Exhaust brake question for diesel guys....

---you WANT to use the exhaust brake as much as possible. it helps reduce soot on the turbo. IT WILL NOT HURT TO USE IT AT ALL TIMES
 
There is a huge difference between the exhaust brake on the smaller engines and the "Jake Brake" on the large over the road rigs.

If no one explains the differences by the time I return, I will take the time and do it then.
 
Silverback said:
There is a huge difference between the exhaust brake on the smaller engines and the "Jake Brake" on the large over the road rigs.

If no one explains the differences by the time I return, I will take the time and do it then.
Click to expand...
Please enlighten us, oh wise one. Because I don't know a damn thing about them.

Bill.
 
Should have read more,

April 12, 2008
Dear Straight Dope:


Turns out this is a rather hot issue with the company who holds the trade name for Jake brakes, but more on that later. First an introduction to the world of engine brakes.

Unlike the wheel brakes you have on your car, the Jacobs Engine Brake (TM) is a "compression release" engine brake used by large diesel trucks, especially on steep downgrades. To understand how it works, remember that a diesel engine has much higher compression than a gasoline engine, typically 15:1. The jake brake slightly opens the exhaust valves when the piston is near top dead center (where ignition normally occurs). On the upstroke, the piston compresses the air in the cylinder to 1/15th its original volume. This creates a lot of drag on the engine. The Jacobs Engine Brake then releases the compressed air, and the energy stored in it, before it can push back on the piston during the downstroke. In addition, releasing the compression prevents any fuel in the cylinder from igniting. (Remember, diesels don't have spark plugs like gasoline engines - they rely on compression alone to ignite the fuel.) So, you've got drag on the upstroke, no power on the downstroke.

In short, the jake brake turns a power-producing engine into a power-absorbing air compressor, thus slowing the truck. The brake sits in a box over the engine. The trucker has a switch in the cab where she can choose how many cylinders to cut out; the more cylinders, the more powerful the slowing of the truck. This illustration from the Jacobs Engine Brake website may make the whole thing a little clearer.

A bit of history: In 1931, Clessie Cummins, founder of the Cummins Engine Company, drove across the United States to demonstrate off the viability of his new diesel engine. While descending Cajon pass in California (something that took real cajones in those days), the brakes failed on his truck and he and his pals barely survived the hairy ride. After that experience, Cummins devised the idea of an engine brake to supplement the use of wheel brakes on diesel trucks, especially for use on long downgrades.

Cummins developed the compression release engine brake in 1954 and shopped the idea around, but none of the major engine manufacturers were interested. His brother's son introduced him to the Jacobs Manufacturing Company, established in 1903 by A.I. Jacobs, makers of the world famous three jaw Jacobs Drill Chuck. The Jacobs company ran with the idea and marketed a successful line of compression release and other types of brakes. The firm split in 1986 and chuck manufacturing now takes place in Clemson, South Carolina, while engine brake producition remains in Bloomfield, Connecticut under the Jacobs Vehicle Systems name.

All of the brake systems made by Jacobs Vehicle Systems can accurately be called "jake brakes," not just their compression release engine brakes. They also produce the Jacobs Exhaust Brakes and Jacobs Driveline Brakes, both of which are nearly silent. The engine brakes are the ones that make that distinctive staccato sound, and if I could make a WAV, I'd include my imitation of it here.

The Jacobs company blames the loud noise you hear from passing trucks on the use of engine brakes in vehicles with poorly muffled or unmuffled exhaust systems (straight pipes, for example), exhaust systems that have been illegally modified or are poorly maintained, and/or truckers who simply enjoy making noise. Because of this, the Jacobs company feels that it's inaccurate, unfair, and maybe illegal to use their trademarked name in the generic sounding "NO JAKE BRAKES" signs, especially since some of their other jake brakes are quiet and noisy compression release engine brakes are made by other companies, too. These signs are often seen in residential areas adjacent to a highway. The federal government has required all vehicles manufactured since 1978 to meet noise requirements.

The Jacobs brake people go so far as to ask anyone seeing these "brand specific" signs to E-mail the location to them. If you see a "jake brake" sign, send the route number, city/town, and state where you saw it to [email protected].

