What part of the truck doesn't burn?

Why doesn’t John deere make you cover their stacks when you load in Waterloo even if you’re going all the way to California I guess they like replacing those brand new turbos believe me if it damaged anything John Deere would make you take care of it !I’ve been hauling out of there for almost 30 years so yes I’m just wondering ?

 

years ago when I was debating this with an equipment owner, I was searching the internet for any evidence that plugging the exhaust was required. I found a site where a guy contacted all the north American diesel engine manufacturers via mail asking about it, and had letters from engineers on the company letterhead paper that stated the turbo would not spin due to air passing over, or forced into the exhaust pipe. the only manufacturer that told him it was a good idea to plug the exhaust was Detroit Diesel. and only because the engineer wasn't certain for sure, and said better to be safe than sorry. I sure wish I had saved those letters when I found them.

 

If you choose to replace the well established science of suction draw with anecdotal hearsay you would be in the majority in the trucking industry, apply whatever standard you like to your practices

 

suction draw requires both ends to be open and unrestricted to allow airflow. this cannot happen in a modern turbocharged diesel engine.

 

So "modern turbocharged diesel engines" have all of the intake valves closed at the same time whenever the engine shuts off?

I would be very interested in hearing which engine manufacture managed that impossible feat and more importantly why they thought that was a good idea?

That was sarcasm by the way, no such internal combustion engine has ever, will ever or can ever be designed that way and there would be no reason to ever even consider such a ridiculous notion.

 

is it your assertion that both intake and exhaust valves are wide open on the same cylinder when an engine shuts off? because that would be a ridiculous notion, and the only way air could pass thru the engine to spin the turbo.

 

The intake valve begins to open at the crown of the exhaust stroke, and on EGR engines (which is basically all of them now) the EGR assembly is a direct path from exhaust manifold to the intake manifold; with no pressure being created by turbo there are always several paths to air through the exhaust.

There is no such thing as an internal combustion engine that can hold vacuum applied at the stacks.

 

what opens the EGR valves when the engine is shut off?

 

EGR valves don't seal, they are regulated but they cannot be sealed off unless you physically weld blocking plates into the plumbing; when they are "closed" they rely on more boost pressure on the intake side than pressure on the exhaust side to reduce the flow of exhaust to "near zero" but nothing in the exhaust system can close to a seal.

 

No heat. No load. No RPM. No damage. Not a real thing.

If this was a real thing, manufacturers would equip every turbocharged engine with an accumulator (cylinder that pressurizes with oil while running and then discharges and supplies oil after engine shutdown). Under normal operation, turbos spin upwards of 200,000 RPM (give or take). ONE engine shutdown will result in more residual RPMs without pressurized oil than will result from an uncovered exhaust being hauled coast-to-coast for 40 years (even if the turbo would spin... which it won't).

There are other, legitimate, reasons to cover the exhaust and the one that tops the list is because the paying customer requests it. I don't care what their reason is so long as it doesn't jeopardize my employees, my equipment or my business.