quote:

Originally posted by Schmelby:
[QUOTE]Originally posted by petr:
At a flat idle? No way! Never flat idle a diesel engine for extended periods of time

Have you ever been in a truck stop at night? If it's hot or cold there are a 150
trucks idling their engines for ten straight hours.

Yes I have and to expand on that, my Dad has been a truck driver for 44 years. Idling a diesel has always been an issue but most drivers do not learn about it or care about it. Drive it like you stole it mentality. Most states now have a no idling law. Companies install A.P.U.'s on their tractors in order to provide heat/A.C. in the cabs while they lay over or are loading or unloading. The majority of the drivers in the past have not let their engines flat idle for extended periods of time and "idled" them up. I installed the idle control unit from Ford on my Super Duty while I had it. Most ambulances have the same unit installed on them also. Many other manufacturers, Freightliner included, use the cruise control to idle up the engines.

Speaking strictly of the big semi-truck tractor engines, many years ago when I was a driver manager we were to advise drivers to let the engine warm up until the temp gauge stared moving up.

The theory, or fact, or bullshit rumor, or whatever, was that the Head Bolts would stretch if you drove off right away, before they had a chance to warm up and be able to handle the compression forces (mighty considerable on a big diesel).

I'm not saying if this was right or not, but it was conventional wisdom and advice and thus best practice back in the day.
.

quote:

Originally posted by petr:

quote:

Originally posted by Schmelby:
[QUOTE]Originally posted by petr:
At a flat idle? No way! Never flat idle a diesel engine for extended periods of time

Have you ever been in a truck stop at night? If it's hot or cold there are a 150
trucks idling their engines for ten straight hours.

Yes I have and to expand on that, my Dad has been a truck driver for 44 years. Idling a diesel has always been an issue but most drivers do not learn about it or care about it. Drive it like you stole it mentality. Most states now have a no idling law. Companies install A.P.U.'s on their tractors in order to provide heat/A.C. in the cabs while they lay over or are loading or unloading. The majority of the drivers in the past have not let their engines flat idle for extended periods of time and "idled" them up. I installed the idle control unit from Ford on my Super Duty while I had it. Most ambulances have the same unit installed on them also. Many other manufacturers, Freightliner included, use the cruise control to idle up the engines.

I drove for 42 years. In my observation, there are still not a lot of trucks with APU's . My company knew exactly how many minutes
my truck idled. The average diesel burns a half gallon of fuel in 30 minutes. If it's 90 degrees and I'm not worth a half gallon of fuel to eat my lunch in comfort, they can bite me. One more reason I retired. Sorry for the thread drift.
in

Ah, the bigone days of cold starting a Mercedes 190Dc 4 cylinder Diesel with glow plugs.

Just pull that big knob and watch that big light glow red while you shiver on the cold leather seat.

Most Diesel powered cars/trucks now have a heated fuel line plus manifold heater to aid starting in cold weather.

For some reason, practices from decades ago for mechanical diesels (and carbureted gas engine with no electronics but the distributor) live on well past any relevance.

Start it, drive it, but don't drive it too hard until it hits operating temperature.

Its an odd thing to me. But I have big investments in CAT off road equipment. The book says warm up, and then cool down before shutting down. So I do exactly that 5+ to start (temp dependent) 2 to shut down. My onroad pickup has only cool down when hammering in the book so I do that. Now when I'm max towing the dynamics of hitching up or even checking means a couple of minutes of warmup time.
But going for beer. Start and go. I don't hammer on it right away but that's true for any engine I own.
NET NET makes not a hoot of difference.

quote:

Originally posted by hrcjon:
Its an odd thing to me. But I have big investments in CAT off road equipment. The book says warm up, and then cool down before shutting down. So I do exactly that 5+ to start (temp dependent) 2 to shut down. My onroad pickup has only cool down when hammering in the book so I do that. Now when I'm max towing the dynamics of hitching up or even checking means a couple of minutes of warmup time.
But going for beer. Start and go. I don't hammer on it right away but that's true for any engine I own.
NET NET makes not a hoot of difference.