Now ... who can tell me how to get the grease out from under my fingernails?

— Jill
_________________________________________________________________
http://dodgeram.org/ki4cy/exhbrake/exh_brake.htm
 
http://www.jakebrake.com/products/ld-exhaust.php

AUTOMATIC TRANSMISSION VERSION OF THE JACOBS EXHAUST BRAKE NOW AVAILABLE!
For the 2006 model year, Jacobs is excited to announce the Jacobs Exhaust Brake for Cummins powered automatic transmission-equipped Dodge Rams. The Jake Brake brand exhaust brake, the only OEM-approved brake for the Cummins-powered Dodge Ram, is available at Dodge dealers and Cummins Distributors in the US and Canada. The Mopar part number for the 2006 exhaust brake (automatic and manual) is 82209823 and the Cummins part number is 4955192. The new exhaust brake utilizes updated powertrain software to maximize torque converter lock-up performance and to protect the Ram's 48RE four speed automatic transmission.( BTW, Could this have anything to do with the flex plate problems you have been having???)This results in up to 170 retarding horsepower to provide enhanced vehicle control and increased service brake life.

Why would I need an exhaust brake for my Cummins-powered Dodge Ram?

Unlike gasoline engines, diesel engines produce no vacuum when you release the throttle to help slow the vehicle. The higher compression of the diesel acts like a spring on the crankshaft, even with no fueling. An exhaust brake restricts the exhaust, making the pistons work harder, slowing the crankshaft and the truck.

Exhaust brakes are ideal for towing applications, such as pulling RV fifth wheels and horse trailers. The Jacobs Exhaust Brake is especially popular with Ram owners who drive in hilly and mountainous regions for the added control on steep grades.

You stepped up to the Cummins Turbo Diesel for its legendary torque and performance. Now upgrade to its ideal heavy-duty partner, the legendary Jake Brake brand, Jacobs Exhaust Brake, for added control and brake savings as well!


HOW IT WORKS
The Jacobs Exhaust Brake® is a supplementary braking system used to help slow your vehicle. This slowing power is achieved by restricting the flow of exhaust gases and increasing back pressure inside the engine. This increased back pressure creates resistance against the pistons in your engine, slowing the crankshaft's rotation and ultimately helping to slow your vehicle.
 
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Jerry already hit on one thing, in some areas it is illegal to use engine brakes due to the noise, though I doubt you'll get stopped for it in an ambulance. But then again there are some real dickhead cops out there, so who knows?
 
OCBob said:
Jerry already hit on one thing, in some areas it is illegal to use engine brakes due to the noise, though I doubt you'll get stopped for it in an ambulance. But then again there are some real dickhead cops out there, so who knows?
Click to expand...

Yes they can be noisy, used to love driving the KW(with strait pipes) thru town using the Jake at every chance. Broke a couple of windows though:D
And you are right , the Smokey's just love to write ya up:(
 
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those drive line brakes are badass.
 
Thanks for filling in for me Jerry. :rock:

The one thing that was eluded to, but missing is that "true" diesel engines do not have throttle plates in the intake system. That is why there is not vacuum in the intake system at any time.

Without those throttle plates, the engine is sucking in the all the air it can. Hence, no vacuum to help slow you down as in a gas engine.

Thanks again Jerry.:rock: :rock:
 
Well Dad, between your fur and mine...........well remember the last time we hugged............took a week to get untangled :eek::D ;)
 
includemeout said:
Well Dad, between your fur and mine...........well remember the last time we hugged............took a week to get untangled :eek::D ;)
Click to expand...
I was there, I remember that.:D

Bill.
 
OCBob said:
Jerry already hit on one thing, in some areas it is illegal to use engine brakes due to the noise, though I doubt you'll get stopped for it in an ambulance. But then again there are some real dickhead cops out there, so who knows?
Click to expand...

An exhaust brake does not make noise like a jake brake on a large truck. It sounds like a stopped up exhaust, because that is what it does, closes off the exhaust.
 
the mercedes engines have a exhaust break and a engine break. nuthin like the old jake brakes. we ran them on our last fleet of trucks. davids right it sounds like a souped up hair dryer
 
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