strokes & are plugged in all the time & they do have a wait to start light & yes I'm impatient waiting for it to go out!! LOL!!.

Raspy

Direct injection diesels where the fuel is injected directly into the cylinder instead of into a pre-combustion chamber don't need glow plugs and the "wait" on my '93 turns on an intake air heater, not a glow plug. Also they are temperature dependent. The only time mine would not light right off was at 6000' elevation and 9 degrees temperature. I never wait for the light unless it's really cold. One of the great things about the Cummins is how they start.
On old marine engines with pre-combustion chambers and relatively low compression you can aim a burning propane torch into the intake or build a little fire with a diesel soaked piece of paper in the intake and start them.

Mexstan

In my youger years we used to operate a whole slew of farm tractors with diesel engines. None of them had glow plugs as they were direct injection. On cold morning when it was close to zero they were hard to start. It was a common practice to remove the air cleaner, twist some newspaper into a long 'stick', light it and hold it over the intake while cranking the engine over. The injectors also had a button incorporated into the shutoff lever that we pushed to supply extra fuel. At least that is what I think it did. When the engines started they spewed out a lot of white smoke until they warmed up.
We also had one old tractor that was not direct injection and I have a vague memory that it had glow plugs. It also ran extremely quite and did not sound like a diesel. Think it was a Maguirus Benz.

Raspy

I worked on a ranch in Nevada for a while with very cold winters. One of the worst things I saw done to poor diesel engines in the cold was to spray a big amount of starting fluid into them, start them (which resulted a bunch of terrible knocking) and then some guys would spray more in. This would make the engine go to full on preignition with a terrible racket and the engines would actually slow down. EeeeK! It actually broke the crank in one.
We had one old Cat that would not start on its own so I would pull start it with a big four wheel drive tractor.
One thing I learned to never do was to wash a running diesel. I once sprayed the injection pump which made it seize and snap the input shaft.
An interesting engine was the International dual fuel engine that we started on gas and switched to diesel. It would not start under any circumstances on diesel so the drill was to start it on gas and pull a big lever when it was warmed up to switch it to diesel. What a setup!
Another one was the Faibanks Morse opposed piston main engine on the Coast Guard ship I was on. We had to pull the crankshaft out while at sea, and then a big storm hit. It was a single rudder ship with twin screws. The seas were so big we couldn't steer without both screws. So we had to.........oh, I'm rambling, back to those sweet little Cummins.

dsljunkie

Cummins engines dont have glow plugs. They have grid and fuel heaters. The "Wait to start" light is pre-heating the grid and the fuel for easier starts. Its a good thing there aint no blasted glow plugs too, I used to have to replace the glow plugs on my 6.9L diesel (Furd) REGULARLY! That is until they got too expensive, then I went with the ol' ether method . Pretty embarrasing when your on a date with a pretty girl and you have to dig out your startin fuel after a movie or somethin : :-.
I LOVE my CUMMINS 8)
Scott

Haulin_in_Dixie

[quote author=Mexstan link=board=8;threadid=21765;start=0#msg203877 date=1067573331]
It was a common practice to remove the air cleaner, twist some newspaper into a long 'stick', light it and hold it over the intake while cranking the engine over. The injectors also had a button incorporated into the shutoff lever that we pushed to supply extra fuel. At least that is what I think it did. [/quote]

Some time ago I put this one in another thread. A couple of years ago I rebuilt a Ford tractor engine on a back hoe, believe it was a 555. I was amazed at the cold start system. You push a button, crank on it and the engine would start. When you pushed the button it pumped raw fuel into the intake housing and a coil heated up to ignite it. In other words raw fuel was lighted and the flames were sucked into the combustion chamber, which ignited the injected fuel. This was not all that old a tractor. They are probably still built that way. Worked better than when I used to drop the hair dryer down the intake stack of the old detroit.

Raspy

The Perkins 4-107 in my boat has that same system. Push a button and hold it for about 30 seconds while it leaks a little fuel into the intake tract and ignites it on a hot wire. Then hit the starter and suck the fire into the engine. Fires right up! Don't you just love common sense technology!
John

Mexstan

This is off topic a little but does concern starting of engines. As a kid I remember a farmer in our area that had a big single cylinder stationary gas engine. The way to start this engine was to place a blank shotgun cartridge in a special hole. Memory fails me but I seem to remember that the big flywheel had to be at a marked start position. Then hit the pin and bang, the engine fired up. Most times. Sometimes he had to do it more then once. Any old timers remember this starting system? If so, maybe you can describe it better than my failed memory.

pappyman

Most of the trucks with bigger diesel engine have a starting aid...its either injection into the air intake for cold starting

Push Rod

[quote author=Wetspirit link=board=8;threadid=21765;start=0#msg203900 date=1067579149]
One of the worst things I saw done to poor diesel engines in the cold was to spray a big amount of starting fluid into them, start them (which resulted a bunch of terrible knocking) and then some guys would spray more in.
[/quote]

Ah yes, fellow ranchers unite. I've got an old 930 Case out here that always wants a breath of ether first thing in the morning to get 'er fired up. On really cold days, she wants a couple more squirts after firing to get 'er going. Kinda like a mornin' cup of coffee. But I have seen others just pour the ether to the tractors. I just cringe everytime I see it.

Rod

98rammer

my best friend's dad has a 97 freightliner FL50 bucket truck with the 5.9. it has no grid heater...will not start without being plugged in for a couple hours if it's under 20* or so. once it does, it pours out white smoke like crazy....plus try getting the truck to move with that cold allison. only a high idle after 15-30 mins will the truck be able to take off.

Tom

bulabula

Someone once told me that real diesels don't have plugs.

dodgeman01

[quote author=Mexstan link=board=8;threadid=21765;start=0#msg203923 date=1067597222]
This is off topic a little but does concern starting of engines. As a kid I remember a farmer in our area that had a big single cylinder stationary gas engine. The way to start this engine was to place a blank shotgun cartridge in a special hole. Memory fails me but I seem to remember that the big flywheel had to be at a marked start position. Then hit the pin and bang, the engine fired up. Most times. Sometimes he had to do it more then once. Any old timers remember this starting system? If so, maybe you can describe it better than my failed memory.
[/quote]
They made a tractor in egland that used this same system. A friend of mine has one and that is how you start it. one time the shell exploded and sent the fireing pin 2" into the hammer he was using to start it
DM01