Engine/Transmission (1998.5 - 2002) Exhaust brake

[ChuckV]

I have a 2001 Dodge with a dealer installed Jacob brake. When I use it to slow down while towing our 5th wheel trailer, it doesn't want to release. Could it be going beyond center or something, or does it just build up enough pressure to keep it closed ? Has anyone else had this trouble, and if so, is there a cure. Thanks for your help.



ChuckV 2001, Extended Cab, 5 speed, stock except for Jake brake and TransFlow tank.

 

[Thomas]

I have never (on the TDR board) read of a problem with the E Brake by Jacobs that involves the vacuum solenoid, vacuum actuator, or a sticking butterfly. I'm assuming that the brake eventually releases. Perhaps a description of what you do to release the brake or what you experience when the brake eventually releases on its own can provide clues.

 

[ChuckV]

If it doesn't release before the light changes I have to just step on the accelerator pedal and it will bog the engine down for several seconds and then finally it will release. People behind me probably think I can't get it going. Thanks, ChuckV

 

[Michael Hughes]

Are you turning the ebrake off while at the light?



I have had my ebrake for 3 years and 157,xxx miles and I have never had any problems with it not opening back up. I do have it on all the time and only turn it off at stop lights and stop signs.

 

[Thomas]

If it doesn't release before the light changes...

It shouldn't release unless you do at least one of the following:

1. Press the throttle

2. Switch the brake off

... I have to just step on the accelerator pedal and it will bog the engine down for several seconds and then finally it will release...

Pushing the pedal is sensed by the ECM and should cut the +12 volt signal to the vacuum solenoid. Switching the brake off does the same thing. In a normally operating brake it takes the vacuum at the actuator to hold the brake closed and the vacuum is only present at the actuator when + 12 volts is present at the vacuum solenoid.



It seems to me that you need to look at the vacuum solenoid and vacuum actuator for signs of sluggish movement and at the linkage from the actuator to the butterfly as well as the butterfly itself. I think any loss of integrity in the vacuum system itself would prevent the butterfly from closing in the first place.

 

[ChuckV]

I switch it off as soon as my speed is down to 15-20 miles per hour, but it will not let go. Some times if I rev the engine to 1100-1200 RPM's while sitting at the light it will release, but not always. Sometimes that just makes the engine bog down worse. Thanks, ChuckV

 

[RWhites]

WE have had trouble with the solinoid control valve. Little spool valve got some water in it and e brake would not release.

Rich

 

[CFast]

you mean these exhaust brakes stay on all the time unless you press the go pedal or hit the switch off? is that just jacobs brakes? That sounds like the old style jake brakes on trucks that would stay on until they killed the engine. New jake brakes on the big trucks kick themselves off at around 1100 rpm whether or not you touch the go pedal. I thougth these exhaust brakes were the same way. Am I wrong? what a pain in the butt to have to switch the damn thing on and off all the time. I'll bet a diesel pusher motor home is wired to shut off at 1100rpm whether or not you hit the pedal.

 

[Supermod56]

Yes, they do stay on, even at an idle, until you barely touch the gas or switch it off. Chuck V, I think you might have a solenoid problem, try hooking vacuum directly from the source to the butterfly valve while the motor is running, that will tell you. I love my Jake Brake!



Tom

 

[CFast]

Is that just the jacob's exhaust brake or do they all do that? I've been looking at the BD brake, doesn't mention whether or not you need to turn it off and on.

 

[mmi]

Mine allways works, so never looked close.

The APPS sensor @ idle enables this circuit to work.

Which should turn on selonid to open letting in vacuum to close butterfly,turning brake on.

when it is stuck pull the vacuum line off, if it shuts off ,its a signal/electrical problem. if not then linkage or possible carbon deposit.

regardless of engine rpm it should only be powered when computer receives,pedal returned to idle signal.

 

[Michael Hughes]

It's not that bad to turn the ebrake off, I made a switch holder that I mounted on the shifter.



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[amsoilman]

Is that just the jacob's exhaust brake or do they all do that? I've been looking at the BD brake, doesn't mention whether or not you need to turn it off and on.

CHUCKV, doesn't your EB have a switch?



This is the "Jacobs" EB switch that came with my unit. It is used to turn the system off. If the switch is pulled up, and the small LED is lit, the system is "on" and waiting for the computer to turn the EB off. This of course is anytime the throttle comes off Idle, or if the clutch is depressed for more than 2 seconds.

I like this feature, as when it is cold outside, I can turn it "on" and the back pressure will help in heating the engine a bit quicker.



Wayne

amsoilman

 

[jerrethomas]

i'm waiting for some adapters to put mine on my truck right now. i plan to add a clutch switch that way i don't have to switch it off at red lights and stop signs. you could add one of those also, you just have to be creative how you mount the micro switch under the dash.

 

[ChuckV]

Thanks, RWhites. I will take a look at that valve as soon as I get back home and can work on it, in a week. Thanks again, ChuckV

 

[ChuckV]

Michael Hughes, Thanks for your input. I made a switch for my shifter a couple years ago, doesn't look as good as yours. I just bought a new one from GENO's that replaces the shift knob and has the switch in the center of the knob. I'll install that at the same time I check out the solenoid valve. Thanks again, ChuckV

 

[ChuckV]

Thanks to all of you who have helped me with this problem. This website is a BIG help. ChuckV