Exhaust Brake
Senior User
Joined: Feb 2003
Posts: 420
Likes: 0
From: Ohio
Not sure whether it's even available in an SD, ..... BUT
an engine brake typically works like this: (otherwise known as a jacobs engine brake...."jake break")
The cam shaft(s) is/are "double lobed" cams.... TWO lobes for each valve, with one set of lobes engaged at any given time.
When you "engage" the engine break, the cam shaft(s) shift/slide axially, thus engaging the second set of lobes, thus changing the valve timing.
The valve timing is changed in such a way as to turn the diesel from a power PRODUCING engine to a power CONSUMING air compressor....
Thus the raspy sound when it's engaged...thus the "breaking" that occurs because the forward momentum of the vehicle is being absorbed by the engine/drive train to compress air. The diesel engine/vehicle becomes a huge reciprocating compressor, discharging its compressed air through the exhaust.
As this installation (after the fact) would involve SERIOUS valve train work...I would assume that an aftermarket addition of a true engine brake wouldn't be economical. DO they offer the diesel with a jake brake as an option.... NO CLUE.
Hope this helps.
an engine brake typically works like this: (otherwise known as a jacobs engine brake...."jake break")
The cam shaft(s) is/are "double lobed" cams.... TWO lobes for each valve, with one set of lobes engaged at any given time.
When you "engage" the engine break, the cam shaft(s) shift/slide axially, thus engaging the second set of lobes, thus changing the valve timing.
The valve timing is changed in such a way as to turn the diesel from a power PRODUCING engine to a power CONSUMING air compressor....
Thus the raspy sound when it's engaged...thus the "breaking" that occurs because the forward momentum of the vehicle is being absorbed by the engine/drive train to compress air. The diesel engine/vehicle becomes a huge reciprocating compressor, discharging its compressed air through the exhaust.
As this installation (after the fact) would involve SERIOUS valve train work...I would assume that an aftermarket addition of a true engine brake wouldn't be economical. DO they offer the diesel with a jake brake as an option.... NO CLUE.
Hope this helps.
Post Fiend
Joined: Apr 2002
Posts: 5,438
Likes: 11
From: IN FRONT OF YOU
Last edited by Yeti; Jan 28, 2004 at 07:59 PM.
