[VAC] Re: Exhaust brakes - A word of caution

[Harvey Barlow]

Tom,   I am familiar with the reasons why diesel engines naturally produce limited compression braking compared to gas engines as well as how and why exhaust brakes are used.  But I had the understanding that an exhaust brake was only activated on demand by the driver.   What I was not aware of is the idea that the exhaust brake is either switched on or switched off and is activated every time you lift your foot from the throttle pedal.  I don't think I would like that method of operation.  Are all brands of aftermarket exhaust brakes activated in the same manner?   I know that Jacobs, the original "Jake Brake" which has been used on 18 wheelers for 30 years or more is authorized by Cummins, the engine manufacturer for sale and installation on Cummins engines including Cummins powered Dodge Rams by either Cummins shops or Dodge dealers.  I checked and found that a local Dodge dealer can sell it through MOPAR parts and install it in their service department.   Has anyone out there had any experience with a Jacobs "Jake Brake"?   Harvey ----- Original Message ----- From: Tom Patterson To: Multiple recipients of VACList Sent: Sunday, June 10, 2001 8:40 AM Subject: [VAC] Re: Exhaust brakes - A word of caution Harvey,        The exhaust brake is turned on or off by the driver by means of a switch.  When the brake is on however, it is not activated until you take your foot off of the gas pedal.  At that time, the engine exhaust is blocked, which causes the engine to act as a brake.  This works well when descending hills, or in heavy traffic, when you might prefer your truck and rig to slow down when you take your foot off of the gas pedal.  It did not work well when I took my foot off so as to roll through the standing water.      When the exhaust brake is not turned on, the diesel engine tends to freewheel, rather than retard the vehicle as does a gasoline engine.   -Tom   ----- Original Message ----- From: Harvey Barlow To: Multiple recipients of VACList Sent: Sunday, June 10, 2001 8:11 AM Subject: [VAC] Re: Exhaust brakes - A word of caution Tom,   I am not familiar with BD exhaust brakes but plan to install an exhaust brake when I purchase a new diesel puller in the near future.  Reading your post I am confused by the comment, "I was travelling with the brakes on" then goes on to describe your near disaster experience.   The way you described the event seems to say that application of the BD exhaust brake was not a direct result of driver action.   Is the BD exhaust brake applied other than on demand by the driver?   Harvey