I was taught when you got back to the plant, let your truck idle for a few minutes to cool down.
Then the plant manager would yell at me for my truck idling. ok, fine not my money.

Actually she is doing NO HARM. With diesels it is good to let them idle and warm up to let the oil thin a bit and internal components to warm up. In a vehicle, although 7 minutes is a bit long. I manage many different yachts, most engines are $250-500k each, the owners manual instructs you to warm them up before leaving the dock. It's SOP to let the engines idle 20-30 minutes before even leaving the dock in our industry. A little different than a vehicle because they are either in or out of gear and only geared/propped for top end rpm, so when you put them in gear you see 50-60% load factors until the many tons of boat get moving. Diesels don't like to idle for hours on end, but 7 minutes certainly isn't going to hurt them.

Re diesel idling: I worked in Spain, 1977 & 1978. Ordered a new MB 240D diesel, picked it up at the factory, and brought it home with me. Never had a cold weather problem until I was assigned to a project at Bell Labs just north of Denver. The altitude and the cold winter days conspired to keep it from starting at the end of the work day.

The employee parking lot had light poles, obviously with electric power, but the company refused to put outlets on the light poles that would have served the engine heater that I had on the car.

I called the MB-U.S.A. mother ship and spoke with a tech rep, asking whether prolonged idle would be harmful. He told me that would not be a problem. The 4-cylinder non-turbo engine would use less than a cup of fuel idling for an hour, and he told me that many of these that are sold in Alaska, or Northern Europe, are never shut down for months of winter except when they're in the shop for oil changes.

So, when temps were below 20° F, I left the car idling in the employee parking lot all day. Every once in a while I would get a call from the security guards, informing me that my car was running. "Good, thank you," was my reply.

Two winters like this, and when I sold the car ten years later, with around half million miles on it, the engine was in fine shape.

A diesel engine on it's own could idle indefinitely with little wear.
The after treatment system does not like extended idle time however.

quote:

Originally posted by powermad:

A diesel engine on it's own could idle indefinitely with little wear. The after treatment system does not like extended idle time however.

Ah, I see. I'm not 100% sure, but I don't think that the 1978 MB diesel automobiles had any after treatment system, and that's the last diesel that I had any experience with.

quote:

Originally posted by bendable:
Betsy purchased a brand spanking new dodge 3/4 ton 4x4 to pull her 5th wheel, five years ago .

Her son has been a mechanic for Caterpillar for 16 years.

Since year one, she has waited 7 minutes after start up before putting the trans. In go.

Do most diesel drivers do this ? From a cold start.

I start up, idle about 10-30 seconds, and drive off very easy. Don't jump on the "throttle" until it's up to operating temp.

no,

turn key, wait for engine light to go off (maybe 10 seconds?) and start up

the trans at 100K is a bit cold natured now, so it will 'hang' in gear until it warms up a bit, which is usually about 2 miles down the road,

hangs as in a delay in shifting,

2005 Foad E350

quote:

Originally posted by V-Tail:

quote:

Originally posted by powermad:

A diesel engine on it's own could idle indefinitely with little wear. The after treatment system does not like extended idle time however.

Ah, I see. I'm not 100% sure, but I don't think that the 1978 MB diesel automobiles had any after treatment system, and that's the last diesel that I had any experience with.

No they didn't. Aftertreatment his the US in 2007. Europe was a similar time frame, although they went a different route. At the time US went with EGR + DOC/DPF. Europe went straight to SCR without the other stuff.

Speaking of the aftertreatment system.
Here was my project for today, replacing the SCR in a bus.



To get the DPF out you take all the brackets off and drag it out through the top also.


$4,800 for the SCR, the DOC and DPF assy is about another $5,000.