Got A Jake, Can't Make It Brake!!!!!!!!!

[Cummins724]

I HAVE A JACOBS EXHAUST BRAKE, BUT THAT IS ALL I'VE GOT. NO WIRING,NO COMPRESSOR, NOTHING. THE TRUCK IS A 04. 5 6 SPEED. I WAS WONDERING HOW TO MAKE IT WORK? CAN I JUST HOOK UP A COMPRESSOR & A SWITCH? CAN IT BE DONE?

 

[HBarlow]

You have the most expensive and most fundamental part of the exhaust brake "system" but you will have to buy a list of additional parts to install and use it.



First, the Cummins/Jacobs brake works off vacuum not pressure so you need a vacuum pump. Cummins/Jacobs uses and engine driven pump but I suppose you could use an electric pump modified to fit. Second, you need an electrically operated vacuum solenoid switch which routes vacuum to actuate your brake.



I suppose you could use a simple on/off toggle switch to open and close the vacuum solenoid switch but the better and correct way to operate it would be with a proper Cummins/Dodge/Jacobs brake wiring harness that wires the system through your engine's computer. The brake is only supposed to be activated when the engine is at idle rpm or a no fueling condition and only then after an approximate 1 1/2 second to 2 second delay.



Harvey

 

[Cummins724]

Thanks for the feedback, I'll check into it. good to know

 

[ENafziger]

I've got a factory installed jake on my truck, and just had it apart last weekend as a result of a new turbo install. It's just a simple butterfly valve that uses a vacuum pod to engage it. I like your idea of just using a simply electric vacuum pump with a switch. True, the wiring harness supplied with the kit prevents the brake from engaging if the engine is being fueled; however, if you are cautious in this regard, I think it would be beneficial to have the brake come on as soon as you flip a switch, instead of waiting for the 2 second delay. Two seconds can be a long time if you're trying to stop quickly... Either way, you'll be glad you installed it. They're great!